1

     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON JUNE 29, 2001.
                                                      REGISTRATION NO. 333-59094


================================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
--------------------------------------------------------------------------------


                               AMENDMENT NO. 1 TO
                                    FORM S-4
                             REGISTRATION STATEMENT
                                      UNDER
                           THE SECURITIES ACT OF 1933


                                   ---------

                        PIONEER NATURAL RESOURCES COMPANY
             (Exact Name of Registrant as Specified in its Charter)


                                                                     
        DELAWARE                                  1311                         75-2702753
(State or Other Jurisdiction of       (Primary standard industrial          (I.R.S. Employer
Incorporation or Organization)         classification code number)         Identification No.)


                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 77039
                                 (972) 444-9001
               (Address, including zip code, and telephone number,
        including area code, of registrant's principal executive offices)

                                   ---------

                               SCOTT D. SHEFFIELD
                        PIONEER NATURAL RESOURCES COMPANY
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 77039
                                 (972) 444-9001
                (Name, address, including zip code, and telephone
               number, including area code, of agent for service)

                                   ---------

                                   COPIES TO:

     ROBERT L. KIMBALL                                  BRIAN M. LIDJI
  VINSON & Elkins L.L.P.                            Sayles, Lidji & Werbner
 3700 Trammell Crow Center                        A Professional Corporation
     2001 Ross Avenue                               4400 Renaissance Tower
    Dallas, Texas 75201                                 1201 Elm Street
      (214) 220-7700                                  Dallas, Texas 75270
                                                        (214) 939-8700

     Approximate date of commencement of proposed sale to the public: As soon as
practicable after the effective date of this registration statement which
relates to the merger of limited partnerships with and into Pioneer Natural
Resources USA, Inc. pursuant to the merger agreement described in the enclosed
proxy statement/prospectus.

                                   ---------

     If the securities being registered on this form are being offered in
connection with the formation of a holding company and there is compliance with
General Instruction G, check the following box. [ ]

     If this form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, check the following box and
list the Securities Act registration statement number of the earlier effective
registration statement for the same offering. [ ]

     If this form is a post-effective amendment filed pursuant to Rule 462(d)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [ ]

                         CALCULATION OF REGISTRATION FEE



============================================================================================================
                                                   PROPOSED MAXIMUM       PROPOSED MAXIMUM        AMOUNT OF
   TITLE OF EACH CLASS OF        AMOUNT TO BE         OFFERING               AGGREGATE          REGISTRATION
SECURITIES TO BE REGISTERED     REGISTERED(1)      PRICE PER SHARE(2)     OFFERING PRICE(2)        FEE (2)
------------------------------------------------------------------------------------------------------------
                                                                                     
Common Stock, $0.01 par value     6,587,764               $8.55               $56,300,000          $14,075
============================================================================================================



     (1) Based upon the registrant's estimate of the maximum number of shares
that might be issued in connection with the proposed merger transaction.


     (2) Estimated solely for the purpose of calculating the registration fee
pursuant to Rule 457(f), based on the book value of the unaffiliated partnership
interests to be cancelled in the transaction, computed as of the latest
practicable date. A filing fee of $20,500 was paid pursuant to the filing on
April 17, 2001 by the registrant and Pioneer Natural Resources USA, Inc. of a
preliminary Schedule 13e-3. Pursuant to Rule 240.0-11(a)(2) of the Securities
Exchange Act of 1934, this amount has been credited against the amount that
would otherwise be payable in connection with this filing, resulting in no
additional payment herewith.


     THE REGISTRANT HEREBY AMENDS THIS REGISTRATION STATEMENT ON SUCH DATE OR
DATES AS MAY BE NECESSARY TO DELAY ITS EFFECTIVE DATE UNTIL THE REGISTRANT SHALL
FILE A FURTHER AMENDMENT WHICH SPECIFICALLY STATES THAT THIS REGISTRATION
STATEMENT SHALL THEREAFTER BECOME EFFECTIVE IN ACCORDANCE WITH SECTION 8(a) OF
THE SECURITIES ACT OF 1933 OR UNTIL THE REGISTRATION STATEMENT SHALL BECOME
EFFECTIVE ON SUCH DATE AS THE SECURITIES AND EXCHANGE COMMISSION, ACTING
PURSUANT TO SAID SECTION 8(a), MAY DETERMINE.

================================================================================

   2


                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 Williams Square West
                            5205 North O'Connor Blvd.
                               Irving, Texas 75039

                 NOTICE OF SPECIAL MEETINGS OF LIMITED PARTNERS
                          TO BE HELD ON       , 2001

To the Limited Partners of 46
Parker & Parsley Limited Partnerships:

     This is a notice that a special meeting of the limited partners of each of
the following 46 limited partnerships will be held on             , 2001, at
10:00 a.m., at the Dallas Marriott Las Colinas Hotel, Irving, Texas 75039:


                                                      
Parker & Parsley 81-I, Ltd.                              Parker & Parsley 88-A Conv., L.P.
Parker & Parsley 81-II, Ltd.                             Parker & Parsley 88-A, L.P.
Parker & Parsley 82-I, Ltd.                              Parker & Parsley 88-B Conv., L.P.
Parker & Parsley 82-II, Ltd.                             Parker & Parsley 88-B, L.P.
Parker & Parsley 82-III, Ltd.                            Parker & Parsley 88-C Conv., L.P.
Parker & Parsley 83-A, Ltd.                              Parker & Parsley 88-C, L.P.
Parker & Parsley 83-B, Ltd.                              Parker & Parsley Producing Properties 88-A, L.P.
Parker & Parsley 84-A, Ltd.                              Parker & Parsley Private Investment 88, L.P.
Parker & Parsley 85-A, Ltd.                              Parker & Parsley 89-A Conv., L.P.
Parker & Parsley 85-B, Ltd.                              Parker & Parsley 89-A, L.P.
Parker & Parsley Private Investment 85-A, Ltd.           Parker & Parsley 89-B Conv., L.P.
Parker & Parsley Selected 85 Private Investment, Ltd.    Parker & Parsley 89-B, L.P.
Parker & Parsley 86-A, Ltd.                              Parker & Parsley Private Investment 89, L.P.
Parker & Parsley 86-B, Ltd.                              Parker & Parsley 90-A Conv., L.P.
Parker & Parsley 86-C, Ltd.                              Parker & Parsley 90-A, L.P.
Parker & Parsley Private Investment 86, Ltd.             Parker & Parsley 90-B Conv., L.P.
Parker & Parsley 87-A Conv., Ltd.                        Parker & Parsley 90-B, L.P.
Parker & Parsley 87-A , Ltd.                             Parker & Parsley 90-C Conv., L.P.
Parker & Parsley 87-B Conv., Ltd.                        Parker & Parsley 90-C, L.P.
Parker & Parsley 87-B, Ltd.                              Parker & Parsley Private Investment 90, L.P.
Parker & Parsley Producing Properties 87-A, Ltd.         Parker & Parsley 90 Spraberry Private Development, L.P.
Parker & Parsley Producing Properties 87-B, Ltd.         Parker & Parsley 91-A, L.P.
Parker & Parsley Private Investment 87, Ltd.             Parker & Parsley 91-B, L.P.



     Parker & Parsley Petroleum USA, Inc. and other predecessors of Pioneer
Natural Resources USA, Inc., a Delaware corporation that we call Pioneer USA,
sponsored each of the partnerships. Pioneer USA is the managing or sole general
partner of each of the partnerships. Pioneer USA is a direct 100% owned
subsidiary of Pioneer Natural Resources Company, a Delaware corporation that we
call Pioneer Parent.


     The purpose of the special meeting for each partnership in which you own an
interest is for you to consider and vote on the following matters:


     1. A proposal to approve an Agreement and Plan of Merger dated as of ,
2001, among Pioneer Parent, Pioneer USA and each of the partnerships. Each
partnership that approves this proposal, which we call a participating
partnership, will merge with and into Pioneer USA, with Pioneer USA surviving
the merger. Each partnership interest of a participating partnership, other than
Pioneer USA's partnership interests, will be converted into shares of common
stock, par value $.01 per share, of Pioneer Parent. The number of shares of
common stock Pioneer Parent will offer for all partnership interests of a
participating partnership will be based on (1) the participating partnership's
merger value and (2) the average closing price of the Pioneer Parent common
stock, as reported by the New York Stock Exchange, for the ten trading days
ending three business days before the initial date of the special meeting for
the partnership. The merger value for a participating partnership is equal to
the sum of the present value of estimated future net revenues from the
partnership's estimated oil and gas reserves and its net working capital, in
each case as of March 31, 2001, less its pro rata share, based on its reserve
value, of the estimated expenses and fees of the mergers of all of the
partnerships and less the cash distribution to be mailed on or about July 12,
2001, by the partnership to its partners. For purposes of illustration in this
document, we have calculated the number of shares to be issued based on an
assumed average closing price of $18.00 per share of Pioneer Parent common
stock. Prior to the date of the special meeting for each partnership, we will
update the number of shares to be issued using the actual average closing price
of Pioneer Parent common stock for the ten trading days ending three business
days before the initial date of the special meeting. The Pioneer Parent common
stock will be allocated among the partners based on the liquidation provisions
of each partnership agreement. Pioneer Parent will not issue fractional shares
to any limited partner upon completion of the merger of any partnership.
Instead, Pioneer Parent will round any fractional shares of Pioneer Parent
common stock up to the nearest whole share. Pioneer USA will not receive any
Pioneer Parent common stock for its partnership interests in the participating
partnerships.



                                      -1-
   3


     2. A proposal to amend the partnership agreement of each partnership to
permit the partnership's merger with Pioneer USA. If the amendment is not
approved, that partnership cannot merge into Pioneer USA even if the partners of
that partnership approve the merger agreement.

     3.  A proposal (A) to approve the opinion issued to Pioneer USA by
on behalf of the limited partners of each partnership that neither the grant nor
the exercise of the right to approve the merger of the partnership by its
limited partners (1) will result in the loss of any limited partner's limited
liability or (2) will adversely affect the federal income tax classification of
the partnership or any of its limited partners and (B) to approve the selection
of as special legal counsel for the limited partners of each partnership to
render the legal opinion.


     4. Other business that properly comes before the special meeting or any
adjournments or postponements of the special meeting. Pioneer USA is not aware
of any other business for the special meeting.



     The accompanying proxy statement/prospectus contains information about each
merger, including the amount of Pioneer Parent common stock that will be offered
to limited partners per $1,000 initial investment in each partnership, and
descriptions of the merger agreement, the merger amendment and the legal opinion
of the special legal counsel for the limited partners. The proxy
statement/prospectus also contains a copy of the merger agreement, the merger
amendment and the legal opinion.


     Pioneer USA set the close of business on              , 2001, as the record
date to identify the limited partners who are entitled to notice of and to vote
at each special meeting or any adjournments or postponements of the special
meeting. During the ten business days before the special meeting, you may
examine lists of the limited partners of each partnership in which you own an
interest at the offices of Pioneer USA during normal business hours for any
purpose relevant to the special meeting for each partnership in which you own an
interest.


     ON             , 2001, PIONEER USA'S BOARD OF DIRECTORS UNANIMOUSLY
DETERMINED THAT THE MERGER OF EACH PARTNERSHIP IN WHICH YOU OWN AN INTEREST IS
ADVISABLE, FAIR TO YOU AS AN UNAFFILIATED LIMITED PARTNER, AND IN YOUR BEST
INTERESTS. THE BOARD RECOMMENDS THAT YOU, AS AN UNAFFILIATED LIMITED PARTNER,
VOTE FOR THE MERGER AGREEMENT, THE MERGER AMENDMENT, THE SELECTION OF SPECIAL
LEGAL COUNSEL FOR THE LIMITED PARTNERS AND THAT COUNSEL'S LEGAL OPINION FOR EACH
PARTNERSHIP IN WHICH YOU OWN AN INTEREST. ALTHOUGH PIONEER USA'S BOARD OF
DIRECTORS HAS ATTEMPTED TO FULFILL ITS FIDUCIARY DUTIES TO YOU, PIONEER USA'S
BOARD OF DIRECTORS HAD CONFLICTING INTERESTS IN EVALUATING EACH MERGER BECAUSE
EACH MEMBER OF ITS BOARD OF DIRECTORS IS ALSO AN OFFICER OF PIONEER PARENT. Each
partnership requires a favorable vote of the holders of a majority of its
limited partnership interests to approve the merger agreement, the merger
amendment, the selection of special legal counsel for the limited partners and
that counsel's legal opinion, except that Parker & Parsley 91-A, L.P. and Parker
& Parsley 91-B, L.P. each require the favorable vote of the holders, other than
Pioneer USA, of 6-2/3% of its limited partnership interests to approve those
merger proposals.


     IF YOU DO NOT SEND IN YOUR PROXY CARD OR VOTE AT THE SPECIAL MEETING FOR A
PARTNERSHIP IN WHICH YOU OWN AN INTEREST, IT WILL HAVE THE SAME EFFECT AS IF YOU
VOTED AGAINST THE MERGER OF THAT PARTNERSHIP.

     You are requested to sign, vote and date the enclosed proxy card and return
it promptly in the enclosed envelope, even if you expect to be present at each
special meeting for the partnerships in which you own an interest. If you give a
proxy, you can revoke it at any time before the special meeting for the
partnership as to which you are revoking your proxy. If you are present at the
special meeting for a partnership in which you own an interest, you may withdraw
your proxy and vote in person.

                                            By Order of the Board of Directors,

                        , 2001
                                            Mark L. Withrow
                                            Director, Executive Vice President,
                                            General Counsel and Secretary



                                      -2-
   4


The information in this prospectus is not complete and may be changed. We may
not sell these securities until the registration statement filed with the
Securities and Exchange Commission is effective. This prospectus is not an offer
to sell these securities and it is not soliciting an offer to buy these
securities in any state where the offer or sale is not permitted.


PRELIMINARY PROXY STATEMENT/PROSPECTUS, SUBJECT TO COMPLETION, DATED
JUNE    , 2001                                                            [LOGO]

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                                                                          , 2001
Dear Limited Partners:



     Pioneer Natural Resources Company, a Delaware corporation that we call
Pioneer Parent, and we at Pioneer Natural Resources USA, Inc., a Delaware
corporation and 100% owned subsidiary of Pioneer Parent that we call Pioneer
USA, desire to acquire 46 limited partnerships. We are the managing or sole
general partner of each of the partnerships.



     If you and the other limited partners of a partnership approve the merger
of the partnership, the partnership will be merged with and into Pioneer USA,
with Pioneer USA surviving the merger. We call each partnership that merges into
Pioneer USA a participating partnership. Each partnership interest of a
participating partnership will be converted into shares of common stock, par
value $.01 per share, of Pioneer Parent. The number of shares of common stock
Pioneer Parent will offer for all partnership interests of a participating
partnership will be based on (1) the participating partnership's merger value
and (2) the average closing price of the Pioneer Parent common stock, as
reported by the New York Stock Exchange, for the ten trading days ending three
business days before the initial date of the special meeting for the
partnership. The merger value for a participating partnership is equal to the
sum of the present value of estimated future net revenues from the partnership's
estimated oil and gas reserves and its net working capital, in each case as of
March 31, 2001, less its pro rata share, based on its reserve value, of the
estimated expenses and fees of the mergers of all of the partnerships and less
the cash distribution to be mailed on or about July 12, 2001, by the partnership
to its partners.



     The merger value for each partnership is based on the reserve value of the
partnership's underlying properties, which reserve value has not been reduced
for general and administrative expenses. As a result, we believe the merger
value is essentially the same value or a higher value than the liquidation value
that might have been achieved by selling the partnership's property interests on
March 31, 2001, and liquidating the partnership at that time.



     We have retained Robert A. Stanger & Co., Inc., which we call Stanger, to
issue an opinion regarding the fairness of the merger value to the limited
partners in connection with the merger of each partnership. The written opinion
of Stanger is contained in this document. You should read all of it carefully.



     We can complete the merger of each partnership only if the holders of its
limited partnership interests approve the merger agreement, the amendment to the
partnership agreement to permit the merger, the selection of special legal
counsel for the limited partners and that counsel's legal opinion. This document
provides information about each proposed merger. This document also constitutes
a prospectus by Pioneer Parent for up to an aggregate of 5,855,813 shares of
Pioneer Parent common stock to be issued in the proposed merger transaction,
based on an assumed average closing price of $18.00 per share of Pioneer Parent
common stock. Please give all of this information your careful attention.


     YOUR VOTE IS IMPORTANT. Whether or not you plan to attend the special
meeting for each partnership in which you own an interest, please take the time
to vote by completing and mailing to us the enclosed proxy card. This will not
prevent you from revoking your proxy at any time prior to the special meeting
for each partnership in which you own an interest or from voting your
partnership interests in person if you later choose to attend the special
meeting for each partnership in which you own an interest.


     We intend to mail certificates representing shares of Pioneer Parent common
stock to the partners of each partnership that approves the merger transaction
promptly after completing the merger of the partnership. Certificates
representing partnership interests will be automatically cancelled, and you will
not have to surrender your certificates to receive the Pioneer Parent common
stock.



     YOUR CERTIFICATE THAT YOU ARE NOT A FOREIGN PERSON, WHICH WE CALL A
CERTIFICATION OF NON-FOREIGN STATUS, IS IMPORTANT. Whether or not you plan to
vote on the merger of each partnership in which you own an interest, please take
the time to complete and return to us the enclosed certification of non-foreign
status. If we receive a properly completed certification of non-foreign status
from you, we will not withhold federal income taxes on the Pioneer Parent common
stock to be issued to you upon the merger of each partnership in which you own
an interest.


                                             Sincerely,


                                             Mark L. Withrow
                                             Director, Executive Vice President,
                                             General Counsel and Secretary

     YOU SHOULD CAREFULLY CONSIDER THE RISKS RELATING TO THE MERGER OF EACH
PARTNERSHIP IN WHICH YOU OWN AN INTEREST DESCRIBED IN "RISK FACTORS" BEGINNING
ON PAGE 17. THESE INCLUDE:


     o    THE MERGER VALUE FOR THE PARTNERSHIP DETERMINES THE AMOUNT OF PIONEER
          PARENT COMMON STOCK YOU WILL RECEIVE IN THE MERGER OF THE PARTNERSHIP.
          PIONEER PARENT AND PIONEER USA DETERMINED EACH MERGER VALUE AND WILL
          NOT ADJUST IT FOR CHANGES IN PARTNERSHIP VALUE BEFORE THE MERGER IS
          COMPLETED.


     o    YOU WERE NOT INDEPENDENTLY REPRESENTED IN ESTABLISHING THE TERMS OF
          ANY MERGER.


     o    OUR BOARD OF DIRECTORS HAD CONFLICTING INTERESTS IN EVALUATING EACH
          MERGER BECAUSE EACH MEMBER OF OUR BOARD OF DIRECTORS IS ALSO AN
          OFFICER OF PIONEER PARENT.



     NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
REGULATORS HAVE APPROVED ANY OF THE MERGERS, THE PIONEER PARENT COMMON STOCK TO
BE ISSUED IN EACH MERGER OR THE FAIRNESS OR THE MERITS OF EACH MERGER OR HAVE
DETERMINED WHETHER THE INFORMATION CONTAINED IN THIS DOCUMENT IS ACCURATE OR
ADEQUATE. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.


     This proxy statement/prospectus is dated              , 2001. It is first
being mailed to the limited partners on or about        , 2001.


   5




                        PIONEER NATURAL RESOURCES COMPANY



     The world map below reflects the geographic locations of Pioneer Parent's
exploration, development and production operations.


                                     [MAP]


                       WHERE YOU CAN FIND MORE INFORMATION



     Pioneer Parent and each of the 25 partnerships listed below that we call a
reporting partnership file annual, quarterly and special reports, proxy
statements and other information with the Securities and Exchange Commission:




                                                     
Parker & Parsley 82-I, Ltd.                             Parker & Parsley Producing Properties 87-B, Ltd.
Parker & Parsley 82-II, Ltd.                            Parker & Parsley 88-A, L.P.
Parker & Parsley 83-A, Ltd.                             Parker & Parsley 88-B, L.P.
Parker & Parsley 83-B, Ltd.                             Parker & Parsley Producing Properties 88-A, L.P.
Parker & Parsley 84-A, Ltd.                             Parker & Parsley 89-A, L.P.
Parker & Parsley 85-A, Ltd.                             Parker & Parsley 90-A L.P.
Parker & Parsley 85-B, Ltd.                             Parker & Parsley 90-B Conv., L.P.
Parker & Parsley 86-A, Ltd.                             Parker & Parsley 90-B, L.P.
Parker & Parsley 86-B, Ltd.                             Parker & Parsley 90-C Conv., L.P.
Parker & Parsley 86-C, Ltd.                             Parker & Parsley 90-C, L.P.
Parker & Parsley 87-A, Ltd.                             Parker & Parsley 91-A, L.P.
Parker & Parsley 87-B, Ltd.                             Parker & Parsley 91-B, L.P.
Parker & Parsley Producing Properties 87-A, Ltd.





You may read and copy any reports, statements or other information that Pioneer
Parent or any reporting partnership files at the SEC's public reference room at
450 Fifth Street, N.W., Washington, D.C. 20549, or at the SEC's public reference
rooms at 7 World Trade Center, Suite 1300 New York, New York 10048 and at 500
West Madison Street, Suite 1400, Chicago, Illinois 60661. Copies of these
materials may also be obtained from the SEC at prescribed rates by writing to
the Public Reference Section of the Securities and Exchange Commission, 450
Fifth Street, N.W., Washington, D.C. 20549. Please call the SEC at
1-800-SEC-0330 for further information on the public reference rooms. Pioneer
Parent's and each reporting partnership's filings with the SEC are also
available to the public from commercial document retrieval services and at the
web site maintained by the SEC at http://www.sec.gov.



     Pioneer Parent's common stock is listed on the New York Stock Exchange and
the Toronto Stock Exchange, under the symbol "PXD." Pioneer Parent's reports and
other information filed with the SEC can also be inspected at the offices of the
New York Stock Exchange and the Toronto Stock Exchange.



   6


     Pioneer Parent filed a registration statement on Form S-4 to register with
the SEC Pioneer Parent common stock to be issued to the limited partners of each
participating partnership. This document is a part of that registration
statement and constitutes the prospectus of Pioneer Parent in addition to being
the proxy statement of each partnership. As allowed by SEC rules, this document
does not contain all the information you can find in the registration statement
or the exhibits to the registration statement.



     The SEC allows Pioneer Parent to incorporate by reference information into
this document, which means that Pioneer Parent can disclose important
information to you by referring you to another document filed separately with
the SEC. The information incorporated by reference is deemed to be part of this
document, except for any information superseded by information in this document.
This document incorporates by reference the documents set forth below that
Pioneer Parent has previously filed with the SEC and that contain important
information about Pioneer Parent and its finances:



     o    Quarterly Report on Form 10-Q for the three months ended March 31,
          2001



     o    Annual Report on Form 10-K for the year ended December 31, 2000



     o    The description of Pioneer Parent common stock contained in Pioneer
          Parent's registration statement on Form 8-A filed on August 5, 1997,
          as amended by Form 8-A/A filed on August 8, 1997.



     Pioneer Parent is also incorporating by reference additional documents that
it files with the SEC under sections 13(a), 13(c), 14 or 15(d) of the Securities
Exchange Act of 1934 between the date of this document and the date of the
special meeting for each partnership.



     The supplement to this document for each partnership contains financial
information for the partnership. The information supplement for each partnership
constitutes an integral part of this document. Please carefully read the
supplement for each partnership in which you are a limited partner.



     Pioneer Parent has supplied all information contained or incorporated by
reference in this document relating to Pioneer Parent, and each partnership has
supplied all the information contained in this document relating to the
partnership.



     You can obtain any of the documents incorporated by reference through
Pioneer Parent or the SEC. Documents incorporated by reference are available
from Pioneer Parent without charge. Exhibits to the documents will not be sent,
however, unless those exhibits have specifically been incorporated by reference
as exhibits in this document. Limited partners of each partnership may obtain
documents incorporated by reference in this document by requesting them in
writing or by telephone at the following address:



                      Pioneer Natural Resources Company
                      1400 Williams Square West
                      5205 North O'Connor Blvd.
                      Irving, Texas 77039
                      Telephone: (972) 444-9001
                      Attention: Investor Relations



     IF YOU WOULD LIKE TO REQUEST DOCUMENTS FROM PIONEER PARENT OR ANY
PARTNERSHIP IN WHICH YOU OWN AN INTEREST, PLEASE DO SO BY          , 2001
[INSERT 5TH BUSINESS DAY BEFORE MEETING] TO RECEIVE THEM BEFORE THE SPECIAL
MEETING FOR THE PARTNERSHIP.



     You should rely only on the information contained or incorporated by
reference in this document to vote on the merger of each partnership in which
you own an interest. We have not authorized anyone to give any information that
is different from what is contained in this document. This document is dated
        , 2001. You should not assume that the information contained in this
document is accurate as of any date other than that date, and neither the
mailing of this document to you nor the issuance of Pioneer Parent common stock
in the merger of each partnership shall create an implication to the contrary.



   7


                                TABLE OF CONTENTS




                                                                            Page
                                                                            ----
                                                                         
QUESTIONS AND ANSWERS ABOUT THE
   MERGER OF EACH PARTNERSHIP ............................................   iv
SUMMARY ..................................................................    1
RISK FACTORS  ............................................................   18
   Risk Factors Relating to the Merger of Each
   Partnership ...........................................................   18
     The Merger Value for Each Partnership
       Involves Estimates that May Vary
       Materially from the Quantities of Oil and
       Gas Actually Recovered, and
       Consequently Future Net Revenues ..................................   18
     The Merger Value for a Partnership Will Not
       Be Adjusted For Changes in Oil and Gas
       Prices Before the Completion of Its
       Merger ............................................................   18
     The Number of Shares of Pioneer Parent
       Common Stock the Limited Partners of
       Each Partnership Will Receive May
       Decrease Between Now and the
       Completion of the Merger of the
       Partnership .......................................................   18
     Current Market Prices for Oil and Gas
       May Be Higher than the Merger Value
       for a Partnership, Which May Affect
       Deliverability of the Fairness Opinion ............................   18
     You Were Not Independently Represented
       in Establishing the Terms of the Merger
       of Each Partnership ...............................................   18
     The Interests of Pioneer Parent, Pioneer
       USA and Their Directors and Officers
       May Differ From Your Interests ....................................   19
     It Is Unclear What the Market Demand Is
       For Any Partnership or its Assets or
       That the Terms of the Merger of Each
       Partnership Are As Favorable As Could
       Be Obtained in a Third Party Sale .................................   19
     Potential Litigation Challenging the Merger
       of a Partnership May Delay or Block the
       Merger and, As a Result, Your Receipt
       of the Pioneer Parent Common Stock ................................   19
     Repurchase Offers in 2001 by Each of the
       Six Partnerships with a Repurchase
       Obligation were Higher than the Merger
       Value for the Partnership .........................................   19
     You Could be Bound by the Merger of Each
       Partnership in Which You Own an Interest
       Even If You Do Not Vote in Favor of
       the Merger ........................................................   20
   Risks Associated With an Investment in
   Pioneer Parent ........................................................   20
     Limited Partners Who Become Pioneer
       Parent Stockholders Will Own Stock in
       a Corporation Rather than a Limited
       Partnership Interest in a Limited
       Partnership Resulting In a
       Fundamental Change in the
       Nature of Their Investments .......................................   20
     Pioneer Parent Might Not Declare
       Dividends .........................................................   20
     Limited Partners Who Become Pioneer
       Parent Stockholders May Be Diluted ................................   20
     Dividends Paid to Pioneer Parent
       Stockholders Are Taxed at Two Levels ..............................   21
     Pioneer Parent is an Independent Oil
       and Gas Exploration and Development
       Company and Its Business Activities
       Involve Risks .....................................................   21
SPECIAL FACTORS ..........................................................   24
   Background of the Merger of Each Partnership...........................   24
   Reasons for the Merger of Each Partnership ............................   30
   Recommendation of Pioneer USA .........................................   32
   Fairness Opinion ......................................................   33
   Summary Reserve Report ................................................   40
   Alternative Transactions to the Merger of
     Each Partnership ....................................................   41
FORWARD-LOOKING STATEMENTS ...............................................   43
METHOD OF DETERMINING MERGER
   VALUE FOR EACH PARTNERSHIP AND
   AMOUNT OF PIONEER PARENT
   COMMON STOCK OFFERED ..................................................   44
   Components of Merger Value for Each
     Partnership .........................................................   44
   Allocation of Merger Value for Each
     Partnership Among Partners of the
     Partnership .........................................................   45
   Other Methods of Determining Merger
     Values ..............................................................   46
THE MERGER OF EACH PARTNERSHIP ...........................................   47
   General ...............................................................   47
   Legal Opinion for Limited Partners ....................................   47
   Distribution of Pioneer Parent Common Stock ...........................   48
   Fractional Shares .....................................................   48
   Material U.S. Federal Income Tax
     Consequences ........................................................   48
   Accounting Treatment ..................................................   50
   Effect of Debt Owed by a Limited Partner
     to Pioneer USA on Amount of Pioneer
     Parent Common Stock to be Received
     by the Limited Partner ..............................................   50
   Effect of Merger of Each Partnership on
     Limited Partners Who Do Not Vote in
     Favor of the Merger; No Appraisal or
     Dissenters' Rights ..................................................   51
   Future of Nonparticipating Partnerships ...............................   51
   Nonmanaging General Partners of Some
     Partnerships ........................................................   51
   Third Party Offers ....................................................   52
   Merger Amendment ......................................................   52
   Termination of Registration and Reporting
     Requirements ........................................................   52
   Elimination of a Fairness Opinion
     Requirement That Would Otherwise
     Benefit Pioneer USA .................................................   53
   Payment of Expenses and Fees ..........................................   53
THE MERGER AGREEMENT .....................................................   54
   Structure; Effective Time .............................................   54
   Effect of the Merger of Each Partnership ..............................   54
   Conduct of Business Prior to the Merger
     of Each Partnership .................................................   54
   Other Agreements ......................................................   54




                                      -i-
   8





                                                                            Page
                                                                            ----
                                                                         
   Representations and Warranties of
     Pioneer Parent, Pioneer USA and Each
     Partnership .........................................................   55
   Conditions to the Merger of Each Partnership...........................   55
   Termination of the Merger Agreement and
     the Merger of Any Partnership .......................................   56
   Amendments; Waivers ...................................................   57
THE SPECIAL MEETINGS .....................................................   58
   Time and Place; Purpose ...............................................   58
   Record Date; Voting Rights and Proxies ................................   58
   Revocation of Proxies .................................................   59
   Solicitation of Proxies ...............................................   60
   Quorum ................................................................   60
   Required Vote; Broker Non-Votes .......................................   60
   Participation by Assignees ............................................   61
   Special Requirements for Some Limited
     Partners ............................................................   61
   Validity of Proxy Cards ...............................................   61
   Local Laws ............................................................   61
COMPARATIVE PER SHARE MARKET
   PRICE AND DIVIDEND INFORMATION ........................................   62
INTERESTS OF PIONEER PARENT,
   PIONEER USA AND THEIR DIRECTORS
   AND OFFICERS ..........................................................   63
   Conflicting Duties of Pioneer USA, Individually
     and as General Partner ..............................................   63
   Pioneer USA's Employees Provide Services
     to the Partnerships .................................................   63
   Financial Interests of Directors and Officers..........................   63
   The Partnerships Pay Operator Fees to
     Pioneer USA .........................................................   63
OWNERSHIP OF PARTNERSHIP
   INTERESTS .............................................................   64
TRANSACTIONS AMONG ANY
   PARTNERSHIP, PIONEER PARENT,
   PIONEER USA AND THEIR DIRECTORS
   AND OFFICERS ..........................................................   64
MANAGEMENT ...............................................................   66
   Pioneer Parent ........................................................   66
   Pioneer USA ...........................................................   67
PIONEER PARENT ...........................................................   69
   Key Projects to Increase Production ...................................   69
   More Information ......................................................   70
THE PARTNERSHIPS .........................................................   71
   General ...............................................................   71
   The Drilling Partnerships .............................................   71
   The Income Partnerships ...............................................   72
COMPARISON OF RIGHTS OF
   STOCKHOLDERS AND PARTNERS .............................................   73
   General ...............................................................   73
   Summary Comparison of Terms of Shares of
     Pioneer Parent Common Stock and Partnership
     Interests ...........................................................   73
LEGAL MATTERS ............................................................   79
INDEPENDENT AUDITORS AND
   INDEPENDENT PETROLEUM
   CONSULTANTS ...........................................................   79
COMMONLY USED OIL AND
   GAS TERMS .............................................................   81
UNAUDITED PRO FORMA COMBINED
   FINANCIAL STATEMENTS ..................................................  P-1




                               LIST OF APPENDICES




                                                                                 Appendix
                                                                                 --------
                                                                              
General Information Relating to Each Partnership...............................      A
  Table 1     Jurisdiction of Organization, Initial Subscription Price for
              Each Unit, Initial Investment by Limited Partners and Number of
              Limited Partners as of March 31, 2001
  Table 2     Merger Value Attributable to Pioneer USA, Nonmanaging General
              Partners and Limited Partners
  Table 3     Merger Value Attributable to Partnership Interests of Limited
              Partners Per $1,000 Investment
  Table 4     Ownership Percentage and Merger Value Attributable to Nonmanaging
              General Partners Other Than Pioneer USA
  Table 5     Ownership Percentage and Merger Value Attributable to Pioneer USA
              in Its Capacities as General Partner, Nonmanaging General Partner
              and Limited Partner
  Table 6     Voting Percentage and Initial Investment Owned by Pioneer USA in
              Its Capacity as a Limited Partner as of March 31, 2001
  Table 7     Historical Quarterly Partnership Distributions to the Limited
              Partners Per $1,000 Investment from Inception through July 31,
              2001
  Table 8     Annual Repurchase Prices and Aggregate Annual Repurchase Payments
  Table 9     Participation in Costs and Revenues of Each Partnership
  Table 10    Average Oil, Natural Gas Liquids and Gas Sales Prices and
              Production Costs for the Three Months Ended March 31, 2001 and
              2000 and the Years Ended December 31, 2000, 1999 and 1998
  Table 11    Proved Reserves Attributable to Pioneer USA, Nonmanaging General
              Partners and Limited Partners as of December 31, 2000
  Table 12    Partnership Estimated Reserves Attributable to Pioneer USA,
              Nonmanaging General Partners and Limited Partners as of March 31,
              2001
  Table 13    Oil, Natural Gas Liquids and Gas Production for the Three Months
              Ended March 31, 2001 and 2000 and the Years Ended December 31,
              2000, 1999 and 1998




                                      -ii-
   9





                                                                                 Appendix
                                                                                 --------
                                                                              

  Table 14    Productive Wells and Developed Acreage as of March 31, 2001
  Table 15    Recent Trades of Partnership Interests Per $1,000 Investment for
              the Three Months Ended March 31, 2001 and the Years Ended
              December 31, 2000 and 1999
  Table 16    Reserve Value Attributable to Pioneer USA, Nonmanaging General
              Partners and Limited Partners as of March 31, 2001
Summary Reserve Review of Williamson Petroleum Consultants, Inc. for the
Partnerships as of March 31, 2001 [To be provided by Amendment].................     B
Summary Reserve Report of Williamson Petroleum Consultants, Inc. for the
Partnerships as of December 31, 2000............................................     C
Form of Fairness Opinion of Robert A. Stanger & Co., Inc. ......................     D
The Merger Proposals ...........................................................     E
Form of Agreement and Plan of Merger ...........................................     F



     WE HAVE PREPARED A SEPARATE SUPPLEMENT TO THIS DOCUMENT FOR EACH
PARTNERSHIP. EACH SUPPLEMENT INCLUDES:

     o    A TABLE CONTAINING:

          -    THE AGGREGATE INITIAL INVESTMENT BY THE LIMITED PARTNERS

          -    THE AGGREGATE HISTORICAL LIMITED PARTNER DISTRIBUTIONS THROUGH
               JULY 31, 2001


          -    THE MERGER VALUE ATTRIBUTABLE TO PARTNERSHIP INTERESTS OF LIMITED
               PARTNERS, EXCLUDING PIONEER USA



          -    THE MERGER VALUE PER $1,000 LIMITED PARTNER INVESTMENT



          -    THE MERGER VALUE PER $1,000 LIMITED PARTNER INVESTMENT AS A
               MULTIPLE OF DISTRIBUTIONS FOR THE PAST FOUR QUARTERLY
               DISTRIBUTIONS INCLUDING THE DISTRIBUTION IN JULY 2001


          -    THE BOOK VALUE PER $1,000 LIMITED PARTNER INVESTMENT AS OF MARCH
               31, 2001 AND AS OF DECEMBER 31, 2000


          -    THE GOING CONCERN VALUE PER $1,000 LIMITED PARTNER INVESTMENT



          -    THE LIQUIDATION VALUE PER $1,000 LIMITED PARTNER INVESTMENT


          -    THE ORDINARY TAX LOSS PER $1,000 LIMITED PARTNER INVESTMENT IN
               YEAR OF INITIAL INVESTMENT


     o    INFORMATION ABOUT:



          -    THE LEGAL OPINION FOR THE LIMITED PARTNERS



          -    THE TERM OF THE PARTNERSHIP



     o    FOR EACH PARTNERSHIP THAT IS SUBJECT TO THE REPORTING REQUIREMENTS OF
          THE SECURITIES EXCHANGE ACT OF 1934, WHICH WE CALL A REPORTING
          PARTNERSHIP, THE PARTNERSHIP'S QUARTERLY REPORT ON FORM 10-Q,
          INCLUDING MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
          AND RESULTS OF OPERATIONS, FOR THE THREE MONTHS ENDED MARCH 31, 2001


     o    FOR EACH REPORTING PARTNERSHIP, THE PARTNERSHIP'S ANNUAL REPORT ON
          FORM 10-K, INCLUDING MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
          CONDITION AND RESULTS OF OPERATIONS, FOR THE YEAR ENDED DECEMBER 31,
          2000


     o    FOR EACH PARTNERSHIP THAT IS NOT SUBJECT TO THE REPORTING REQUIREMENTS
          OF THE SECURITIES EXCHANGE ACT OF 1934, WHICH WE CALL A NONREPORTING
          PARTNERSHIP, THE PARTNERSHIP'S FINANCIAL STATEMENTS, INCLUDING
          MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
          RESULTS OF OPERATIONS, FOR THE THREE MONTHS ENDED MARCH 31, 2001


     o    FOR EACH NONREPORTING PARTNERSHIP, THE PARTNERSHIP'S FINANCIAL
          STATEMENTS, INCLUDING MANAGEMENT'S DISCUSSION AND ANALYSIS OF
          FINANCIAL CONDITION AND RESULTS OF OPERATIONS, FOR THE YEAR ENDED
          DECEMBER 31, 2000

     o    SELECTED HISTORICAL FINANCIAL DATA FOR THE PARTNERSHIP FOR THE THREE
          MONTHS ENDED MARCH 31, 2001 AND 2000 AND THE FIVE YEARS ENDED DECEMBER
          31, 2000

THE SUPPLEMENT CONSTITUTES AN INTEGRAL PART OF THIS DOCUMENT FOR EACH
PARTNERSHIP. PLEASE CAREFULLY READ ALL OF THE SUPPLEMENTS FOR THE PARTNERSHIPS
IN WHICH YOU ARE A LIMITED PARTNER.


                                      -iii-
   10


           QUESTIONS AND ANSWERS ABOUT THE MERGER OF EACH PARTNERSHIP


Q: HOW DO I VOTE?

A: After reading this document, please fill out and sign your proxy card. Then
mail your signed proxy card in the enclosed return envelope as soon as possible
so that your partnership interests will be represented at the special meeting
for each partnership in which you own an interest.

Q: WHAT HAPPENS IF I DO NOT RETURN A PROXY CARD?

A: The failure to return your proxy card will have the same effect as voting
against the merger for each partnership in which you own an interest.

Q: MAY I VOTE IN PERSON?

A: Yes. You may attend the special meeting for each partnership in which you own
an interest and vote your partnership interests in person, rather than signing
and mailing your proxy card.

Q: MAY I CHANGE MY VOTE AFTER I HAVE MAILED MY SIGNED PROXY CARD?


A: Yes. You may revoke your vote at any time before your proxy is voted at the
special meeting for each partnership in which you own an interest by following
the instructions beginning on page 59. You then may either change your vote by
sending in a new proxy card or by attending the special meeting for each
partnership in which you own an interest and voting in person.


Q: IF MY PARTNERSHIP INTERESTS ARE HELD IN A RETIREMENT ACCOUNT BY A CUSTODIAN,
WILL MY CUSTODIAN VOTE MY PARTNERSHIP INTERESTS FOR ME?

A: Your custodian will not be able to vote your partnership interests. You
should refer to the instructions included on your proxy card to vote your
partnership interests.

Q: SHOULD I SEND IN MY CERTIFICATES FOR MY PARTNERSHIP INTERESTS NOW?


A: No. If the merger of a partnership in which you own an interest is completed,
your certificates representing your partnership interests in that partnership
will be automatically cancelled. We will automatically mail certificates
representing Pioneer Parent common stock issued to you on completion of the
merger of that partnership.


Q: AM I ENTITLED TO APPRAISAL OR DISSENTERS' RIGHTS?

A: No. You will not have any appraisal or dissenters' rights in connection with
the merger of any partnership in which you own an interest.

Q: WHAT HAPPENS TO MY FUTURE CASH DISTRIBUTIONS?


A: Since your partnership interests in participating partnerships will be
cancelled upon completion of the merger of each such partnership, you will not
receive any future distributions on those interests. Pioneer Parent's board of
directors did not declare dividends to the holders of Pioneer Parent common
stock during 1999, 2000 or the three months ended March 31, 2001. The amount of
dividends, if any, paid by Pioneer Parent in the future will depend on business
conditions, its financial condition and earnings, and other factors.


Q: WHO CAN HELP ANSWER MY QUESTIONS?


A: If you have any questions about the merger of any of the partnerships in
which you own an interest, please call Pioneer Parent's information agent, D.F.
King & Co., Inc., at (XXX) XXX-XXXX.



                                      -iv-
   11
                                     SUMMARY


     To understand the merger of each partnership in which you own an interest
and to obtain a more detailed description of the legal terms of each such
merger, you should carefully read this entire document, the related partnership
supplements, and the documents described in "Where You Can Find More
Information" on the inside front cover page of this document . For definitions
of oil and gas terms used in this document, see "Commonly Used Oil and Gas
Terms" on page 81.



     When we use the terms "Pioneer USA," "we," "us" or "our," we are referring
to your sole or managing general partner, Pioneer Natural Resources USA, Inc.,
including its consolidated subsidiaries and predecessors, unless the context
otherwise requires. When we use the term "Pioneer Parent," we are referring to
Pioneer Natural Resources Company. When we use the term "merger proposals," we
are referring to the proposals to approve the merger agreement, the merger
amendment, the selection of special legal counsel for the limited partners and
the legal opinion of that counsel. When we use the term "participating
partnership," we are referring to each partnership the limited partners of which
approve the merger proposals.


                                   THE MERGERS


     Pioneer Parent proposes to acquire each partnership by merging each
partnership into us. We will be the survivor of each merger. The partnership
interests of each participating partnership, other than our interests, will be
converted into Pioneer Parent common stock.



     The number of shares of common stock Pioneer Parent will offer for all
partnership interests of a participating partnership will be based on (1) the
merger value for the partnership as described below and (2) the average closing
price of the Pioneer Parent common stock, as reported by the New York Stock
Exchange, for the ten trading days ending three business days before the initial
date of the special meeting for the partnership. Pioneer Parent and Pioneer USA
determined the merger value for each partnership primarily based on the present
value of estimated future net revenues from the partnership's estimated oil and
gas reserves at March 31, 2001, which was reviewed by Williamson Petroleum
Consultants, Inc. as of March 31, 2001. Pioneer Parent and Pioneer USA used
the following parameters in calculating the present value of estimated future
net revenues: (1) a five-year New York Mercantile Exchange, or NYMEX, futures
price for oil and gas as of March 30, 2001 with prices held constant after year
five at the year five price, less standard industry adjustments, (2) historical
operating costs adjusted only for those items affected by commodity prices, such
as production taxes and ad valorem taxes, and (3) a 10.0% discount rate. For
2001, the oil and gas prices were based on the average NYMEX futures price for
the nine-month period beginning on April 1, 2001 and ending December 31, 2001.
See the table on page 6 for the NYMEX futures prices. See "Method of Determining
Merger Value For Each Partnership and Amount of Pioneer Parent Common Stock
Offered -- Components of Merger Value For Each Partnership" on page 44 of this
document for information on the basis of pricing. In addition, each
partnership's merger value includes its net working capital as of March 31,
2001, less its pro rata share, based on its reserve value, of the estimated
expenses and fees of the mergers of all of the partnerships and less the cash
distribution to be mailed on or about July 12, 2001, by the partnership to its
partners. The Pioneer Parent common stock will be allocated among the partners
of a participating partnership based on the liquidation provisions of the
partnership agreement of the partnership.



     On pages 4 and 5 of this document is a table that shows important
information about each partnership, including the amount of Pioneer Parent
common stock that will be offered in the merger for each $1,000 of initial
investment for that partnership. For purposes of illustration in this document,
we have calculated the number of shares to be issued based on an assumed average
closing price of $18.00 per share of Pioneer Parent common stock. Prior to the
date of the special meeting for each partnership, we will update the number of
shares to be issued using the actual average closing price of Pioneer Parent
common stock for the ten trading days ending three business days before the
initial date of the special meeting.



     Pioneer Parent and Pioneer USA agreed to structure the transaction as a
merger of each partnership instead of as a property sale followed by liquidation
of each partnership because the merger will:


     o    require fewer legal documents;

     o    reduce filing fees and other costs; and


     o    result in the same amount of Pioneer Parent common stock to the
          limited partners as would a property sale and liquidation using the
          same commodity prices.



     Pioneer Parent and Pioneer USA expect to sign the merger agreement as soon
as the Securities and Exchange Commission declares effective under the
Securities Act of 1933 the registration statement that includes this document.
However, if the oil and gas commodity prices materially increase or decrease
from the prices used in calculating the merger value for any partnership,
Pioneer Parent or Pioneer USA might abandon the proposed merger of the
partnership before submitting the merger proposals to the limited partners for
approval. In addition, Pioneer Parent may abandon the proposed merger of any or
all of the partnerships at any time prior to the special meeting for any such
partnership for any reason including changes in, among other things, the price
of Pioneer Parent common stock, the market prices for oil and gas generally or
the oil and gas industry generally.




   12


                                  THE COMPANIES

PIONEER NATURAL RESOURCES COMPANY
1400 Williams Square West
5205 North O'Connor Blvd.
Irving, Texas 75039
(972) 444-9001


     Pioneer Parent is a large, independent exploration and production company
with total proved reserves equivalent to 3.8 trillion cubic feet of natural gas,
or 628 million barrels of oil. Pioneer Parent's proved reserves are balanced
equally between natural gas and oil, and Pioneer Parent has a
reserves-to-production ratio of 14 years. Sixty-seven percent of Pioneer
Parent's proved reserves are in three U.S. areas: the Hugoton gas field, the
West Panhandle gas field, and the Spraberry oil and natural gas field. Pioneer
Parent also has properties in East Texas, the Gulf Coast, and the offshore Gulf
of Mexico as well as in Argentina, Canada, South Africa, and Gabon. Pioneer
Parent seeks to increase net asset value and production by combining lower risk
development drilling with higher-risk exploration activity.



     Pioneer Parent's common stock is traded on the New York Stock Exchange and
the Toronto Stock Exchange under the symbol "PXD." Pioneer Parent prepared this
document to offer its common stock to you. See "Pioneer Parent" on page 69 of
this document for more information about Pioneer Parent.



     Pioneer Parent files annual, quarterly and special reports, proxy
statements and other information with the Securities and Exchange Commission.
Those SEC filings are available to you in the same manner as each reporting
partnership's information. See "Where You Can Find More Information" on the
inside front cover page of this document.


PIONEER NATURAL RESOURCES USA, INC.
1400 Williams Square West
5205 North O'Connor Blvd.
Irving, Texas 75039
(972) 444-9001


     We prepared this document to solicit your proxy. We are a 100% owned
subsidiary of Pioneer Parent. We directly own almost all of Pioneer Parent's
United States oil and gas properties.


THE PARTNERSHIPS
c/o Pioneer Natural Resources USA, Inc.
1400 Williams Square West
5205 North O'Connor Blvd.
Irving, Texas 75039
(972) 444-9001


     The name of each partnership is found in the table beginning on page 4.
Each partnership produces and sells oil and gas. Each partnership was formed to
provide the general and limited partners cash flow from operations and, except
for Parker & Parsley Producing Properties 87-A, Ltd., Parker & Parsley Producing
Properties 87-B, Ltd. and Parker & Parsley Producing Properties 88-A, L.P., a
one time deduction for intangible drilling and development costs. See the
supplement to this document for each of your partnerships for specific
information about the partnership, including the merger value as a multiple of
distributions for the past four quarterly distributions including the
distribution in July 2001. As a result of each partnership's oil and gas
operations, each partnership distributes cash to the limited and general
partners from the partnership's net cash flows. These distributions are made
quarterly, unless sufficient cash is not available.



     The partnerships' properties consist of interests in approximately 1,100
oil and gas wells that are located primarily in the Spraberry field of the
Permian Basin of West Texas. We operate approximately 92% of the partnerships'
wells. At December 31, 2000, the partnerships' combined total proved reserves
were 33.6 million barrels of oil equivalent, or MMBOE, consisting of 27.3
million barrels, or MMBbls, of oil and natural gas liquids and 37.6 billion
cubic feet, or Bcf, of natural gas. Approximately 93% of the reserves are
attributable to the limited partners' partnership interests, excluding
partnership interests we directly own. Approximately 81% of the total proved
reserves attributable to the properties are oil and liquids, and 19% are natural
gas, based on six Mcf of gas being equivalent to one Bbl of oil. See "The
Partnerships" on page 71 of this document for more information about the
partnerships.



                                  RISK FACTORS



     You should carefully consider the risks relating to the merger of each
partnership in which you own an interest described in "Risk Factors" beginning
on page 17 of this document. These include:



o    The merger value for the partnership determines the amount of Pioneer
     Parent common stock you will receive in the merger of the partnership.
     Pioneer Parent and Pioneer USA determined each merger value and will not
     adjust it for changes in partnership value before the merger is completed.



o    You were not independently represented in establishing the terms of any
     merger.



o    Our board of directors had conflicting interests in evaluating each merger
     because each member of our board of directors is also an officer of Pioneer
     Parent.



o    Repurchase offers in 2001 by each of the six partnerships with a repurchase
     obligation were higher than the merger value for the partnership.



o    Limited partners who become Pioneer Parent stockholders will own stock in a
     corporation rather than a limited partnership interest in a limited
     partnership resulting in a fundamental change in the nature of their
     investments.


                        SUMMARY TABLE -- MERGER VALUE AND
                        AMOUNT OF INITIAL LIMITED PARTNER
                                INVESTMENT REPAID

     The table on pages 4 and 5 contains the following summary information for
each partnership:


                                      -2-
   13


o    the merger value attributable to:


     -    Pioneer USA's partnership interests, whether general or limited;

     -    the partnership interests of the unaffiliated limited partners of the
          nonmanaging general partner, if any, of each partnership;


     -    the limited partners' partnership interests, including the estimated
          number of shares of Pioneer Parent common stock offered to the limited
          partners other than Pioneer USA;


o    for each $1,000 initial limited partner investment in the partnership:


     -    the estimated number of shares of Pioneer Parent common stock offered;


     -    the merger value;


     -    the total historical cash distributions through July 31, 2001; and


     -    the total amount of initial investment by the limited partners that
          has been repaid, after giving effect to the merger of the partnership,
          stated in dollars and as a percentage; and

o    the aggregate reserve value attributable to the limited partners other than
     Pioneer USA per barrel of oil equivalent, or BOE.


     This information is based on assumptions, including the following:



o    Pioneer Parent and Pioneer USA engaged Williamson Petroleum Consultants,
     Inc. to review the estimates of each partnership's reserves as of March 31,
     2001.



o    Pioneer Parent and Pioneer USA estimated the present value of estimated
     future net revenues for each partnership from the estimated reserves for
     each partnership at March 31, 2001. Pioneer Parent and Pioneer USA used the
     following parameters in calculating the present value of estimated future
     net revenues: (1) a five-year NYMEX futures price for oil and gas as of
     March 30, 2001, with prices held constant after year five at the year five
     price, less standard industry adjustments, (2) historical operating costs
     adjusted only for those items affected by commodity prices, such as
     production taxes and ad valorem taxes, and (3) a discount rate of 10.0%.



See "Method of Determining Merger Value for Each Partnership and Amount of
Pioneer Parent Common Stock Offered - Components of Merger Value for Each
Partnership."



     You should read the following table together with the detailed information
in Table 2 and Table 3 of Appendix A to this document. For purposes of
illustration in this document, we have calculated the number of shares to be
issued based on an assumed average closing price of $18.00 per share of Pioneer
Parent common stock. Prior to the date of the special meeting for each
partnership, we will update the number of shares to be issued using the actual
average closing price of Pioneer Parent common stock for the ten trading days
ending three business days before the initial date of the special meeting.


     Interests in some partnerships were sold in units at prices other than
$1,000. We have presented this information based on a $1,000 initial investment
for ease of use and comparison among partnerships. You should not assume that
the amount shown per $1,000 investment is the same as the value or amount
attributable to a single unit investment. See Table 1 of Appendix A to this
document for the initial subscription price for each unit.


                                      -3-
   14

           SUMMARY TABLE -- MERGER VALUE AND AMOUNT OF INITIAL LIMITED
                            PARTNER INVESTMENT REPAID





                                                      ------------------------------------------------------------------------------
                                                                                     MERGER VALUE
                                                      ------------------------------------------------------------------------------
                                                                                                    LIMITED PARTNERS
                                                                                     -----------------------------------------------
                                                                      NONMANAGING
                                                         PIONEER        GENERAL
                                                           USA          PARTNERS
                                                      -------------  -------------     AGGREGATE          LESS
                                                          MERGER         MERGER          MERGER         JULY 2001         MERGER
                                                          VALUE          VALUE           VALUE        DISTRIBUTIONS        VALUE
                                                      -------------  -------------   -------------    -------------    -------------
                                                                                                        
PARKER & PARSLEY 81-I, LTD.                           $     225,691  $      16,187   $     680,747    $     (51,812)   $     628,935
PARKER & PARSLEY 81-II, LTD.                                142,209          5,774         510,262          (40,512)         469,750
PARKER & PARSLEY 82-I, LTD.                                 384,588         13,293         921,471          (77,867)         843,604
PARKER & PARSLEY 82-II, LTD.                                417,948         12,957       1,258,424          (59,442)       1,198,982
PARKER & PARSLEY 82-III, LTD.                               305,950          9,928         837,663          (49,940)         787,723
PARKER & PARSLEY 83-A, LTD.                                 940,944         37,001       2,824,140         (161,154)       2,662,986
PARKER & PARSLEY 83-B, LTD.                               1,233,793         48,095       3,657,507         (184,534)       3,472,973
PARKER & PARSLEY 84-A, LTD.                               1,285,776         56,545       4,068,298         (237,861)       3,830,437
PARKER & PARSLEY 85-A, LTD.                                  41,068             --       1,450,480          (87,918)       1,362,562
PARKER & PARSLEY 85-B, LTD.                                  20,207             --       1,232,802          (77,401)       1,155,401
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.               50,076             --       1,514,330          (81,105)       1,433,225
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.        24,401             --         960,832          (77,690)         883,142
PARKER & PARSLEY 86-A, LTD.                                  24,320             --       1,798,787          (10,918)       1,787,869
PARKER & PARSLEY 86-B, LTD.                                  67,657             --       4,055,061         (226,314)       3,828,747
PARKER & PARSLEY 86-C, LTD.                                  41,133             --       3,381,735         (276,941)       3,104,794
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                 12,640             --       1,334,081          (82,767)       1,251,314
PARKER & PARSLEY 87-A CONV., LTD.                            14,150             --         788,572          (57,434)         731,138
PARKER & PARSLEY 87-A, LTD.                                  88,920             --       5,894,403         (430,459)       5,463,944
PARKER & PARSLEY 87-B CONV., LTD.                            12,012             --       1,051,036          (63,086)         987,950
PARKER & PARSLEY 87-B, LTD.                                  49,926             --       4,294,068         (257,587)       4,036,481
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.             35,132             --       2,816,163         (246,164)       2,569,999
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.             62,154             --       2,452,316         (116,244)       2,336,072
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                 29,502             --       3,127,660         (206,933)       2,920,727
PARKER & PARSLEY 88-A CONV., L.P.                            21,672             --         994,896          (76,370)         918,526
PARKER & PARSLEY 88-A, L.P.                                  74,684             --       3,399,201         (260,389)       3,138,812
PARKER & PARSLEY 88-B CONV., L.P.                            18,200             --       1,227,494          (67,356)       1,160,138
PARKER & PARSLEY 88-B, L.P.                                  59,211             --       3,009,326         (165,038)       2,844,288



                                                       -----------------    ---------------------------------------------
                                                         MERGER VALUE       PER $1,000 INITIAL LIMITED PARTNER INVESTMENT
                                                       -----------------    ---------------------------------------------
                                                       LIMITED PARTNERS
                                                       -----------------
                                                           ESTIMATED          ESTIMATED
                                                            NUMBER OF           NUMBER OF                  DISTRIBUTIONS
                                                            SHARES OF           SHARES OF                      FROM
                                                             PIONEER             PIONEER                     INCEPTION
                                                             COMMON              COMMON          MERGER       THROUGH
                                                        STOCK OFFERED(a)    STOCK OFFERED(a)      VALUE       7/31/01
                                                        ----------------    ----------------   ----------   ----------
                                                                                                
PARKER & PARSLEY 81-I, LTD.                                  34,941                5.01        $    90.13   $   657.13
PARKER & PARSLEY 81-II, LTD.                                 26,098                4.07             73.34       841.87
PARKER & PARSLEY 82-I, LTD.                                  46,867                4.45             80.06       985.93
PARKER & PARSLEY 82-II, LTD.                                 66,611                5.65            101.61     1,141.98
PARKER & PARSLEY 82-III, LTD.                                43,763                6.76            121.72       985.34
PARKER & PARSLEY 83-A, LTD.                                 147,944                7.86            141.43     1,328.26
PARKER & PARSLEY 83-B, LTD.                                 192,943                8.58            154.41     1,532.16
PARKER & PARSLEY 84-A, LTD.                                 212,803               11.19            201.43     1,471.45
PARKER & PARSLEY 85-A, LTD.                                  75,698                8.03            144.55       757.31
PARKER & PARSLEY 85-B, LTD.                                  64,189                8.09            145.70       954.81
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.               79,624               16.32            293.69     1,131.64
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.        49,064               10.64            191.57       967.15
PARKER & PARSLEY 86-A, LTD.                                  99,327                9.84            177.09     1,360.62
PARKER & PARSLEY 86-B, LTD.                                 212,709               12.45            224.17     1,575.72
PARKER & PARSLEY 86-C, LTD.                                 172,489                8.96            161.23     1,486.92
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                 69,518               14.13            254.33     1,634.33
PARKER & PARSLEY 87-A CONV., LTD.                            40,619               10.63            191.35     1,332.03
PARKER & PARSLEY 87-A, LTD.                                 303,553               10.60            190.81     1,332.10
PARKER & PARSLEY 87-B CONV., LTD.                            54,887               11.18            201.25     1,251.46
PARKER & PARSLEY 87-B, LTD.                                 224,249               11.19            201.38     1,251.53
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.            142,778               11.73            211.17     1,000.38
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.            129,782               21.64            389.51     1,127.05
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                162,263               15.48            278.69     1,575.74
PARKER & PARSLEY 88-A CONV., L.P.                            51,030               13.63            245.40     1,120.44
PARKER & PARSLEY 88-A, L.P.                                 174,379               13.66            245.95     1,120.54
PARKER & PARSLEY 88-B CONV., L.P.                            64,453               17.82            320.83     1,129.70
PARKER & PARSLEY 88-B, L.P.                                 158,016               17.83            321.02     1,129.74


                                                    --------------------------
                                                       PER $1,000 INITIAL
                                                    LIMITED PARTNER INVESTMENT
                                                    --------------------------



                                                             AMOUNT OF            LIMITED
                                                        INITIAL INVESTMENT       PARTNERS'
                                                               REPAID            AGGREGATE
                                                       ---------------------   RESERVE VALUE
                                                           $            %         PER BOE
                                                       ----------    -------   -------------
                                                                      
PARKER & PARSLEY 81-I, LTD.                            $   747.26     74.73%      $  3.92
PARKER & PARSLEY 81-II, LTD.                               915.21     91.52%         3.42
PARKER & PARSLEY 82-I, LTD.                              1,065.99    106.60%         3.50
PARKER & PARSLEY 82-II, LTD.                             1,243.59    124.36%         4.05
PARKER & PARSLEY 82-III, LTD.                            1,107.06    110.71%         3.83
PARKER & PARSLEY 83-A, LTD.                              1,469.69    146.97%         3.53
PARKER & PARSLEY 83-B, LTD.                              1,686.57    168.66%         3.53
PARKER & PARSLEY 84-A, LTD.                              1,672.88    167.29%         3.55
PARKER & PARSLEY 85-A, LTD.                                901.86     90.19%         3.82
PARKER & PARSLEY 85-B, LTD.                              1,100.51    110.05%         4.01
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.           1,425.33    142.53%         4.39
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.    1,158.72    115.87%         3.81
PARKER & PARSLEY 86-A, LTD.                              1,537.71    153.77%         3.80
PARKER & PARSLEY 86-B, LTD.                              1,799.89    179.99%         4.14
PARKER & PARSLEY 86-C, LTD.                              1,648.15    164.82%         3.76
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.             1,888.66    188.87%         4.00
PARKER & PARSLEY 87-A CONV., LTD.                        1,523.38    152.34%         4.03
PARKER & PARSLEY 87-A, LTD.                              1,522.91    152.29%         4.06
PARKER & PARSLEY 87-B CONV., LTD.                        1,452.71    145.27%         3.92
PARKER & PARSLEY 87-B, LTD.                              1,452.91    145.29%         3.92
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.         1,211.55    121.16%         3.90
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.         1,516.56    151.66%         4.19
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.             1,854.43    185.44%         3.87
PARKER & PARSLEY 88-A CONV., L.P.                        1,365.84    136.58%         4.04
PARKER & PARSLEY 88-A, L.P.                              1,366.49    136.65%         4.04
PARKER & PARSLEY 88-B CONV., L.P.                        1,450.53    145.05%         4.21
PARKER & PARSLEY 88-B, L.P.                              1,450.76    145.08%         4.21




                                      -4-
   15





                                                      ------------------------------------------------------------------------------
                                                                                     MERGER VALUE
                                                      ------------------------------------------------------------------------------
                                                                                                    LIMITED PARTNERS
                                                                                     -----------------------------------------------
                                                                      NONMANAGING
                                                         PIONEER        GENERAL
                                                           USA          PARTNERS
                                                      -------------  -------------     AGGREGATE          LESS
                                                          MERGER         MERGER          MERGER         JULY 2001         MERGER
                                                          VALUE          VALUE           VALUE        DISTRIBUTIONS        VALUE
                                                      -------------  -------------   -------------    -------------    -------------
                                                                                                        
PARKER & PARSLEY 88-C CONV., L.P.                            12,256             --         996,336          (58,700)         937,636
PARKER & PARSLEY 88-C, L.P.                                   8,093             --         706,148          (41,872)         664,276
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.             34,210             --       2,107,964         (115,652)       1,992,312
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                 34,558             --       3,624,600         (203,402)       3,421,198
PARKER & PARSLEY 89-A CONV., L.P.                             9,323             --         981,521          (58,543)         922,978
PARKER & PARSLEY 89-A, L.P.                                  62,481             --       2,886,522         (171,882)       2,714,640
PARKER & PARSLEY 89-B CONV., L.P.                            23,671             --       1,897,795         (119,915)       1,777,880
PARKER & PARSLEY 89-B, L.P.                                  40,152             --       2,073,108         (131,168)       1,941,940
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                 30,131             --       2,028,263         (128,040)       1,900,223
PARKER & PARSLEY 90-A CONV., L.P.                             9,110             --         608,388          (43,633)         564,755
PARKER & PARSLEY 90-A, L.P.                                  52,103             --       1,732,967         (123,996)       1,608,971
PARKER & PARSLEY 90-B CONV., L.P.                            53,040             --       3,371,528         (240,352)       3,131,176
PARKER & PARSLEY 90-B, L.P.                                 108,517             --       9,195,042         (654,545)       8,540,497
PARKER & PARSLEY 90-C CONV., L.P.                            25,877             --       1,944,137         (114,157)       1,829,980
PARKER & PARSLEY 90-C, L.P.                                  36,317             --       3,122,419         (183,844)       2,938,575
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                 53,018             --       3,609,423         (222,982)       3,386,441
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.             15,154             --       1,616,753         (116,477)       1,500,276
PARKER & PARSLEY 91-A, L.P.                                  65,151             --       4,950,064         (305,711)       4,644,353
PARKER & PARSLEY 91-B, L.P.                                  54,733             --       5,259,991         (284,171)       4,975,820
                                                      -------------  -------------   -------------    -------------    -------------
                                                      $   6,411,859  $     199,780   $ 112,254,724    $  (7,050,278)   $ 105,204,446
                                                      =============  =============   =============    =============    =============





                                                       -----------------    ---------------------------------------------
                                                         MERGER VALUE       PER $1,000 INITIAL LIMITED PARTNER INVESTMENT
                                                       -----------------    ---------------------------------------------
                                                       LIMITED PARTNERS
                                                       -----------------
                                                           ESTIMATED          ESTIMATED
                                                            NUMBER OF           NUMBER OF                  DISTRIBUTIONS
                                                            SHARES OF           SHARES OF                      FROM
                                                             PIONEER             PIONEER                     INCEPTION
                                                             COMMON              COMMON          MERGER       THROUGH
                                                        STOCK OFFERED(a)    STOCK OFFERED(a)      VALUE       7/31/01
                                                        ----------------    ----------------   ----------   ----------
                                                                                                
PARKER & PARSLEY 88-C CONV., L.P.                            52,091               15.32            275.69     1,052.80
PARKER & PARSLEY 88-C, L.P.                                  36,905               15.21            273.81     1,052.39
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.            110,684               19.86            357.55     1,234.73
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                190,067               19.08            343.50     1,185.95
PARKER & PARSLEY 89-A CONV., L.P.                            51,277               18.33            329.99     1,070.24
PARKER & PARSLEY 89-A, L.P.                                 150,814               18.37            330.57     1,070.30
PARKER & PARSLEY 89-B CONV., L.P.                            98,772               15.71            282.79       931.42
PARKER & PARSLEY 89-B, L.P.                                 107,886               15.69            282.39       931.43
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                105,568               15.04            270.69       800.47
PARKER & PARSLEY 90-A CONV., L.P.                            31,376               13.38            240.83       909.70
PARKER & PARSLEY 90-A, L.P.                                  89,388               13.41            241.44       909.76
PARKER & PARSLEY 90-B CONV., L.P.                           173,955               14.72            264.97       736.72
PARKER & PARSLEY 90-B, L.P.                                 474,473               14.74            265.39       736.80
PARKER & PARSLEY 90-C CONV., L.P.                           101,666               13.55            243.96       657.33
PARKER & PARSLEY 90-C, L.P.                                 163,255               13.51            243.26       657.33
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                188,136               17.24            310.40       823.21
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.             83,349               16.03            288.51       760.35
PARKER & PARSLEY 91-A, L.P.                                 258,020               22.29            401.24       854.43
PARKER & PARSLEY 91-B, L.P.                                 276,435               24.60            442.73       737.60
                                                          ---------              ------        ----------   ----------
                                                          5,844,714              613.50        $11,043.53   $49,296.29
                                                          =========              ======        ==========   ==========


                                                    --------------------------
                                                       PER $1,000 INITIAL
                                                    LIMITED PARTNER INVESTMENT
                                                    --------------------------



                                                             AMOUNT OF            LIMITED
                                                        INITIAL INVESTMENT       PARTNERS'
                                                               REPAID            AGGREGATE
                                                       ---------------------   RESERVE VALUE
                                                           $            %         PER BOE
                                                       ----------    -------   -------------
                                                                      

PARKER & PARSLEY 88-C CONV., L.P.                        1,328.49    132.85%         4.13
PARKER & PARSLEY 88-C, L.P.                              1,326.20    132.62%         4.13
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.         1,592.28    159.23%         4.23
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.             1,529.45    152.95%         4.33
PARKER & PARSLEY 89-A CONV., L.P.                        1,400.23    140.02%         4.35
PARKER & PARSLEY 89-A, L.P.                              1,400.87    140.09%         4.35
PARKER & PARSLEY 89-B CONV., L.P.                        1,214.21    121.42%         4.08
PARKER & PARSLEY 89-B, L.P.                              1,213.82    121.38%         4.08
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.             1,071.16    107.12%         4.27
PARKER & PARSLEY 90-A CONV., L.P.                        1,150.53    115.05%         4.19
PARKER & PARSLEY 90-A, L.P.                              1,151.20    115.12%         4.19
PARKER & PARSLEY 90-B CONV., L.P.                        1,001.69    100.17%         4.26
PARKER & PARSLEY 90-B, L.P.                              1,002.19    100.22%         4.25
PARKER & PARSLEY 90-C CONV., L.P.                          901.29     90.13%         4.19
PARKER & PARSLEY 90-C, L.P.                                900.59     90.06%         4.19
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.             1,133.61    113.36%         4.34
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.         1,048.86    104.89%         3.78
PARKER & PARSLEY 91-A, L.P.                              1,255.67    125.57%         4.52
PARKER & PARSLEY 91-B, L.P.                              1,180.33    118.03%         4.61
                                                       ----------
                                                       $60,339.82
                                                       ==========




---------------

(a)  For this preliminary document, the number of shares of Pioneer common stock
     offered is based upon an assumed average closing price of $18.00 per share
     of Pioneer common stock.

                                      -5-
   16
                              NYMEX FUTURES PRICES

     The following table shows the NYMEX futures price for oil and gas as of
March 30, 2001, which Pioneer Parent and Pioneer USA used in the calculation of
the reserve value portion of the merger value for each partnership:



         DATE               OILS ($/Bbl)        GAS ($/Mcf)(1)
    --------------          ------------        --------------
                                          
    Apr - Dec 2001             26.17                  5.18
         2002                  24.36                  4.61
         2003                  22.83                  4.16
         2004                  22.31                  4.09
         2005                  21.97                  4.12
      Thereafter               21.97                  4.12


----------

(1)  The NYMEX price for gas is quoted in dollars per million British thermal
     units, or MMBTU. We converted those prices to dollars per thousand cubic
     feet, or Mcf.

     The reserve value portion of the merger value for each partnership was
calculated using a 10.0% discount rate.

       EXAMPLE CALCULATION OF MERGER VALUE FOR PARKER & Parsley 81-I, Ltd.



                                                                            
Merger value for limited partners:
     Reserve value (Table 16 of Appendix A to this document)   (1)    $   627,135
     Plus working capital value                                (2)         65,041
     Less estimated merger expenses and fees                   (3)        (11,429)
                                                                      -----------
     Aggregate merger value (page 4 of this document)                     680,747
     Less July 2001 distribution                               (4)        (51,812)
                                                                      -----------
     Merger value (page 4 of this document and Table 2 of
     Appendix A to this document)                              (5)    $   628,935
                                                                      ===========

Initial investment:
     Initial investment by limited partners (Table 1 of
     Appendix A to this document)                                     $ 7,410,000
     Less initial investment by Pioneer USA (Table 6 of
     Appendix A to this document)                                         433,000
                                                                      -----------
     Initial investment without Pioneer USA                           $ 6,977,000
                                                                      ===========

Number of per $1,000 limited partner investments:              (6)          6,977
                                                                      ===========

Per $1,000 limited partner investment as set forth in Table
3 of Appendix A to this document:
     Reserve value                                                    $     89.88   (1) divided by (6)
     Working capital value                                                   9.32   (2) divided by (6)
     Less estimated merger expenses and fees                                (1.64)  (3) divided by (6)
                                                                      -----------
     Aggregate merger value                                                 97.56
     Less July 2001 distribution                                            (7.43)  (4) divided by (6)
                                                                      -----------
     Merger value                                                     $     90.13
                                                                      ===========

Aggregate number of shares of Pioneer Parent common stock
offered to limited partners of the partnership before
rounding                                                                34,940.83   (5) divided by $18.00
                                                                      ===========
Aggregate number of shares of Pioneer Parent common stock
offered to limited partners of the partnership rounded up to
the nearest whole share                                        (7)         34,941
                                                                      ===========

Number of shares of Pioneer Parent common stock offered per
$1,000 limited partner investment                                            5.01   (7) divided by (6)
                                                                      ===========




                                      -6-
   17



               BENEFITS AND DISADVANTAGES TO THE LIMITED PARTNERS


     We believe the merger of each partnership provides the following benefits
to the limited partners of the partnership:

     Liquidity. None of the partnership interests of any of the partnerships are
traded on a national stock exchange or in any other significant market. No
liquid market exists for interests in any of the partnerships. Although some
partnership interests are occasionally sold in private or an informal secondary
market for limited partner securities, we believe the potential buyers in such
transactions are few and the prices generally reflect a significant discount for
illiquidity. See Table 15 of Appendix A for historical information about recent
trades of partnership interests in each partnership. Repurchase obligations
exist in only a few of the partnerships and are limited in both amount and price
by formula in the partnership agreements. See Table 8 of Appendix A for
repurchase information.


     The merger of each partnership provides liquidity to the limited partners
of that partnership at a price based on oil and gas reserve values, not on
limited market demand for illiquid partnership interests. All limited partners
of a participating partnership will receive Pioneer Parent common stock in
exchange for their partnership interests shortly after completion of the merger
of the partnership. Shares of Pioneer Parent common stock are freely
transferable and listed on the New York Stock Exchange and the Toronto Stock
Exchange. On April 16, 2001, the last full trading day prior to the announcement
of the proposed merger of each partnership, the last reported sales price of
Pioneer Parent common stock, as reported by the New York Stock Exchange, was
$17.27.



     Oil and Gas Investment Vehicle. Pioneer Parent's common stock provides an
oil and gas investment vehicle that we believe will be advantageous to the
partnership interests in each partnership because:



o    Expansion and Balancing of Reserves. The limited partners will have the
     opportunity to benefit from Pioneer Parent's efforts (1) to expand its
     reserve base through acquisitions and development or exploratory drilling,
     and (2) to maintain a strategic balance between oil and natural gas
     reserves. At December 31, 2000, Pioneer Parent's reserve mix was 50% oil
     and NGLs and 50% natural gas compared to the combined partnerships' reserve
     mix of 81% oil and NGLs and 19% natural gas at such date.



o    Geographic Diversification and Larger Oil and Gas Reserve Base. By
     combining each participating partnership into a single ownership entity,
     the merger of the partnership provides the limited partners of the
     partnership with an investment portfolio substantially larger and more
     geographically diversified than the portfolio of the partnership
     individually. This increased size and the resulting consolidation of
     operations spread the risk of an investment in Pioneer Parent over a
     broader group of assets and reduces the dependence of the investment upon
     the performance of any particular asset or group of assets, such as assets
     in the same geographical area.



     Liquidation Value. The merger value for each partnership is based on the
value of the underlying properties, which we believe is essentially the same
value or a higher value than that could be achieved by selling the partnership's
property interests and liquidating the partnership at that time. In addition, we
believe that the value of Pioneer Parent common stock to be distributed to each
limited partner in the merger of each partnership is higher than what the
limited partners would otherwise receive over the life of the partnership,
assuming the same oil and gas commodity prices and operating costs as used to
determine the reserve value for each partnership and giving effect to the time
value of money, for the following reasons:


o    The partnership agreement for each partnership requires cash distributions
     to be reduced by general and administrative expenses allocable to the
     partnership. The merger value for each partnership reflects a liquidation
     value based on a reserve value that has not been reduced for general and
     administrative expenses.


o    The merger value for each partnership is based primarily upon the reserve
     value for the partnership, which was determined using recent NYMEX futures
     oil and gas prices that are, on average, higher than historical oil and gas
     prices. It is likely that actual oil and gas prices will vary often and
     possibly widely, as has been demonstrated historically, from the prices
     used to prepare these estimates. Although future oil and gas prices could
     be higher than the prices on March 30, 2001 which were used in calculating
     the merger value for each partnership, using a fixed date for determining
     the merger value for each partnership eliminates the potential loss in
     value that could occur if oil and gas prices decline.



     Acceleration of Realization of Value. Pioneer Parent's common stock
provides the limited partners of each participating partnership with liquidity
earlier than if the limited partners remain in the partnership and receive the
expected ordinary cash distributions from oil and gas production. Because each
partnership's properties are mature producing properties, we believe that
production from those properties will continue to decline at the rate predicted
in the partnership's oil and gas engineering reserve reports. Accordingly, cash
distributions from each partnership are also expected to decline, subject to
variation for changes in oil and gas prices.


     Elimination of Partnership Tax Reports. The merger of each participating
partnership will eliminate the limited partners' Schedule K-1 tax reports for
the partnership for tax years after the merger occurs. This is expected to
simplify the limited partners' individual tax return preparation and reduce
preparation costs.


     We also considered the following disadvantages of the merger of each
partnership:



                                      -7-
   18


o    Limited partners of each partnership will own stock in a corporation which
     is a different investment objective from investing in a partnership
     designed to generate recurring cash distributions.



o    Limited partners who become Pioneer Parent stockholders will no longer
     receive partnership cash distributions.



o    Pioneer Parent will engage in the acquisition, exploration and development
     of new oil and gas properties which will expose limited partners of each
     partnership to all of the attendant risks associated with such activities.
     Each partnership owns producing properties and does not conduct drilling
     activities. Pioneer Parent's activities may, therefore, involve greater
     risks than the activities of each partnership, but also offer the potential
     for additional benefits if the acquisition and exploitation activities are
     successful.



o    Increases in prices for oil and gas may have a more direct effect on
     limited partners of each partnership due to the immediate effect on
     potential cash distributions. However, we believe that an increase in oil
     and gas prices will also have an indirect beneficial effect on the market
     price for Pioneer Parent common stock.



o    Limited partners who become Pioneer Parent stockholders will be subject to
     the volatility of the market value of Pioneer Parent common stock. Market
     factors that may affect the common stock price will include factors other
     than those that affect the value of a limited partner's interest in a
     partnership, such as general market conditions.



o    Limited partners who become Pioneer Parent stockholders may have to
     recognize a taxable gain on the transaction.


                                FRACTIONAL SHARES


     Pioneer Parent will not issue fractional shares to any limited partner upon
completion of the merger of any partnership. Instead, Pioneer Parent will round
any fractional shares of Pioneer Parent common stock up to the nearest whole
share.




                       RECOMMENDATION TO LIMITED PARTNERS
                                  (SEE PAGE 32)



     On           , 2001, our board of directors unanimously determined that the
merger of each partnership in which you own an interest is advisable, fair to
you, as an unaffiliated limited partner, and in your best interests. Our board
recommends that you, as an unaffiliated limited partner, vote for the merger
proposals for each partnership in which you own an interest. Although our board
of directors has attempted to fulfill its fiduciary duties to you, our board of
directors had conflicting interests in evaluating each merger because each
member of our board of directors is also an officer of Pioneer Parent.


                                    FAIRNESS

     In deciding to approve the merger of each partnership on                ,
2001, our board of directors decided that each merger of a partnership in which
you own an interest is advisable, fair to you, as an unaffiliated limited
partner, and in your best interests based on a variety of factors. These factors
include:

o    the form and amount of consideration offered to you;


o    the comparison of the amount of Pioneer Parent common stock offered in each
     merger to the future cash distributions otherwise expected as oil and gas
     production continues to decline and general and administrative expenses
     continue to be incurred;


o    the elimination after the merger of each participating partnership of its
     limited partners' tax preparation costs relating to partnership tax
     information;


o    the belief that the price offered by Pioneer Parent is a competitive price
     because of:


     -    the commodity pricing used in determining the merger value for each
          partnership;

     -    Pioneer USA's position as operator of most of each partnership's
          wells; and

     -    Pioneer USA's significant ownership of nearby properties; and

o    the fairness opinion from Stanger.


                      FAIRNESS OPINION OF FINANCIAL ADVISOR
                                  (SEE PAGE 33)



     Stanger has issued a fairness opinion dated        , 2001, that, subject
to the qualifications expressed in the opinion, the merger value for each
partnership and the allocation of the merger value of the partnership (1) to the
limited partners of the partnership as a group, (2) to the general partners of
the partnership as a group, (3) to Pioneer USA as the managing or sole general
partner of the partnership, (4) to the unaffiliated limited partners of the
partnership as a group and (5) to the unaffiliated limited partners of the
nonmanaging general partner, if any, of the partnership as a group, is fair to
the unaffiliated limited partners of the partnership and the unaffiliated
limited partners of the nonmanaging general partner, if any, of the partnership,
from a financial point of view. The full text of the form of written opinion of
Stanger is attached to this document as Appendix D. You should read all of it
carefully. THE OPINION OF STANGER IS DIRECTED TO OUR BOARD OF DIRECTORS. IT IS
NOT A RECOMMENDATION TO YOU ABOUT HOW YOU SHOULD VOTE ON MATTERS RELATING TO THE
PROPOSED MERGER OF ANY PARTNERSHIP IN WHICH YOU OWN AN INTEREST.



                          MATERIAL U.S. FEDERAL INCOME
                                TAX CONSEQUENCES
                                  (SEE PAGE 48)



     You will generally recognize gain or loss equal to the difference between
(1) the value of the Pioneer



                                      -8-
   19



Parent common stock you receive in the merger of each partnership in which you
own interests and (2) your adjusted tax basis in your partnership interests in
that participating partnership. Your gain or loss will be capital or ordinary
depending on the nature of the assets held by each participating partnership in
which you own an interest and the amount of depletion and intangible drilling
and development costs that must be recaptured. You must calculate your ordinary
and capital gain or loss separately for each partnership in which you own an
interest.



     TAX MATTERS ARE VERY COMPLICATED. THE TAX CONSEQUENCES TO YOU OF EACH
MERGER OF A PARTNERSHIP IN WHICH YOU OWN AN INTEREST WILL DEPEND ON THE FACTS OF
YOUR OWN SITUATION. YOU SHOULD SEEK TAX ADVICE FOR A FULL UNDERSTANDING OF THE
PARTICULAR TAX CONSEQUENCES OF EACH SUCH MERGER TO YOU.


                       CERTIFICATION OF NON-FOREIGN STATUS


     YOUR CERTIFICATE THAT YOU ARE NOT A FOREIGN PERSON, WHICH WE CALL A
CERTIFICATION OF NON-FOREIGN STATUS, IS IMPORTANT. Whether or not you plan to
vote on the merger of each partnership in which you own an interest, please take
the time to complete and return to us the enclosed certification of non-foreign
status. If we receive a properly completed certification of non-foreign status
from you, we will not withhold federal income taxes on the Pioneer Parent common
stock to be issued to you upon the merger of each partnership in which you own
an interest.



     If we, on behalf of a partnership, are required to withhold federal income
taxes from the Pioneer Parent common stock to be issued to you upon the merger
of each partnership in which you own an interest, we will be entitled to deduct
and withhold such taxes from the Pioneer Parent common stock otherwise payable
to you. If amounts are withheld, we may, in our sole discretion:



o    sell any Pioneer Parent common stock withheld from you and use the sale
     proceeds to pay the required withholding taxes;



o    hold any Pioneer Parent common stock withheld from you as security until
     you satisfy the required withholding taxes, at which time the withheld
     Pioneer Parent common stock will be released to you; or



o    take such other reasonable action, at your expense, as is required or
     appropriate to satisfy the required withholding taxes.



Any amounts withheld as described above shall be treated as having been paid to
you.


                            RECORD DATE; VOTING POWER

     You may vote at the special meeting for each partnership in which you own
an interest if you owned partnership interests as of the close of business on ,
2001. We call this date the record date. For each partnership in which you own a
partnership interest, you may cast one vote representing your percentage of
partnership interests in that partnership. The percentage of partnership
interests that you own is determined by comparing the amount of:

o    your, or your predecessor's, initial investment, including any additional
     assessments, in the partnership; to

o    the total investment of all partners, including any additional assessments,
     in the partnership.

     YOUR VOTE IS IMPORTANT. Whether or not you plan to attend the special
meeting for each partnership in which you own an interest, please take the time
to vote by completing and mailing to us the enclosed proxy card. This will not
prevent you from revoking your proxy at any time prior to the special meeting
for each partnership in which you own an interest or from voting your
partnership interests in person if you later choose to attend the special
meeting for each partnership in which you own an interest.

                  PARTNER VOTE REQUIRED TO APPROVE THE MERGERS

     The favorable vote of the holders of a majority of the limited partnership
interests in a partnership is required to approve the merger proposals for that
partnership, except that Parker & Parsley 91-A, L.P. and Parker & Parsley 91-B,
L.P. each require the favorable vote of the holders, other than Pioneer USA, of
66-2/3% of its limited partnership interests to approve the merger proposals.


     We are generally entitled under the partnership agreements to vote
partnership interests we hold as limited partners at the special meeting for
each partnership in which we hold an interest. See "The Special Meetings --
Record Date; Voting Rights and Proxies" on page 58 of this document. We plan to
vote all our partnership interests for the merger proposals. The voting interest
that we hold in each partnership is found in Table 6 of Appendix A.



     Except as set forth above and in "Ownership of Partnership Interests" on
page 64 of this document, none of Pioneer Parent, Pioneer USA, or, to the
knowledge of Pioneer USA, any of their directors or executive officers, or any
associate or subsidiary of Pioneer Parent, Pioneer USA or any such director or
officer, beneficially owns any partnership interests of any partnership or is
otherwise entitled to vote any partnership interests.


     If limited partners of a partnership approve the merger agreement, but do
not approve the merger amendment, or vice versa, the partnership will not be
able to merge. LIMITED PARTNERS WHO WANT THEIR PARTNERSHIP TO PARTICIPATE IN THE
MERGER SHOULD VOTE FOR EACH OF THE MERGER PROPOSALS.


                            CONDITIONS TO EACH MERGER
                                  (SEE PAGE 55)


     We will complete the merger of each partnership only if the conditions of
the merger agreement are satisfied or, if permitted, waived. These conditions
include:


                                      -9-
   20


o    the limited partners' adoption and approval of the merger proposals;

o    the absence of any law or court order that prohibits the merger; and

o    the absence of any lawsuit challenging the legality or any aspect of the
     merger.


     So long as the law allows us to do so, Pioneer Parent and we may choose to
complete a merger of any partnership even though a condition has not been
satisfied if the limited partners have approved the merger proposals. Pioneer
Parent and we may complete the merger of any one or some of the partnerships for
which the listed conditions have been satisfied, even if limited partners in
other partnerships do not approve the merger proposals.



                   TERMINATION OF THE MERGER OF A PARTNERSHIP
                                  (SEE PAGE 56)



     Pioneer Parent and Pioneer USA may jointly terminate the merger agreement,
for any or all of the partnerships, at any time, even after limited partner
approval. Either Pioneer Parent or Pioneer USA may terminate the merger
agreement for any or all of the partnerships in some circumstances, including
the following:


o    the limited partners of a partnership fail to approve that partnership's
     merger; or

o    if any of the other parties is in material breach of the merger agreement.


In addition, (1) Pioneer USA may terminate the merger agreement for any
partnership, if Pioneer USA determines that termination of the merger agreement
is required for its board of directors to comply with its fiduciary duties and
(2) Pioneer Parent may abandon the proposed merger of any or all of the
partnerships at any time prior to the special meeting for any such partnership
for any reason including changes in, among other things, the price of Pioneer
Parent common stock, the market prices for oil and gas generally or the oil and
gas industry generally.



                   EFFECT OF DEBT OWED BY A LIMITED PARTNER TO
                            PIONEER USA ON AMOUNT OF
                   PIONEER PARENT COMMON STOCK TO BE RECEIVED
                             BY THE LIMITED PARTNER



     If a limited partner is indebted to Pioneer USA for any portion of the
limited partner's original investment in the partnership, Pioneer USA plans to
apply the Pioneer Parent common stock that would otherwise be distributed to the
limited partner upon completion of the merger of the partnership against that
limited partner's indebtedness. If a limited partner's indebtedness to Pioneer
USA is less than the merger value allocated to limited partnership interests
held by the limited partner, the limited partner will receive Pioneer Parent
common stock equal to the amount by which such merger value exceeds such
indebtedness. If a limited partner's indebtedness to Pioneer USA is greater than
the merger value allocated to the limited partnership interests held by the
limited partner, Pioneer USA may collect the deficiency from the limited
partner.


                     EFFECTS OF THE MERGER OF A PARTNERSHIP
                     ON ITS LIMITED PARTNERS WHO DO NOT VOTE
                             IN FAVOR OF THE MERGER


     You will be bound by the merger of a partnership in which you own interests
if the limited partners in your partnership vote a majority, or 66-2/3% for
Parker & Parsley 91-A, L.P. and Parker & Parsley 91-B, L.P., of their
partnership interests in favor of the merger, even if you vote against the
merger. If the merger of your partnership occurs, you will be entitled to
receive only an amount of Pioneer Parent common stock based on the merger value
for your partnership interests. You will not have appraisal, dissenters' or
similar rights in connection with the merger, even if you vote against the
merger.



                      FUTURE OF A PARTNERSHIP THAT DOES NOT
                            PARTICIPATE IN THE MERGER
                                  (SEE PAGE 51)



     If your partnership does not participate in the merger of that partnership
for any reason, that partnership will remain in existence. Some reasons your
partnership might not participate in the merger are (1) that the limited
partners vote against the merger, (2) that a condition in the merger agreement
is not satisfied, or (3) that Pioneer Parent or we exercise a termination right
with respect to the merger for that partnership.



     At about the same time that we mail certificates representing shares of
Pioneer Parent common stock to the partners of each participating partnership in
payment of the merger value for that partnership, we will mail any cash
distributions that were delayed for administrative purposes prior to the
completion of the merger of each participating partnership to the partners of
each nonparticipating partnership.


     We have not formulated an alternative business plan for any
nonparticipating partnership. The business objectives of each nonparticipating
partnership will continue as they are. We plan to continue to manage each
nonparticipating partnership and operate it in accordance with the terms of its
current partnership agreement. Each nonparticipating partnership will continue
to operate as a separate legal entity with its own assets and liabilities.
Distributions from any nonparticipating partnership are expected to continue to
decline since its production revenues are expected to continue to decline more
quickly than its production costs. Regardless of whether any nonparticipating
partnership distributes cash, limited partners must continue to include their
share of partnership income and loss in their individual tax returns.


     The board of directors of each of Pioneer Parent and Pioneer USA will
decide what, if any, actions Pioneer Parent or Pioneer USA, respectively, will
take regarding any nonparticipating partnership. Potential activities might
include a tender offer for partnership interests of limited partners or a
proposal to acquire



                                      -10-
   21


the assets of, or merge with, one or more of the nonparticipating partnerships.
The proposal may be on terms similar to or different from those of the mergers
described in this document.

                                EXPENSES AND FEES


     The expenses and fees to be incurred in connection with the merger of each
partnership are expected to be approximately $2.0 million in total. Each
participating partnership will pay its pro rata share, based on its reserve
value, of those estimated expenses and fees. Each nonparticipating partnership
will pay a portion of the estimated expenses and fees of the mergers otherwise
allocable to the partnership based on a fraction, the numerator of which is the
percentage of the partnership's limited partnership interests that are voted in
favor of the merger proposals and the denominator of which is the percentage of
the partnership's limited partnership interests for which votes are cast.
Pioneer Parent has agreed to pay (1) the remainder of the estimated expenses and
fees otherwise allocable to such nonparticipating partnership, (2) any expenses
and fees actually incurred in excess of $2.0 million, and (3) if Pioneer Parent
terminates or abandons the merger as to any partnership, any expenses or fees
allocated to that partnership. Pioneer Parent and Pioneer USA have reduced each
partnership's merger value by that partnership's pro rata share of the estimated
expenses and fees.


                               REGULATORY APPROVAL


     No federal or state regulatory requirements must be satisfied or approvals
obtained in connection with the merger of any of the partnerships as described
in this document, except (1) filing a registration statement that includes this
document with the SEC and obtaining the SEC's declaration that the registration
statement is effective under the Securities Act of 1933, and (2) filing
certificates of merger with the Secretary of State of the State of Delaware and
the Secretary of the State of the State of Texas.


                              SIMILAR TRANSACTIONS


     During March 2001, Pioneer Parent offered to acquire all of the direct oil
and gas interests owned by some former officers and employees of Pioneer Parent
and Pioneer USA in properties in which Pioneer Parent and Pioneer USA own
interests. The merger value for the direct oil and gas interests was equal to
the present value of estimated future net revenues from the oil and gas reserves
attributable to the interests, as of March 31, 2001. In determining the present
value, Pioneer Parent and Pioneer USA used (1) a five-year NYMEX futures price
for oil and gas as of March 19, 2001 with prices held constant after year five
at the year five price, less standard industry adjustments, (2) historical
operating costs adjusted only for those items affected by commodity prices, such
as production taxes and ad valorem taxes, and (3) a 13.5% discount rate. The
consideration offered in the purchases of the direct oil and gas interests was
all cash since offering and registering Pioneer Parent common stock in those
purchases was cost-prohibitive due to the small size of such transactions.



     Additionally, in December 2000, Pioneer Parent received the approval of the
partners of 13 employee limited partnerships to merge with Pioneer USA for total
merger consideration of $2.0 million. Of the total merger consideration, $0.3
million was paid to current Pioneer Parent employees. The merger value of each
employee partnership was equal to the sum of the present value of estimated
future net revenues from the partnership's estimated oil and gas reserves and
its net working capital, in each case as of September 30, 2000, less the cash
distributions on October 15, 2000 and November 15, 2000, by that partnership to
its partners. In determining the present value, Pioneer Parent and Pioneer USA
used (1) a five-year NYMEX futures price for oil and gas as of August 25, 2000
with prices held constant after year five at the year five price, less standard
industry adjustments, (2) historical operating costs adjusted only for those
items affected by commodity prices, such as production taxes and ad valorem
taxes, and (3) a 13.5% discount rate. The consideration paid in the mergers of
the employee limited partnerships was all cash. Using the same parameters as
described above, Pioneer Parent purchased all of the direct oil and gas
interests held by Scott D. Sheffield, its chairman of the board of directors and
chief executive officer, for $0.2 million during October 2000. As with the
purchases of the direct oil and gas interests described above, offering and
registering Pioneer Parent common stock in those mergers was cost-prohibitive
due to the small size of such transactions.



                               THIRD PARTY OFFERS
                                  (SEE PAGE 52)



     We will consider any offers from third parties to purchase any partnership
or its assets. Those who wish to make an offer for any partnership or its assets
must demonstrate to our reasonable satisfaction their financial ability and
willingness to complete such a transaction. Before reviewing non-public
information about a partnership, a third party will need to enter into a
customary confidentiality agreement. Offers should be at prices and on terms
that are fair to the partners of the partnership and more favorable to the
unaffiliated limited partners than the prices and terms proposed in the merger
for that partnership described in this document. Pioneer Parent has the right to
match or top any such offer. In addition, any such offer would be subject to our
right to continue operation of the properties. Since first announcing our
willingness to consider third party offers in September 1999, we have not
received any third party offer for any partnership or its assets.



                       COMPARATIVE PER SHARE MARKET PRICE
                            INFORMATION (SEE PAGE 62)



     On April 16, 2001, the last full trading day before the public announcement
of the proposed merger of each partnership, Pioneer Parent common stock closed
at $17.27 per share. On        , 2001, Pioneer Parent common stock closed at
$   per share.


     No liquid market exists for interests in any of the partnerships. See Table
15 of Appendix A for historical information about recent trades per $1,000


                                      -11-
   22


initial limited partner investment in each partnership and Table 7 of Appendix A
for the average historical quarterly cash distributions per $1,000 initial
limited partner investment for each partnership.


                                      -12-
   23


        SUMMARY HISTORICAL CONSOLIDATED FINANCIAL DATA OF PIONEER PARENT


     The following table sets forth summary financial information of Pioneer
Parent for the three months ended March 31, 2001 and 2000 and each of the five
years in the period ended December 31, 2000. This financial information was
derived from the consolidated financial statements of Pioneer Parent. This data
should be read in conjunction with the consolidated financial statements of
Pioneer Parent and Management's Discussion and Analysis of Financial Condition
and Results of Operations contained in the reports incorporated by reference in
this document.





                                            THREE MONTHS ENDED
                                                 MARCH 31,                              YEAR ENDED DECEMBER 31,
                                           ----------------------    -------------------------------------------------------------
                                              2001        2000          2000         1999         1998        1997(a)       1996
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
                                                 (UNAUDITED)
                                                                   (IN MILLIONS EXCEPT PER SHARE DATA)
                                                                                                  
STATEMENT OF OPERATIONS DATA:
  Revenues:
   Oil and gas ........................... $   258.0    $   174.4    $   852.7    $   644.6    $   711.5    $   536.8    $   396.9
   Natural gas processing ................        --           --           --           --           --           --         23.8
   Interest and other (b) ................       5.1          3.7         25.8         89.7         10.4          4.3         17.5
   Gain (loss) on disposition of
    assets, net ..........................       7.3          8.4         34.2        (24.2)         (.4)         4.9         97.1
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
                                               270.4        186.5        912.7        710.1        721.5        546.0        535.3
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
  Costs and expenses:
   Oil and gas production ................      55.8         43.1        189.3        159.5        223.5        144.2        110.3
   Natural gas processing ................        --           --           --           --           --           --         12.5
   Depletion, depreciation and
    amortization .........................      52.2         51.9        214.9        236.1        337.3        212.4        112.1
   Impairment of properties and
    facilities ...........................        --           --           --         17.9        459.5      1,356.4           --
   Exploration and abandonments ..........      22.9         13.1         87.5         66.0        121.9         77.2         23.0
   General and administrative ............      10.4          9.7         33.3         40.2         73.0         48.8         28.4
   Reorganization ........................        --           --           --          8.5         33.2           --           --
   Interest ..............................      35.6         39.8        162.0        170.3        164.3         77.5         46.2
   Other(c) ..............................      25.2         14.4         67.2         34.7         39.6          7.1          2.5
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
                                               202.1        172.0        754.2        733.2      1,452.3      1,923.6        335.0
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
  Income (loss) before income taxes
   and extraordinary item ................      68.3         14.5        158.5        (23.1)      (730.8)    (1,377.6)       200.3
  Income tax benefit (provision) .........       (.4)          .3          6.0           .6        (15.6)       500.3        (60.1)
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
  Income (loss) before extraordinary
   item ..................................      67.9         14.8        164.5        (22.5)      (746.4)      (877.3)       140.2
  Extraordinary item .....................        --           --        (12.3)          --           --        (13.4)          --
                                           ---------    ---------    ---------    ---------    ---------    ---------    ---------
  Net income (loss) ...................... $    67.9    $    14.8    $   152.2    $   (22.5)   $  (746.4)   $  (890.7)   $   140.2
                                           =========    =========    =========    =========    =========    =========    =========
  Income (loss) before extraordinary
   item per share:
    Basic ................................ $     .69    $     .15    $    1.65    $    (.22)   $   (7.46)   $  (16.88)   $    3.95
                                           =========    =========    =========    =========    =========    =========    =========
    Diluted .............................. $     .68    $     .15    $    1.65    $    (.22)   $   (7.46)   $  (16.88)   $    3.47
                                           =========    =========    =========    =========    =========    =========    =========
  Net income (loss) per share:
    Basic ................................ $     .69    $     .15    $    1.53    $    (.22)   $   (7.46)   $  (17.14)   $    3.95
                                           =========    =========    =========    =========    =========    =========    =========
    Diluted .............................. $     .68    $     .15    $    1.53    $    (.22)   $   (7.46)   $  (17.14)   $    3.47
                                           =========    =========    =========    =========    =========    =========    =========
  Dividends per share ....................        --    $      --    $      --    $      --    $     .10    $     .10    $     .10
                                           =========    =========    =========    =========    =========    =========    =========
  Weighted average basic shares
   outstanding ...........................      98.4        100.2         99.4        100.3        100.1         52.0         35.5


STATEMENT OF CASH FLOWS DATA:
  Cash flows from operating activities ... $   131.7    $    47.2    $   430.1    $   255.2    $   314.1    $   228.2    $   230.1
  Cash flows from (used in) investing
     activities .......................... $   (88.8)   $   (39.9)   $  (194.5)   $   199.0    $  (517.0)   $  (341.2)   $    13.7
  Cash flows from (used in) financing
     activities .......................... $   (50.5)   $    (8.9)   $  (244.1)   $  (479.1)   $   190.9    $   166.0    $  (245.4)

BALANCE SHEET DATA (AS OF DECEMBER 31):
  Working capital (deficit)(d) ........... $  (153.1)   $     3.1    $   (25.1)   $   (13.7)   $  (324.8)   $    46.6    $    26.1
  Property, plant and equipment, net ..... $ 2,557.1    $ 2,511.3    $ 2,515.0    $ 2,503.0    $ 3,034.1    $ 3,515.8    $ 1,040.4
  Total assets ........................... $ 2,922.2    $ 2,969.9    $ 2,954.4    $ 2,929.5    $ 3,481.3    $ 4,153.0    $ 1,199.9
  Long-term obligations .................. $ 1,744.8    $ 1,913.8    $ 1,804.5    $ 1,914.5    $ 2,101.2    $ 2,124.0    $   329.0
  Preferred stock of subsidiary .......... $      --    $      --    $      --    $      --    $      --    $      --    $   188.8
  Total stockholders' equity(e) .......... $   841.0    $   816.6    $   904.9    $   774.6    $   789.1    $ 1,548.8    $   530.3



                                      -13-
   24


----------

(a)  Includes amounts relating to the acquisition of MESA Inc. and Chauvco
     Resources Ltd. in August and December 1997, respectively.

(b)  1999 includes $41.8 million of option fees and liquidated damages related
     to an unsuccessful asset sale and $30.2 million of income associated with
     an excise tax refund.


(c)  The three month periods ended March 31, 2001 and 2000 and the years ended
     December 31, 2000, 1999, 1998 and 1997 include non-cash mark-to-market
     charges for changes in the fair values of non-hedge financial instruments
     of $8.8 million, $13.5 million, $58.5 million, $27.0 million, $21.2 million
     and $5.2 million, respectively.



(d)  The working capital deficit for the three month period ended March 31, 2001
     included $101.5 million of net derivative obligations. The 1998 working
     capital deficit includes $306.5 million of current maturities of long-term
     debt.



(e)  On January 1, 2001, Pioneer Parent adopted the provisions of Statement of
     Financial Accounting Standards No. 133, "Accounting for Derivative
     Instruments and Hedging Activities." In accordance with those provisions,
     Pioneer Parent recognized a transition adjustment which significantly
     reduced stockholders' equity. As of March 31, 2001, deferred hedge gains
     and losses have reduced Pioneer Parent's stockholders' equity by $110.5
     million.




                                      -14-
   25


      SUMMARY UNAUDITED PRO FORMA COMBINED FINANCIAL DATA OF PIONEER PARENT



     The following table sets forth summary unaudited pro forma combined
financial data of Pioneer Parent that is presented to give effect to the merger
of each of the partnerships. The information was prepared based on the following
assumptions:


     o    The merger of each partnership will be accounted for as a purchase
          business combination under generally accepted accounting principles.

     o    The income statement data is presented as if the merger of each
          partnership had been consummated on January 1, 2000.


     o    The balance sheet data is presented as if the merger of each
          partnership had been consummated on March 31, 2001.


     You should consider the following:


     o    The unaudited pro forma combined financial data are not necessarily
          indicative of the results of operations or the financial position of
          Pioneer Parent that would have occurred had the merger of each
          partnership in which you own an interest been consummated on January
          1, 2000, nor are they necessarily indicative of future results of
          operations or financial position of Pioneer Parent.



     o    The unaudited pro forma combined revenue and expense data exclude the
          cost savings expected to be realized through the consolidation of
          operations of Pioneer Parent and each partnership and the elimination
          of duplicate expenses.



     The unaudited pro forma combined financial statements should be read
together with (1) the historical consolidated financial statements of Pioneer
Parent incorporated by reference in this document, (2) the historical financial
statements of each partnership contained in the supplement to this document for
the partnership, and (3) the unaudited pro forma combined financial statements
contained elsewhere in this document. With respect to future cash distributions,
see "Questions and Answers About the Merger of Each Partnership -- What Happens
to My Future Cash Distributions?" See also "Where You Can Find More Information"
on the inside front cover page of this document.





                                                                             PRO FORMA           PRO FORMA
                                                                         THREE MONTHS ENDED      YEAR ENDED
                                                                           MARCH 31, 2001    DECEMBER 31, 2000
                                                                           --------------    -----------------
                                                                         (IN THOUSANDS EXCEPT PER SHARE DATA)
                                                                                        
STATEMENTS OF OPERATIONS:
     Revenues:
         Oil and gas ..............................................        $   270,754         $   901,382
         Interest and other .......................................              5,261              26,231
         Gain on disposition of assets, net .......................              7,368              34,425
                                                                           -----------         -----------
                                                                               283,383             962,038
                                                                           -----------         -----------
     Costs and Expenses:
         Oil and gas production ...................................             59,533             202,176
         Depletion, depreciation and amortization .................             53,754             221,942
         Exploration and abandonments .............................             22,924              87,619
         General and administrative ...............................             12,282              40,406
         Interest .................................................             35,616             161,952
         Other ....................................................             25,217              67,231
                                                                           -----------         -----------
                                                                               209,326             781,326
                                                                           -----------         -----------
     Income from continuing operations before income taxes ........             74,057             180,712
     Income tax benefit (provision) ...............................               (400)              6,000
                                                                           -----------         -----------
     Income from continuing operations ............................        $    73,657         $   186,712
                                                                           ===========         ===========
     Income from continuing operations per common share, basic ....        $       .71         $      1.77
     Income from continuing operations per common share,
         diluted ..................................................        $       .70         $      1.77
     Weighted average number of shares outstanding, basic .........            104,235             105,234
     Weighted average number of shares outstanding, diluted .......            105,564             105,618
BALANCE SHEET DATA (AT PERIOD END)
     Property, plant and equipment, net ...........................        $ 2,658,004
     Total assets .................................................        $ 3,029,547
     Long-term debt ...............................................        $ 1,550,230
     Stockholders' equity .........................................        $   946,376




                                      -15-
   26


                     SUMMARY OIL AND GAS RESERVE INFORMATION


     The following table sets forth summary information on Pioneer Parent's and
the combined partnerships' proved oil and gas reserves at December 31, 2000, and
the summary pro forma combined information of Pioneer Parent on proved oil and
gas reserves assuming the merger of each partnership had taken place on December
31, 2000. Pioneer Parent's and the combined partnerships' historical and Pioneer
Parent's pro forma combined proved oil and gas reserve information set forth
below and incorporated by reference in this document are only estimates based
primarily on reports prepared by Pioneer Parent's engineers for Pioneer Parent's
proved reserves and independent petroleum engineers for the combined
partnerships' proved reserves as of December 31, 2000. The reserve information
as of December 31, 2000 is based on the prices of oil and gas as of that time.
The discounted future net cash flows set forth or incorporated by reference in
this document should not be considered as the current market value of the
estimated oil and gas reserves attributable to Pioneer Parent's, the combined
partnerships' or any partnership's properties. Under the applicable requirements
of the Securities and Exchange Commission, the estimated discounted future net
cash flows from proved reserves are based on prices and costs as of the date of
the estimate, while actual future prices and costs may be materially higher or
lower.


        SUMMARY HISTORICAL AND PRO FORMA OIL AND GAS RESERVE INFORMATION
                              AT DECEMBER 31, 2000




                                                                        OIL AND       NATURAL    BARRELS OF
                                                                          NGLS          GAS      EQUIVALENTS
                                                                        (MMBbls)       (Bcf)       (MMBOE)
                                                                        ---------    ---------   ----------
                                                                                         
NET PROVED RESERVES (HISTORICAL):
PIONEER PARENT:
   Developed .......................................................        232.5      1,507.8        483.8
   Undeveloped .....................................................         79.8        387.7        144.4
                                                                        ---------    ---------    ---------
     Total .........................................................        312.3      1,895.5        628.2
                                                                        =========    =========    =========
COMBINED PARTNERSHIPS:
   Developed .......................................................         27.3         37.6         33.6
                                                                        =========    =========    =========

NET PROVED RESERVES (PRO FORMA COMBINED):
   Developed .......................................................        261.8      1,546.8        519.6
   Undeveloped .....................................................         79.8        387.7        144.4
                                                                        ---------    ---------    ---------
     Total .........................................................        341.6      1,934.5        664.0
                                                                        =========    =========    =========

RESERVE VALUATION INFORMATION (IN MILLIONS):
PIONEER PARENT:
   Estimated future net cash flows .................................                              $  10,864
   Standardized measure of discounted future net cash flows ........                              $   5,646
COMBINED PARTNERSHIPS:
   Estimated future net cash flows .................................                              $     423
   Standardized measure of discounted future net cash flows(1) .....                              $     207
PRO FORMA COMBINED:
   Estimated future net cash flows .................................                              $  11,267
   Standardized measure of discounted future net cash flows ........                              $   5,838



---------

(1)  The combined partnerships do not reflect a federal income tax provision
     since the partners of each partnership include the income of the
     partnership in their respective individual federal income tax returns.


                                      -16-
   27

                           COMPARATIVE PER SHARE DATA


     The following table summarizes the per share information for Pioneer Parent
and the per $1,000 limited partner investment for the combined partnerships on a
historical, equivalent pro forma combined and pro forma combined basis. The pro
forma information gives effect to the merger of each partnership accounted for
by Pioneer Parent as a purchase business combination. You should read this
information together with the historical financial statements (1) included in
the annual reports on Form 10-K and other information that Pioneer Parent has
filed with the Securities and Exchange Commission and (2) included in the
supplement to this document for each partnership. See "Where You Can Find More
Information" on the inside front cover page of this document. With respect to
future cash distributions, see "Questions and Answers About the Merger of Each
Partnership -- What Happens to My Future Cash Distributions?" and "Risk Factors
-- Pioneer Parent Might Not Declare Dividends." You should not rely on the pro
forma combined information as being indicative of the results that would have
occurred had the merger of each partnership been completed on January 1, 2000,
or the future results that Pioneer Parent will experience after the merger of
each partnership. In addition, because Pioneer Parent has both a different legal
structure and purpose from each partnership, the information about Pioneer
Parent and the information about the combined partnerships are not necessarily
comparable.





                                                                            THREE MONTHS ENDED       YEAR ENDED
                                                                              MARCH 31, 2001      DECEMBER 31, 2000
                                                                            ------------------    -----------------
                                                                                            
HISTORICAL -- PIONEER PARENT:
     Income from continuing operations per share:
         Basic ...........................................................        $   .69              $  1.65
         Diluted .........................................................            .68                 1.65
     Book value per share ................................................           8.56                 9.19
     Cash dividends per common share .....................................           0.00                 0.00
HISTORICAL -- COMBINED PARTNERSHIPS:
     Income per $1,000 limited partner investment ........................        $ 14.84              $ 55.15
     Book value per $1,000 limited partner investment ....................         120.50               124.45
     Cash distributions per $1,000 limited partner investment ............          18.79                57.22
EQUIVALENT PRO FORMA COMBINED PARTNERSHIPS PER $1,000 LIMITED PARTNER
INVESTMENT ON AN EQUIVALENT PER SHARE BASIS(1):
     Income per $1,000 limited partner investment:
         Basic ...........................................................        $  9.02              $ 22.50
         Diluted .........................................................           8.90                22.50
     Book value per $1,000 limited partner investment ....................         115.53
PRO FORMA COMBINED -- PIONEER PARENT:
     Income from continuing operations per share:
         Basic ...........................................................        $   .71              $  1.77
         Diluted .........................................................            .70                 1.77
     Book value per share ................................................           9.09




---------
(1)  Represents the "Historical -- Combined Partnerships" amounts multiplied by
     12.71, which represents the weighted average number shares of Pioneer
     Parent common stock to be received per $1,000 limited partner investment.




                                      -17-
   28
                                  RISK FACTORS

     You should carefully consider the following risk factors in determining
whether to vote to approve the merger proposals for each partnership in which
you own interests.

             RISK FACTORS RELATING TO THE MERGER OF EACH PARTNERSHIP


THE MERGER VALUE FOR EACH PARTNERSHIP INVOLVES ESTIMATES THAT MAY VARY
MATERIALLY FROM THE QUANTITIES OF OIL AND GAS ACTUALLY RECOVERED, AND
CONSEQUENTLY FUTURE NET REVENUES



     The calculations of each partnership's estimated reserves of crude oil,
natural gas liquids and natural gas and future net revenues from those reserves
included in this document are only estimates. Actual prices, production,
operating expenses and quantities of recoverable oil and natural gas reserves
may vary from those assumed in the estimates. Any significant variance from the
assumptions used could result in the actual quantity of each partnership's
reserves and future net revenues being materially different from the estimates
used in the calculation of the merger value for that partnership.



THE MERGER VALUE FOR A PARTNERSHIP WILL NOT BE ADJUSTED FOR CHANGES IN OIL AND
GAS PRICES BEFORE THE COMPLETION OF ITS MERGER



     The merger value for each partnership in which you own an interest
determines the amount of Pioneer Parent common stock you will receive in the
merger of that partnership. The merger value for each partnership is equal to
the sum of the present value of estimated future net revenues from the
partnership's estimated oil and gas reserves and its net working capital, in
each case as of March 31, 2001, less its pro rata share, based on its reserve
value, of the estimated expenses and fees of the mergers of all of the
partnerships and less the cash distribution to be mailed on or about July 12,
2001, by the partnership to its partners. Although oil and gas prices have
fluctuated greatly in the recent past and may continue to do so, the merger
value for a partnership will not be adjusted as of the closing date of the
merger of that partnership to reflect any general changes in oil or gas prices,
or any other matter generally affecting the oil and gas industry, occurring
after March 31, 2001 and prior to the closing date of the merger.


THE NUMBER OF SHARES OF PIONEER PARENT COMMON STOCK THE LIMITED PARTNERS OF EACH
PARTNERSHIP WILL RECEIVE MAY DECREASE BETWEEN NOW AND THE COMPLETION OF THE
MERGER OF THE PARTNERSHIP


     The number of shares of Pioneer Parent common stock to be issued to the
limited partners of each partnership upon the merger of the partnership will be
determined by dividing the merger value assigned to the partnership by the value
of one share of Pioneer Parent common stock determined as described below. As
discussed above, the merger value for each partnership will not be changed
between now and the completion of the merger for the partnership. In addition,
for purposes of example in this document, a share of Pioneer Parent common stock
has been valued at an assumed average closing price of $18.00. However, the
value of a share of Pioneer Parent common stock will be recalculated by
computing the average closing price of the Pioneer Parent common stock, as
reported by the New York Stock Exchange, for the ten trading days ending three
business days before the initial date of the special meeting for each
partnership. This recalculated value, and not the assumed closing average
closing price of $18.00 per share of Pioneer Parent common stock used for
illustration purposes in this document and on each limited partner's proxy card,
will be used to determine the actual number of shares of Pioneer Parent common
stock to be issued in the merger of each partnership. The recalculated value may
be more or less than the assumed average closing price of $18.00 per share of
Pioneer Parent common stock. If it is more than $18.00, you will receive fewer
shares of Pioneer Parent common stock than the illustrations in this document
show. For historical and current market prices of Pioneer Parent common stock,
see "Comparative Per Share Market Price and Dividend Information" on page 62.


CURRENT MARKET PRICES FOR OIL AND GAS MAY BE HIGHER THAN THE MERGER VALUE FOR A
PARTNERSHIP, WHICH MAY AFFECT DELIVERABILITY OF THE FAIRNESS OPINION


     Oil and gas prices have fluctuated greatly in the recent past and may
continue to do so in the future. Pioneer Parent calculated each merger value
based on oil and gas prices that it believes to be fair and that are supported
by current market prices. Changes in current oil and gas prices may affect the
ability of Pioneer to obtain an opinion at the time this document is mailed to
the limited partners of each partnership as to the fairness of the consideration
to be received by limited partners. If the prices used in the calculation of
each merger value significantly differ from current prices and if Pioneer Parent
does not modify its offer, the fairness opinion provider may be unable to render
its opinion.


YOU WERE NOT INDEPENDENTLY REPRESENTED IN ESTABLISHING THE TERMS OF THE MERGER
OF EACH PARTNERSHIP


     Pioneer Parent and Pioneer USA determined the terms of the merger of each
partnership, including the method for determining the merger value for that
partnership, and the type and allocation among the partners of the



                                      -18-
   29



consideration to be given in exchange for partnership interests. We did not seek
recommendations about the type of transaction or the terms or prices from any
independent underwriter, financial advisor or other securities professional
prior to accepting the consideration Pioneer Parent offered. The only
independent representatives in the mergers were Sayles, Lidji & Werbner, A
Professional Corporation, which provided legal services to Pioneer USA's board
of directors, Robert A. Stanger & Co., Inc., which will render its fairness
opinion to Pioneer USA's board of directors, and , which will render the legal
opinion required under the partnership agreement for each partnership, other
than Parker & Parsley Producing Properties 88-A, L.P. No representative group of
limited partners and no outside experts or consultants, such as investment
bankers, legal counsel, accountants or financial experts, were engaged solely to
represent the independent interests of the limited partners of any partnership
in structuring and negotiating the terms of the merger for the partnership. If
you had been separately represented, the terms of the merger for a partnership
in which you own interests might have been different and possibly more favorable
to you.



THE INTERESTS OF PIONEER PARENT, PIONEER USA AND THEIR DIRECTORS AND OFFICERS
MAY DIFFER FROM YOUR INTERESTS



     The interests of Pioneer Parent, Pioneer USA, and their directors and
officers may differ from your interests as a result of the relationships among
them. For example, Pioneer USA, as general or managing partner of each
partnership, has a duty to manage the partnership in the best interests of the
limited partners. Additionally, Pioneer USA has a duty to operate its business
for the benefit of its sole stockholder, Pioneer Parent. Also, the members of
Pioneer USA's board of directors have duties to both the limited partners of
each partnership and to Pioneer Parent. All of the members of Pioneer USA's
board of directors are officers of Pioneer Parent and have duties to Pioneer
Parent's stockholders. Pioneer USA's board of directors was aware of these
interests and considered them in approving the merger proposals for each
partnership. See "Interests of Pioneer Parent, Pioneer USA and Their Directors
and Officers" on page 63 of this document.



IT IS UNCLEAR WHAT THE MARKET DEMAND IS FOR ANY PARTNERSHIP OR ITS ASSETS OR
THAT THE TERMS OF THE MERGER OF EACH PARTNERSHIP ARE AS FAVORABLE AS COULD BE
OBTAINED IN A THIRD PARTY SALE


     In September 1999, we first announced our willingness to consider third
party offers to purchase any partnership or its assets at prices that are higher
than the 1999 merger value for the partnership, but subject to our right to
continue operation of the properties. We believe this limited form of auction
would result in a better price to the limited partners of each partnership than
if we merely offered the partnership or its assets for sale at any price. Since
that time, we have not received any third party offer for any partnership or its
assets. As a result, we cannot be sure what the market demand is for any
partnership or its assets, individually or as a whole with the other
partnerships, or what a third party would offer for any partnership. Also,
although we do not have any plans to sell or relinquish our operating rights in
any third party sale, we cannot be sure what the market demand is for any
partnership or its assets if we also sold or relinquished our operating rights.
No assurance may be given that the terms of the merger of each partnership are
as favorable as could be obtained from a sale of any partnership or its assets,
individually or as a whole with the other partnerships, to an unrelated party.


POTENTIAL LITIGATION CHALLENGING THE MERGER OF A PARTNERSHIP MAY DELAY OR BLOCK
THE MERGER AND, AS A RESULT, YOUR RECEIPT OF THE PIONEER PARENT COMMON STOCK



     One or more of the partners opposed to the merger of a partnership in which
such partner or partners own an interest may initiate legal action to stop the
merger of the partnership or to seek damages for alleged violations of federal
and state laws. Litigation challenging the merger of any partnership may delay
or block the closing of the merger for one or more of the partnerships. In
addition, if any lawsuits are filed, Pioneer Parent or Pioneer USA may decide to
terminate one or more of the mergers. If the merger of a partnership in which
you own an interest is delayed, blocked or terminated, we will delay or
terminate the issuance of the Pioneer Parent common stock that you would
otherwise receive.



REPURCHASE OFFERS IN 2001 BY EACH OF THE SIX PARTNERSHIPS WITH A REPURCHASE
OBLIGATION WERE HIGHER THAN THE MERGER VALUE FOR THE PARTNERSHIP


     The limited partners of each of the partnerships listed below may require
us to repurchase their partnership interests for cash at the times and under the
conditions described in the partnership agreements for the partnership:

         Parker & Parsley 82-I, Ltd.
         Parker & Parsley 82-II, Ltd.
         Parker & Parsley 82-III, Ltd.
         Parker & Parsley 83-A, Ltd.
         Parker & Parsley 83-B, Ltd.
         Parker & Parsley 84-A, Ltd.


     The 2001 repurchase offers were commenced and will be completed before the
date of this document. In each of the partnerships with a repurchase obligation,
the repurchase price in 2001 is higher than the price being offered



                                      -19-
   30



in the merger of the partnership. For a list of the repurchase prices in 2001
and the prior two years, see Table 8 of Appendix A. For a description of the
mechanics of the repurchase rights, see "Special Factors - Fairness Opinion -
Repurchase Offers" on page 38.



     In addition, if the limited partners of a partnership with repurchase
rights vote a majority of their partnership interests in favor of the merger of
the partnership, those repurchase rights will terminate on completion of the
merger. As a result, if the oil and gas prices used in calculating the
repurchase prices in the future were high enough to offset the additional
33-1/3% discount factor used in the repurchase calculation, the limited partners
would not have the opportunity to require Pioneer USA to repurchase the limited
partners' partnership interests for a price higher than the merger value for the
partnership.


YOU COULD BE BOUND BY THE MERGER OF EACH PARTNERSHIP IN WHICH YOU OWN AN
INTEREST EVEN IF YOU DO NOT VOTE IN FAVOR OF THE MERGER


     You will be bound by the merger of each partnership in which you own an
interest if the limited partners in the partnership vote a majority, or 66-2/3%
for Parker & Parsley 91-A, L.P. and Parker & Parsley 91-B, L.P., of their
partnership interests in favor of the merger, even if you vote against the
merger or do not vote. If the merger of the partnership occurs, you will be
entitled to receive only an amount of Pioneer Parent common stock based on the
merger value of your partnership interests in the partnership. Under the laws of
the State of Delaware and the State of Texas, which are the states of formation
of the partnerships, you are not entitled to appraisal or dissenters' rights
with respect to the merger of any partnership.



              RISKS ASSOCIATED WITH AN INVESTMENT IN PIONEER PARENT



LIMITED PARTNERS WHO BECOME PIONEER PARENT STOCKHOLDERS WILL OWN STOCK IN A
CORPORATION RATHER THAN A LIMITED PARTNERSHIP INTEREST IN A LIMITED PARTNERSHIP
RESULTING IN A FUNDAMENTAL CHANGE IN THE NATURE OF THEIR INVESTMENTS



     Limited partners of a participating partnership will become stockholders of
Pioneer Parent and will fundamentally change the nature of their investments.
Each partnership, other than Parker & Parsley 81-I, Ltd., Parker & Parsley
81-II, Ltd., Parker & Parsley 82-I, Ltd., Parker & Parsley 82-II, Ltd., Parker &
Parsley 82-III, Ltd., Parker & Parsley 83-A, Ltd., Parker & Parsley 83-B, Ltd.
and Parker & Parsley 84-A, Ltd., was formed as finite-life investment. The
partners of each partnership receive regular cash distributions out of the
partnership's net operating income and special distributions upon liquidation of
the partnership's oil and gas assets. In contrast, Pioneer Parent intends to
operate for an indefinite period of time and has no specific plans for the sale
of its investments. Because Pioneer Parent will spend a portion of its cash flow
on acquisitions, drilling and other activities, the activities of Pioneer Parent
may involve higher levels of risk than those associated with the present or
future operations of each partnership. Instead of having their investments
liquidated through the liquidation of Pioneer Parent's assets, stockholders
should expect to be able to liquidate their investment in Pioneer Parent only
through the sale of their investments in the market. The amount realized through
the sale of shares of Pioneer Parent common stock may not be equal to the amount
that would have been realized by stockholders through the sale of Pioneer
Parent's assets. Stockholders will thus be subject to the market risks of all
public companies, particularly in that the value of their equity securities may
fluctuate from time to time depending upon general market conditions, conditions
in the oil and gas industry, and Pioneer Parent's future performance. For a
description of the differences between the terms of shares of Pioneer Parent
common stock and partnership interests in each partnership, see "Comparison of
Rights of Stockholders and Partners" on page 73.



PIONEER PARENT MIGHT NOT DECLARE DIVIDENDS



     Limited partners of a participating partnership will become stockholders of
Pioneer Parent and will not receive cash distributions or will receive
distributions much smaller than the distributions received from the partnership.
Pioneer Parent's board of directors did not declare dividends to its
stockholders during 1999, 2000 or the three months ended March 31, 2001. The
determination of the amount of future cash dividends, if any, to be declared and
paid is in the sole discretion of Pioneer Parent's board of directors.



LIMITED PARTNERS WHO BECOME PIONEER PARENT STOCKHOLDERS MAY BE DILUTED



     If all partnerships participate in the mergers, the shares of Pioneer
Parent common stock to be issued will represent approximately 4.3% of the shares
of Pioneer Parent common stock outstanding on the date of this document. That
percentage is based upon the number of shares to be issued upon the merger of
each partnership using an assumed average closing price of $18.00 per share of
Pioneer Parent common stock and may increase or decrease depending on the actual
number of shares issued upon the merger of each partnership, which number will
be determined using the actual average closing price of Pioneer Parent common
stock for the ten trading days ending three business days before the initial
date of the special meeting. Because of the increased liquidity afforded to the
limited partners of each partnership after the merger of the partnership, all of
those shares of Pioneer Parent common stock may be offered for sale in a
relatively short period of time, which could result in the price at which shares
of



                                      -20-
   31



Pioneer Parent common stock trade after completion of the merger of each
partnership being less than the price at which such shares traded immediately
prior to the completion of the merger of each partnership. In addition, limited
partners of a partnership who become Pioneer Parent stockholders will be subject
to the risk that their equity interests in Pioneer Parent may be diluted through
the issuance of additional equity securities. Pioneer Parent has the right to
issue, at the discretion of its board of directors, shares other than those to
be issued in the merger of each partnership, upon such terms and conditions and
at such prices as its board of directors may establish. In addition, Pioneer
Parent may in the future issue preferred stock that might have priority over the
Pioneer Parent common stock as to distributions and liquidation proceeds.


DIVIDENDS PAID TO PIONEER PARENT STOCKHOLDERS ARE TAXED AT TWO LEVELS


     Pioneer Parent is taxed on its income, after deduction of expenses, at both
the federal and state levels. Pioneer Parent stockholders, including limited
partners who become Pioneer Parent stockholders, are separately taxed on the
receipt, if any, of dividends.



PIONEER PARENT IS AN INDEPENDENT OIL AND GAS EXPLORATION AND DEVELOPMENT COMPANY
AND ITS BUSINESS ACTIVITIES INVOLVE RISKS



     Pioneer Parent is an independent oil and gas exploration and development
company. Its purpose is to competitively and profitably explore for, develop and
produce proved oil, natural gas liquids and gas reserves. The nature of those
business activities subjects Pioneer Parent to hazards and risks, including the
following:



o    Pioneer Parent's profitability is highly dependent on the prices of oil and
     gas, which have historically been very volatile. Pioneer Parent's revenues,
     profitability, cash flow and future rate of growth are highly dependent on
     prices of oil and gas, which are affected by numerous factors beyond
     Pioneer Parent's control. Oil and gas prices historically have been very
     volatile. If the significant downward trend in oil and gas prices
     experienced in 1998, as compared to 2000 and 1999, were to resume, it would
     have a material adverse effect on Pioneer Parent's revenues, profitability
     and cash flow and could result in a reduction in the carrying value of
     Pioneer Parent's oil and gas properties and an increase in Pioneer Parent's
     deferred tax asset valuation allowance.



o    Pioneer Parent's drilling activities may not be productive. Drilling
     involves numerous risks, including the risk that no commercially productive
     gas or oil reservoirs will be encountered. The cost of drilling, completing
     and operating wells is often uncertain and drilling operations may be
     curtailed, delayed or canceled as a result of a variety of factors,
     including (1) unexpected drilling conditions, (2) pressure or
     irregularities in formations, (3) equipment failures or accidents, (4)
     adverse weather conditions and (5) shortages or delays in the delivery of
     equipment. Pioneer Parent's future drilling activities may not be
     successful and, if unsuccessful, such failure could have an adverse effect
     on Pioneer Parent's future results of operations and financial condition.
     While all drilling, whether developmental or exploratory, involves these
     risks, exploratory drilling involves greater risks of dry holes or failure
     to find commercial quantities of hydrocarbons. Because of the percentage of
     Pioneer Parent's capital budget devoted to exploratory projects, it is
     likely that Pioneer Parent will continue to experience exploration and
     abandonment expense.



o    Pioneer Parent may be required to recognize non-cash charges relating to
     unproved property costs. At December 31, 2000 and 1999, Pioneer Parent
     carried unproved property costs of $229.2 million and $257.6 million,
     respectively. United States generally accepted accounting principles
     require Pioneer Parent to periodically evaluate these costs on a
     project-by-project basis in comparison to their estimated value. These
     evaluations will be affected by (1) results of exploration activities, (2)
     commodity price outlooks, (3) planned future sales or (4) expiration of all
     or a portion of the leases, contracts and permits related to such projects.
     If the quantity of potential reserves determined by such evaluations is not
     sufficient to fully recover the cost invested in each project, Pioneer
     Parent will recognize non-cash charges in the earnings of future periods.
     During 1999 and 1998, Pioneer Parent recognized non-cash impairment
     provisions of $17.9 million and $147.3 million, respectively, to reduce the
     carrying value of its unproved properties.



o    Pioneer Parent's growth depends on its ability to acquire oil and gas
     properties on a profitable basis. Acquisitions of producing oil and gas
     properties have been a key element of Pioneer Parent's growth. Pioneer
     Parent's growth following the full development of its existing property
     base could be impeded if it is unable to acquire additional oil and gas
     properties on a profitable basis. The success of any acquisition will
     depend on a number of factors, including the ability to estimate accurately
     the recoverable volumes of reserves, rates of future production and future
     net revenues attributable to reserves and to assess possible environmental
     liabilities. All of these factors affect whether an acquisition will
     ultimately generate cash flows sufficient to provide a suitable return on
     investment. Even though Pioneer Parent performs a review of the properties
     it seeks to acquire that it believes is consistent with industry practices,
     such reviews are often limited in scope.



                                      -21-
   32


o    If Pioneer Parent is unable to dispose of non-strategic assets at
     acceptable prices this would hinder its ability to make capital resources
     available for more profitable activities. Pioneer Parent regularly reviews
     its property base for the purpose of identifying non-strategic assets, the
     disposition of which would increase capital resources available for other
     activities and create organizational and operational efficiencies. Various
     factors could materially affect the ability of Pioneer Parent to dispose of
     non-strategic assets, including the availability of purchasers willing to
     purchase the non-strategic assets at prices acceptable to Pioneer Parent.



o    The operation of natural gas processing plants involves the potential for
     damage claims. As of December 31, 2000, Pioneer Parent owns interests in
     nine natural gas processing plants and four treating facilities. Pioneer
     Parent operates six of the plants and all four treating facilities. There
     are significant risks associated with the operation of natural gas
     processing plants. Gas and natural gas liquids are volatile and explosive
     and may include carcinogens. Damage to or misoperation of a natural gas
     processing plant or facility could result in an explosion or the discharge
     of toxic gases, which could result in significant damage claims in addition
     to interrupting a revenue source.



o    Pioneer Parent is not fully insured against operating hazards. Pioneer
     Parent's operations are subject to all the risks normally incident to the
     oil and gas exploration and production business, including blowouts,
     cratering, explosions and pollution and other environmental damage, any of
     which could result in substantial losses to Pioneer Parent due to injury or
     loss of life, damage to or destruction of wells, production facilities or
     other property, clean-up responsibilities, regulatory investigations and
     penalties and suspension of operations. Although Pioneer Parent currently
     maintains insurance coverage that it considers reasonable and that is
     similar to that maintained by comparable companies in the oil and gas
     industry, it is not fully insured against certain of these risks, either
     because such insurance is not available or because of high premium costs.



o    In the event of noncompliance, liabilities under environmental laws and
     regulations could be substantial. The oil and gas business is also subject
     to environmental hazards, such as oil spills, gas leaks and ruptures and
     discharges of toxic substances or gases that could expose Pioneer Parent to
     substantial liability due to pollution and other environmental damage. A
     variety of federal, state and foreign laws and regulations govern the
     environmental aspects of the oil and gas business. Noncompliance with these
     laws and regulations may subject Pioneer Parent to penalties, damages or
     other liabilities, and compliance may increase the cost of Pioneer Parent's
     operations. Such laws and regulations may also affect the costs of
     acquisitions.



     Pioneer Parent does not believe that its environmental risks are materially
     different from those of comparable companies in the oil and gas industry.
     Nevertheless, no assurance can be given that future environmental laws will
     not result in a curtailment of production or processing or a material
     increase in the costs of production, development, exploration or processing
     or otherwise adversely affect Pioneer Parent's operations and financial
     condition. Pollution and similar environmental risks generally are not
     fully insurable.



o    There are factors outside of Pioneer Parent's control which could impair
     its ability to satisfy its debt obligations. Pioneer Parent is a borrower
     under fixed term senior notes and a line of credit. The terms of Pioneer
     Parent's borrowings under the senior notes and the line of credit specify
     scheduled debt repayments and require Pioneer Parent to comply with
     covenants and restrictions. Pioneer Parent's ability to comply with the
     debt repayment terms, associated covenants and restrictions is dependent
     on, among other things, factors outside Pioneer Parent's direct control,
     such as commodity prices, interest rates and competition for available debt
     financing.



o    The oil and gas industry is highly competitive. Pioneer Parent competes
     with other companies, producers and operators for acquisitions and in the
     exploration, development, production and marketing of oil and gas. Some of
     these competitors have substantially greater financial and other resources
     than Pioneer Parent.



o    Present or future regulations could adversely affect Pioneer Parent's
     business and operations. Pioneer Parent's business is regulated by a
     variety of federal, state, local and foreign laws and regulations. There
     can be no assurance that present or future regulations will not adversely
     affect Pioneer Parent's business and operations.



o    Pioneer Parent has international operations which are subject to
     international economic and political risks. At December 31, 2000,
     approximately 22% of Pioneer Parent's proved reserves of oil, natural gas
     liquids and gas were located outside the United States (17% in Argentina,
     4% in Canada and 1% in South Africa). The success and profitability of
     international operations may be adversely affected by risks



                                      -22-
   33



     associated with international activities, including (1) economic and labor
     conditions, (2) political instability, (3) tax laws, including United
     States taxes on foreign subsidiaries, and (4) changes in the value of the
     United States dollar versus the local currency. To the extent that Pioneer
     Parent is involved in international activities, changes in exchange rates
     may adversely affect Pioneer Parent's consolidated revenues and expenses,
     as expressed in United States dollars.



o    Numerous uncertainties exist in estimating Pioneer Parent's quantities of
     proved reserves and future net revenues. Estimates of proved reserves and
     related future net revenues are based on various assumptions which may
     prove to be inaccurate. Therefore, those estimates should not be construed
     as being accurate estimates of the current market value of Pioneer Parent's
     proved reserves.





                                      -23-
   34


                                 SPECIAL FACTORS

BACKGROUND OF THE MERGER OF EACH PARTNERSHIP

     The partnerships were formed from 1981 through 1991 under the sponsorship
of various affiliated companies collectively known as Parker & Parsley. On
February 19, 1991, Parker & Parsley's principal company converted from limited
partnership form to corporate form and acquired most of the assets of five oil
and gas limited partnerships. The new corporation was called Parker & Parsley
Petroleum Company, and it owned the sole or managing general partners of the
partnerships.


     In early 1992, Parker & Parsley Petroleum Company decided that it could not
fully realize the benefits of the properties it had acquired while continuing to
devote substantial resources to the sponsorship of and drilling for each
partnership. It stopped sponsoring oil and gas development drilling and income
partnerships and focused on its corporate development. In 1997, Parker & Parsley
Petroleum Company and MESA Inc. combined their businesses in a merger that
created Pioneer Natural Resources Company. That same year, Pioneer Parent
combined many of its U.S. subsidiaries, including the managing or sole general
partner of each of the partnerships, into its main subsidiary, Pioneer USA.



     From time to time since 1992, Pioneer Parent and its predecessors have had
general, internal discussions about whether to consolidate each partnership
pursuant to a transaction such as the merger of each partnership. On several
occasions, Pioneer Parent or its predecessors engaged outside legal counsel and
had discussions with investment banks about a possible combination with each of
the partnerships. Some of those discussions were with Stanger. The contemplated
structure of the combination has varied significantly during these internal
discussions and has included issuances of common stock, combinations of common
stock and cash, and cash-only transactions through asset sales, mergers, tender
offers, and combinations of those types of transactions. See "Special Factors -
Reasons for the Merger of Each Partnership" for a discussion of why Pioneer
Parent and Pioneer USA selected the proposed transaction. In general, the
contemplated transactions would have been taxable to the limited partners of
each partnership because of the difficulties involved in structuring a tax-free
transaction for the partnership. Until 1999, every time Pioneer Parent or its
predecessors considered such a transaction, it decided not to complete the
transaction. The reasons Pioneer Parent and its predecessors did not previously
complete a transaction varied. In some early cases, they wanted to collect and
fully distribute proceeds to the limited partners of each partnership from
litigation against an oilfield services company before trying to value any
partnership. In other cases, they wanted to avoid periods of volatility in oil
and gas prices or in Pioneer Parent's stock price. On several occasions, Pioneer
Parent was involved in other corporate transactions that could not be completed
timely if a transaction with each partnership was also pending.



     In early 1998, Pioneer Parent was formulating a strategic plan to focus on
its 25 core area oil and gas fields and to eliminate ancillary operations.
Pioneer Parent began discussions internally to consider a transaction involving
each partnership, including the basis for valuing each partnership and whether
the consideration should be Pioneer Parent common stock, cash or some
combination of both.



     During the second quarter of 1998, Pioneer Parent and Pioneer USA began to
discuss the methods for valuing each partnership. At that time, the board of
directors of Pioneer USA engaged Sayles, Lidji & Werbner, A Professional
Corporation (then known as Sayles & Lidji, A Professional Corporation) based in
Dallas, Texas, as its independent legal counsel to assist the board in
evaluating a potential transaction with Pioneer Parent. Pioneer USA's board also
engaged Stanger as its financial advisor to review any proposed transaction and
to render an opinion as to the fairness of the offer price, from a financial
point of view, to the unaffiliated limited partners of each partnership. In May
1998, Pioneer Parent submitted an offer to merge each partnership into Pioneer
USA using Pioneer Parent common stock or a combination of Pioneer Parent common
stock and cash. The pricing for that offer was primarily based on oil and gas
prices and the present value of estimated future net revenues from each
partnership's oil and gas reserves, in each case as of December 31, 1997. The
present value of estimated future net revenues was determined in accordance with
the SEC's reporting convention that provides a common basis for comparing oil
and gas companies and requires the use of oil and gas prices as of the date of
computation, but using a 15% discount rate. After some negotiation with Pioneer
USA, Pioneer Parent withdrew the May 1998 offer due to the decline in oil
prices. In July 1998, Pioneer Parent submitted a second offer using Pioneer
Parent common stock, or at its option upon the occurrence of specified events, a
combination of Pioneer Parent common stock and cash. The oil and gas pricing for
the second offer was lower than the pricing in the May 1998 offer due to the
continued decline in oil prices, but the discount rate for the second offer was
the same as the May 1998 offer. Pioneer Parent and Pioneer USA decided to
discontinue further discussions and not to submit the proposed transaction to
the limited partners of any partnership because of:


     o    the continued decline in oil prices, which in turn would reduce any
          merger value to be paid to the limited partners of each partnership;


     o    the decline in Pioneer Parent's stock price; and



                                      -24-
   35



     o    the tight lending environment for many oil and gas companies,
          including Pioneer Parent.



     As oil and gas prices improved, in June 1999, Pioneer Parent and Pioneer
USA again began discussions internally to consider a transaction involving each
partnership. At that time, Scott Sheffield, the President and Chief Executive
Officer of Pioneer Parent, contacted members of Pioneer USA's board regarding
consideration of a potential transaction involving each partnership. Pioneer
Parent did not submit a written offer to Pioneer USA at that time.



     During the second quarter of 1999, Pioneer Parent and Pioneer USA attempted
to formally address the conflicting interests inherent in the relationships
among Pioneer Parent, Pioneer USA, each partnership and the officers and
directors of Pioneer Parent and Pioneer USA. Pioneer USA caused Scott D.
Sheffield to resign from Pioneer USA's board of directors because he is also a
member of Pioneer Parent's board of directors. He was not replaced. Pioneer USA
did not consider replacing Mr. Sheffield with an unaffiliated director because
Pioneer USA is a 100% subsidiary of Pioneer Parent and typically such
wholly-owned subsidiaries do not have unaffiliated directors. Because all of the
board members of Pioneer USA are also employees of Pioneer Parent, an inherent
conflict exists with respect to their duties to the limited partners of each
partnership in their capacity as directors of Pioneer USA, on the one hand, and
their duties to Pioneer Parent as employees, on the other hand.



     Shortly thereafter, Pioneer USA's board again engaged Sayles, Lidji &
Werbner to advise the board in connection with a proposed transaction with
Pioneer Parent and any other alternative transaction that the board determined
was worth consideration.


     Pioneer USA's board also engaged, on behalf of each partnership, Stanger,
as its financial advisor to advise the board on the fairness from a financial
point of view of the merger value for each partnership to be paid to the
unaffiliated limited partners in the partnership for the limited partnership
interests in the partnership and to assist in Pioneer USA's evaluation of the
merger transaction and other strategic alternatives. Stanger was familiar with
the circumstances from its 1998 engagement.

     On July 14, 1999, Pioneer USA's board met with its counsel and Stanger to
discuss the proposed merger of each partnership. Stanger presented an overview
of the analysis it planned to perform in evaluating the fairness of the proposed
transaction. Stanger advised Pioneer USA's board that Stanger would review the
following for each partnership:

     o    the reserve report to be prepared by Williamson Petroleum Consultants,
          Inc. as of September 30, 1999;

     o    the most recent quarterly financial statements;

     o    the estimated cash distributions;

     o    the estimated net asset value, going concern value and liquidation
          value;

     o    secondary market prices;

     o    tender offers; and

     o    repurchase offers.


Sayles, Lidji & Werbner then reviewed and discussed with the board the
procedures that would be involved in completing the proposed transaction with
Pioneer Parent. The discussion topics included:


     o    the process in which Pioneer USA's board of directors would approve
          the proposed transaction;

     o    the submission of the proposed merger of each partnership to the
          limited partners of the partnership for approval;

     o    the evaluation of offers from third parties;

     o    the application of and compliance with the requirements of the federal
          securities laws; and

     o    the timing of the proposed transaction.

     Members of the Pioneer USA board met informally on several occasions during
July and early August to discuss among each other the proposed terms of the
merger transaction and other potential alternative transactions, including the
formation of a royalty trust or a master limited partnership.


     On August 16, 1999, at a special meeting of the Pioneer USA board, the
board met with representatives of Sayles, Lidji & Werbner and Stanger to discuss
the proposed merger of each partnership into Pioneer USA. Pioneer USA's board
discussed with the representatives of Stanger and Sayles, Lidji & Werbner the
proposed terms of the offer expected from Pioneer Parent, including the expected
pricing parameters of $18 per Bbl of oil and $2.40 per Mcf of gas and the
expected timing of receipt of Pioneer Parent's formal written offer. Stanger
discussed the progress it was making on its financial analysis of each
partnership and its determination of the fairness from a financial point of view
of the merger value for each partnership to be paid in cash for the limited
partners' interests in the partnership. Stanger's discussion centered on (1) the
price to be paid for the oil and gas reserves, (2) the discount rate, (3) the
application of overhead charges and administrative charges, and (4) the
responsibility for any transaction expenses. Following this discussion, the
board and its counsel discussed the board's fiduciary duties in evaluating the
proposed transaction with Pioneer Parent and the making of a recommendation to
the unaffiliated




                                      -25-
   36


limited partners. Finally, the board decided to request that Pioneer Parent make
a formal written offer outlining the terms of the proposed merger transaction.



     On August 17, 1999, in response to Pioneer USA's request for a written
offer, Pioneer Parent delivered to Pioneer USA's board a written proposal which
outlined the terms of the proposed merger transaction. The written offer
specified that the pricing for the oil and gas reserves would be based on 95% of
the arithmetic average of a four-year or five-year NYMEX futures price. The
future cash flows generated by this pricing structure would then be discounted
using a 15% discount rate. At a special meeting that day of Pioneer USA's board,
the board, its counsel and Stanger met to discuss the specifics of Pioneer
Parent's offer, including oil and gas pricing, the present value discount rate,
the right to allow others to bid on the property, and the costs of the merger of
each partnership. Following the board meeting, Pioneer USA's directors
determined that it would be advantageous to each partnership to seek more
favorable pricing terms and a lower discount rate. Thus, the board decided to
continue discussions of the written offer.



     On August 23, 1999, at a special meeting of Pioneer USA's board, the board
updated its counsel and Stanger on the status of its discussions with Pioneer
Parent. As a result of continued discussions, Pioneer Parent and Pioneer USA
agreed, in response to requests by Stanger, (1) to reduce the discount rate from
15% to 12.5%, (2) to increase the pricing of the oil reserves from 95% of the
arithmetic average of a four-year or five-year NYMEX futures price to 100% of
the arithmetic average of the five-year NYMEX futures price, (3) to a fixed
price of $2.40 per Mcf of gas instead of a floating NYMEX futures price and (4)
to allocate the merger expenses and fees to each participating partnership.



     On September 2, 1999, at a special meeting of Pioneer USA's board, the
board and representatives of Stanger and Sayles, Lidji & Werbner reviewed the
terms of a revised proposal submitted by Pioneer Parent which incorporated these
changes. The parties discussed the revised terms of the merger of each
partnership and the strategic rationale for and benefits of the merger of each
partnership. At this meeting, Stanger reviewed with the board its financial
analysis and its evaluation of the merger consideration and the feasibility of
other strategic alternatives. Stanger also orally presented to the board the
status of its findings and its preliminary evaluation of the proposed
transaction.


     After considering Stanger's evaluation of the proposed merger transaction,
Pioneer USA's board, together with representatives of Stanger, engaged in a
general discussion of other possible transactions it had considered over the
last six to eight months. This discussion included anticipated ongoing
operations of each partnership under its current structure and the operation of
each partnership through a master limited partnership structure, as well as
through a royalty trust. The board discussed selling the oil and gas properties
of each partnership at auction and potentially soliciting other buyers or merger
partners. The board also considered the fact that other potential buyers of each
partnership would have an opportunity to make an offer for each partnership
before the board submitted the merger transaction to the limited partners of
each partnership for their consideration and approval.

     At a special meeting held on September 8, 1999, Pioneer USA's board
continued discussions with Sayles, Lidji & Werbner and Stanger regarding the
merger proposals for each partnership. After considering the alternatives
discussed in the preceding paragraph, including the advantages and disadvantages
of each, the board concluded that none of the alternatives was more advantageous
to the limited partners of any partnership than the terms of the proposed merger
of the partnership. The board then unanimously approved proceeding with the
merger of each partnership, subject to determination of September 30, 1999
pricing, its receipt of Stanger's fairness opinion, and the board's
determination that the merger consideration of each partnership is fair to the
unaffiliated limited partners of that partnership based on all circumstances as
of September 30, 1999, including without limitation, the then current market
conditions and the existence, if any, of any other proposal for the partnership
on terms more favorable to the limited partners.


     On September 8, 1999, in connection with the proposed merger transaction,
Pioneer Parent and Pioneer USA filed a preliminary proxy statement and
preliminary Schedule 13e-3s with the Securities and Exchange Commission. In
addition, Pioneer Parent and Pioneer USA publicly announced the proposed merger
of each partnership. In that announcement, Pioneer USA also announced that it
would consider proposals from other potential buyers of one or more of the
partnerships.



     On or about October 19, 1999, Pioneer Parent submitted a verbal offer to
Pioneer USA to revise the oil reserve component of the pricing used in the
preliminary proxy statement to $18.35 per Bbl of oil. On or about November 3,
1999, Pioneer Parent submitted a second verbal offer to Pioneer USA to further
revise the oil reserve pricing to $18.40 per Bbl of oil. Later that month, due
to the increase in oil and gas prices over the previous several months and in
response to a request from Pioneer USA, Pioneer Parent proposed to Pioneer USA
that the merger value calculation for each partnership be further modified (1)
to increase the pricing to $18.90 per Bbl for oil and $2.55 per Mcf of gas and
(2) to increase the discount rate to 15%.



                                      -26-
   37



     On November 17, 1999, in connection with the approval of Pioneer Parent's
capital budget for 2000, Pioneer Parent's board of directors met and voted to
approve the merger of each partnership and to proceed with the completion of
each merger, subject to the pricing information and other relevant conditions at
the time.



     At a special board meeting held on November 22, 1999, Pioneer USA's board
of directors met with representatives from Stanger and Sayles, Lidji & Werbner
to discuss Pioneer Parent's proposed pricing. Pioneer USA's board agreed that an
increase in the merger value for each partnership based on Pioneer Parent's
proposed pricing was warranted to more closely reflect the current oil and gas
prices. Similarly, in view of increases in interest rates during the months
since the original proposal was made and in view of the volatility of oil and
gas prices over the previous year, Pioneer USA's board agreed to increase the
discount rate used to determine the merger value for each partnership from 12.5%
to 15%. Pioneer USA's board reported that management had worked to reduce the
expected merger expenses and fees from an estimated $4.6 million to an estimated
$1.8 million, thereby increasing the merger value for each partnership to be
received by the limited partners of the partnership. The board also received a
status report on whether or not any third party offers had been received since
September 8, 1999, the date on which Pioneer Parent and Pioneer USA announced
that it would consider such offers. In that regard, Pioneer Parent and Pioneer
USA had not received any formal offers, but did receive a few inquiries from
third parties expressing an interest in possibly making a bid on one or more of
the partnerships or the assets of one or more of the partnerships. The nature of
the inquiries was to understand the structure and pricing of the transaction
proposed by Pioneer and Pioneer USA. None of the third parties who made
inquiries (1) specified any terms, (2) made any offer or (3) have pursued the
matter further. The board then voted to extend the period it would be willing to
consider third party offers from November 1, 1999 to December 31, 1999. Stanger
then reviewed for the board Stanger's analysis of the fairness of the merger
transaction using the new terms agreed to by Pioneer Parent and Pioneer USA.
Stanger expressed its preliminary view that the revised merger value for each
partnership to be paid in cash for the limited partnership interests in each
partnership would be fair from a financial point of view to the unaffiliated
limited partners of the partnership under recent market conditions, but stated
that whether or not the transaction would be considered fair by Stanger at the
time its fairness opinion was sought would depend on market conditions at that
time. Following this discussion, the board approved proceeding with the merger
of each partnership on the new terms, subject to (1) its receipt of a fairness
opinion from Stanger, and (2) its determination that the merger value to be paid
in cash for the limited partnership interests in each partnership is fair to the
unaffiliated limited partners of the partnership based on all circumstances,
including without limitation, the then current market conditions and the
existence, if any, of any other proposal for such partnership or its assets on
terms more favorable to the unaffiliated limited partners than the proposed
merger transaction.



     In December 1999, Pioneer became involved in discussions with an
independent oil and gas company similar in size to Pioneer relating to a
corporate merger opportunity. Those discussions required the dedicated time and
attention of Pioneer's management. The corporate merger opportunity subsequently
failed to come to fruition. Meanwhile, during December 1999 and the first
quarter of 2000, oil and gas prices continued to increase. As a result, during
the first quarter of 2000, Pioneer Parent and Pioneer USA began to discuss
revising the pricing terms of the proposed merger transaction to (1) an
arithmetic average of the five-year NYMEX futures price for oil and for gas and
(2) a 15% discount rate. Pioneer Parent also proposed to offer Pioneer Parent
common stock instead of cash to the limited partners of each participating
partnership. In April 2000, Pioneer Parent and Pioneer USA discontinued these
discussions and did not submit the proposed merger transaction to the limited
partners of any partnership because of:



          o    the decline in Pioneer Parent's stock price;


          o    the increase in interest rates; and


          o    Pioneer Parent's involvement in replacing existing debt with new
               publicly-held debt and a new credit facility.



     In September 2000, Pioneer Parent and Pioneer USA began internal
discussions to consider a merger transaction involving 13 privately-held
employee limited partnerships. Pioneer Parent offered to pay an amount of cash
to the limited partners of each participating partnership equal to the sum of
the present value of estimated future net revenues from the partnership's
estimated oil and gas reserves and its net working capital, in each case as of
September 30, 2000, less the cash distributions on October 15, 2000 and November
15, 2000, by the partnership to its partners. Pioneer Parent and Pioneer USA
calculated the present value of the estimated future net revenues from each
partnership's estimated oil and gas reserves using (1) a five-year NYMEX futures
price for oil and gas as of August 25, 2000, with prices held constant after
year five at the year five price, less standard industry adjustments, (2)
historical operating costs adjusted only for those items affected by commodity
prices, such as production taxes and ad valorem taxes, and (3) a 13.5% discount
rate. Pioneer Parent also agreed to bear the merger expenses and fees. Using the
same parameters as described above, Pioneer Parent purchased all of the direct
oil and gas interests held by Scott D. Sheffield, its chairman of the board of
directors and chief executive officer, for $0.2 million during October 2000. The
consideration paid in the mergers of the employee limited partnerships and in
the purchase of the direct oil and gas interests was all cash since offering and
registering Pioneer Parent common stock in those transactions was
cost-prohibitive due to the small size of such transactions. In December 2000,
Pioneer Parent and



                                      -27-
   38



Pioneer USA completed the merger of each of the 13 privately-held employee
limited partnerships with and into Pioneer USA.



     In October 2000, Pioneer Parent terminated the preliminary proxy statement
and preliminary Schedule 13e-3s filed with the Securities and Exchange
Commission on September 8, 1999 in connection with the proposed merger
transaction.



     As oil and gas prices continued to improve, in January 2001, Pioneer Parent
and Pioneer USA renewed their internal discussions to consider a transaction
involving each of the partnerships described in this document. For a discussion
of why Pioneer Parent and Pioneer USA selected the proposed merger transaction,
see "Alternative Transactions to the Merger of Each Partnership" on page 41.
Pioneer Parent offered a combination of its common stock and cash. Pioneer
Parent and Pioneer USA agreed on a merger value for each participating
partnership equal to the sum of the present value of estimated future net
revenues from the partnership's estimated oil and gas reserves and its net
working capital, in each case as of March 31, 2001. Pioneer Parent and Pioneer
USA agreed to calculate the present value of the estimated future net revenues
from each partnership's estimated oil and gas reserves using (1) a five-year
NYMEX futures price for oil and gas as of March 30, 2001, with prices held
constant after year five at the year five price, less standard industry
adjustments, (2) historical operating costs adjusted only for those items
affected by commodity prices, such as production taxes and ad valorem taxes, and
(3) a 13.5% discount rate. For 2001, the oil and gas prices would be based on
the average NYMEX futures price for the nine-month period beginning on April 1,
2001 and ending December 31, 2001. Pioneer Parent also agreed to bear the merger
expenses and fees.



     On February 15, 2001, Pioneer Parent's board of directors met and voted to
approve the merger of each partnership, the issuance of Pioneer Parent common
stock and the payment of cash upon each such merger, and to otherwise proceed
with the completion of each merger, subject to the pricing information and other
relevant conditions at the time.



     During March 2001, Pioneer Parent offered to acquire all of the direct oil
and gas interests owned by some former officers and employees of Pioneer Parent
and Pioneer USA in properties in which Pioneer Parent and Pioneer USA own
interests. The merger value for the direct oil and gas interests was equal to
the present value of estimated future net revenues from the oil and gas reserves
attributable to the interests, as of March 31, 2001. In determining the present
value, Pioneer Parent and Pioneer USA used (1) a five-year NYMEX futures price
for oil and gas as of March 19, 2001 with prices held constant after year five
at the year five price, less standard industry adjustments, (2) historical
operating costs adjusted only for those items affected by commodity prices, such
as production taxes and ad valorem taxes, and (3) a 13.5% discount rate. The
consideration offered in the purchases of the direct oil and gas interests was
all cash since offering and registering Pioneer Parent common stock in those
purchases was cost-prohibitive due to the small size of such transactions.


     In April 2001, Pioneer USA contacted Sayles, Lidji & Werbner and Stanger to
advise them of the proposed merger transaction, pricing terms and merger
consideration.

     On April 9, 2001, Pioneer USA's board met with Sayles, Lidji & Werbner to
discuss the proposed merger of each partnership into Pioneer USA. The board
members reviewed the terms of the merger transaction, including the pricing
terms, the merger consideration and the terms and conditions of the proposed
merger agreement. The board members also discussed the engagement of special
legal counsel to render the legal opinion required by each partnership's
partnership agreement. Finally, Pioneer USA's board discussed the fairness
opinion to be delivered by Stanger and decided to hold another board meeting at
which Stanger would present in detail its methodology in determining that the
merger value for each partnership and the allocation of the merger value of the
partnership (1) to the limited partners of the partnership as a group, (2) to
the general partners of the partnership as a group, (3) to Pioneer USA as the
managing or sole general partner of the partnership, (4) to the unaffiliated
limited partners of the partnership as a group and (5) to the unaffiliated
limited partners of the nonmanaging general partner, if any, of the partnership
as a group, is fair to the unaffiliated limited partners of the partnership and
the unaffiliated limited partners of the nonmanaging general partner, if any, of
the partnership, from a financial point of view. The board decided to proceed
with the merger transaction, but would withhold recommending the merger
transaction to the limited partners or executing the merger agreement until it
received the fairness opinion from Stanger and determined that the merger of
each partnership is advisable, fair to the unaffiliated limited partners and in
the unaffiliated limited partners' best interests


     On April 17, 2001, in connection with the proposed merger transaction,
Pioneer Parent and Pioneer USA filed a registration statement on Form S-4 and
preliminary Schedule 13e-3s with the Securities and Exchange Commission. In
addition, Pioneer Parent and Pioneer USA publicly announced the proposed merger
of each partnership. In that announcement, Pioneer USA also announced that it
would continue to consider proposals from other potential buyers of any
partnership or its assets.



     On May 7, 2001, Pioneer USA received proposed solicitation materials
prepared by Sierra Fund 3 indicating that Sierra Fund planned to make a tender
offer for up to 4.9% of the limited partnership interests of Parker & Parsley
88-A, L.P. and Parker & Parsley 89-A, L.P. at a price equivalent to $200 and
$240 per $1,000 initial investment, respectively, in each of the partnerships.
Sierra Fund requested and received a list of limited partners of these
partnerships. On June 28, 2001, Pioneer USA learned that on June 14, 2001 Sierra
Fund made a tender offer for up to 4.9% of the limited partnership interests of
Parker & Parsley 83-A, Ltd., Parker & Parsley 83-B, Ltd., Parker & Parsley 84-A,
Ltd. and Parker & Parsley 85-A, Ltd. at a price equivalent to $85, $75, $110 and
$80 per $1,000 investment, respectively, in each of the partnerships.


                                      -28-
   39






     Three other limited partners have expressed interest to Pioneer USA in
either making offers for the assets of particular partnerships or in purchasing
the limited partnership interests of other limited partners. In May 2001,
Salvage Investors, L.L.C. expressed interest in making an offer for the assets
of Parker & Parsley 82-I, Ltd. but did not indicate a price at which it would be
willing to purchase those assets. Also in May 2001, Horace Potts IV expressed
interest in making an offer for the assets of unspecified partnerships or,
alternatively, in soliciting higher offers on the assets of those partnerships,
but did not indicate a price at which he would be willing to purchase those
assets. In June 2001, Nancy R. Schauer expressed interest in purchasing limited
partnership interests of Parker & Parsley 87-A Conv., Ltd., Parker & Parsley
87-B Conv., Ltd. and Parker & Parsley Private Investment 88, L.P. Pioneer USA
received a copy of correspondence from Ms. Schauer to the limited partners of
those partnerships in which Ms. Schauer asked the limited partners to vote
against the proposed mergers and to call her if they wanted to sell their
limited partnership interest.



     Additionally, in May 2001 James A. Smith of Indigo Ventures requested, and
Pioneer later sent to him, a list of the limited partners of Parker & Parsley
Private Investment 89, L.P. and Parker and Parsley 90 Spraberry Private
Development, L.P. Pioneer Parent and Pioneer USA do not know if Mr. Smith
contacted any limited partners of those partnerships.



     In late April 2001, Stanger contacted members of Pioneer USA's board and
expressed concern regarding the pricing terms of the merger transaction. Based
on Stanger's updated analysis of the new pricing terms for the merger
transaction, Stanger questioned whether merger value was fair to the
unaffiliated limited partners of the partnerships and the unaffiliated limited
partners of the nonmanaging general partners of the partnerships from a
financial point of view. After internal discussions between members of Pioneer
USA's board and Stanger to discuss pricing terms which Stanger and the Pioneer
USA board believed would be fair to the unaffiliated limited partners of the
partnerships and the unaffiliated limited partners of the nonmanaging general
partners of the partnerships from a financial point of view, the Pioneer USA
board requested that Stanger meet with Pioneer Parent to discuss the issue.
Stanger met with Pioneer Parent on June 15, 2001, to discuss new pricing terms
that were more favorable to the partnerships.



     On June 18, 2001, in follow-up discussions between Pioneer Parent, Pioneer
USA and Stanger, Pioneer Parent and Pioneer USA orally agreed, subject to the
approval of their respective boards, to revise the pricing terms of the merger
transaction as follows: (1) that the merger value for each partnership would
equal the sum of the partnership's reserve value and its working capital, in
each case as of March 31, 2001, less the cash distribution to be paid in July
2001 and less the partnership's pro rata share of expenses and fees to be
incurred in connection with the mergers of all of the partnerships, except that
Pioneer Parent will pay (A) any such expenses and fees in excess of $2,000,000
in the aggregate and (B) a portion of such expenses and fees otherwise allocable
to any nonparticipating partnership, (2) to reduce the discount rate that would
be used in calculating the present value of the estimated future net revenues
from 13.5% to 10%, (3) to change the composition of the payment of the merger
value for each partnership from 25% in cash and 75% in shares of Pioneer Parent
common stock to 100% in shares of Pioneer Parent common stock based on the
average closing price of the Pioneer Parent common stock, as reported by the New
York Stock Exchange, for the ten trading days ending three days business days
before the date of the special meeting of the partnership, and (4) to engage
Williamson Petroleum Consultants, Inc. to review the estimate of each
partnership's reserves and the present value of the estimated future net
revenues from those estimated reserves as of March 31, 2001. The effect of the
revised pricing terms was to increase the merger consideration that would be
paid to each of the participating partnerships upon completion of the merger
transaction.



     On June 21, 2001, Pioneer Parent's board met and approved the revised
pricing terms.



     At a special meeting held on June 21, 2001, Pioneer USA's board continued
discussions with Sayles, Lidji & Werbner and Stanger regarding the merger
proposals for each partnership. Stanger also orally presented to Pioneer USA's
board the status of its findings and its preliminary evaluation of the proposed
transaction based on the new pricing terms for the merger transaction. Pioneer
USA's board decided that it would take the approval of the merger of each
partnership under advisement, so that the board members could review the written
presentation materials provided by Stanger and the revised written offer to be
submitted by Pioneer Parent, and agreed to convene a special meeting on June 25,
2001.



     On June 22, 2001, Pioneer submitted its written offer with the revised
pricing terms to Pioneer USA.



     On June 25, 2001, Pioneer USA's board held a special meeting with Sayles,
Lidji & Werbner and Stanger to discuss the merger proposals for each partnership
and Stanger's fairness opinion. The board then unanimously approved proceeding
with the merger of each partnership, subject to (1) the execution of a
definitive merger agreement, (2) its receipt of Stanger's fairness opinion, and
(3) its receipt of the Securities and Exchange


                                      -29-
   40



Commission's declaration that the registration statement, that includes this
document, is effective under the Securities Act of 1933.



     In a special meeting of the board of Pioneer USA held on            , 2001,
Stanger presented its opinion dated           , 2001, that the merger value for
each partnership and the allocation of the merger value of the partnership (1)
to the limited partners of the partnership as a group, (2) to the general
partners of the partnership as a group, (3) to Pioneer USA as the managing or
sole general partner of the partnership, (4) to the unaffiliated limited
partners of the partnership as a group and (5) to the unaffiliated limited
partners of the nonmanaging general partner, if any, of the partnership as a
group, is fair to the unaffiliated limited partners of the partnership and the
unaffiliated limited partners of the nonmanaging general partner, if any, of the
partnership, from a financial point of view. The board of Pioneer USA then
unanimously determined that the merger proposals for each partnership are
advisable, fair to the unaffiliated limited partners and in the unaffiliated
limited partners' best interests. Accordingly, the board recommended that the
unaffiliated limited partners of each partnership vote for the merger proposals.
References to Pioneer USA's board's recommendation of the merger of each
partnership and its finding that the merger consideration is fair from a
financial point of view are stated in this preliminary document conditioned on
the execution of a definitive merger agreement and its receipt of Stanger's
fairness opinion, which are expected to occur when the registration statement
that includes this document is declared effective under the Securities Act of
1933.


REASONS FOR THE MERGER OF EACH PARTNERSHIP


     General. For all of the reasons listed below, Pioneer Parent believes that
it is the party in the position to pay the highest price for the limited
partnership interests of each partnership. Pioneer USA also believes that
Pioneer Parent is the most likely buyer for each partnership's properties in
light of:


     o    Pioneer USA's operation of most of the properties;

     o    Pioneer USA's extensive property holdings in the same fields; and


     o    Pioneer Parent's ability to achieve efficiencies by consolidating
          operations with its existing operations in the same areas.



     Pioneer Parent's Reasons. Pioneer Parent believes that completion of the
merger of each partnership at this time is advantageous to it for the following
reasons:



     o    Consolidate Core Area of Operations. The Spraberry field of the
          Permian Basin is one of Pioneer Parent's 25 fields of focus in its
          strategic plan. Acquisition of each partnership's properties would
          help consolidate Pioneer Parent's operations in the Spraberry field
          and achieve operating efficiencies. Pioneer USA operates most of each
          partnership's wells, and Pioneer Parent has extensive properties
          around each partnership's properties, including interests in most of
          each partnership's wells.



     o    Achieve Operating Efficiencies. Pioneer Parent expects to improve
          operating efficiencies with respect to the properties acquired in the
          merger of each partnership because it will be able to co-mingle
          production of oil from each participating partnership's properties
          with production of oil from other Pioneer Parent properties for
          storage, transportation and sale. Production of oil from each
          partnership's properties is predominantly segregated from Pioneer
          Parent's production of oil until sale. Gas production is currently,
          and will continue to be, metered, which means that it is measured and
          allocated based on ownership.



     o    Achieve Administrative Efficiencies. Pioneer Parent will eliminate the
          costs, including time spent by Pioneer Parent employees, related to
          preparing and filing each partnership's separate tax returns,
          financial statements and, for each reporting partnership, reports with
          the SEC, as well as dealing with the concerns of approximately 29,000
          record limited partners. The merger of each partnership will result in
          administrative efficiencies and cost reductions in the management and
          operation of the properties now owned by each partnership,
          particularly in the areas of audit, accounting and tax services,
          engineering services, bookkeeping, data processing, record maintenance
          and mailing information to the partners. Although Pioneer Parent will
          lose the benefit of each partnership's reimbursement for general and
          administrative expenses, it will be able to use the additional time of
          its personnel to help achieve its corporate strategic goals.


     Pioneer USA's Reasons. In considering the merger of each partnership, the
board of directors of Pioneer USA considered the benefits to the limited
partners of each partnership set forth on page 7 as well as the following
factors:


     o    Maturity of Partnerships and Properties. Although each partnership's
          properties were long-lived at the formation of the partnership, each
          partnership's properties are now mature, ranging from approximately 10
          to approximately 20 years old. Pioneer Parent and Pioneer USA
          anticipated that at some point each



                                      -30-
   41

          partnership would need to be liquidated. Pioneer USA is recommending
          the merger transaction for each partnership at this time because:


          -    Pioneer USA believes that Pioneer Parent is the most likely buyer
               and is the only potential buyer with an offer outstanding. While
               third parties have made inquiries, no one except Pioneer Parent
               has made an offer to Pioneer USA to acquire any of the
               partnerships.



          -    Oil and gas prices have recovered from significant lows in 1998.
               As a result, Pioneer USA believes that Pioneer Parent's pricing
               is higher than it would have been otherwise.



          -    As our production continues to decline, administrative expenses
               for each partnership are increasing on a per BOE produced basis.
               Moreover, the administrative cost of continuing to produce each
               partnership to depletion could be significant, especially if no
               buyer is available at the time each partnership is shut down.



          -    As discussed below, the tax incentive for which each partnership,
               other than Parker & Parsley Producing Properties 87-A, Ltd.,
               Parker & Parsley Producing Properties 87-B, Ltd. and Parker &
               Parsley Producing Properties 88-A, L.P., was originally formed
               has been realized.


     o    Declining Cash Flows. As each partnership's properties have matured,
          the net cash flows from operations for the partnership have generally
          declined, except in periods of substantially increasing commodity
          prices. See Table 7 of Appendix A for each partnership's historical
          cash distributions. The marginal benefit of continuing the operations
          of each partnership is offset by the related administrative costs.
          These administrative costs consume an increasing amount, and
          ultimately will consume the entire amount, of the cash flows of each
          partnership as production declines.


     o    Tax Incentive Has Been Realized. Each partnership, other than Parker &
          Parsley Producing Properties 87-A, Ltd., Parker & Parsley Producing
          Properties 87-B, Ltd. and Parker & Parsley Producing Properties 88-A,
          L.P., was intended to provide to its partners federal income tax
          deductions for intangible drilling and development costs incurred by
          the partnership in the initial years of investment. Pioneer USA
          believes that the tax incentives have generally been realized.


     o    Partnership Tax Burdens May Now Exceed Benefits. As net cash flow
          available for distribution of each partnership has declined or, at
          times, disappeared, some limited partners of the partnership may incur
          greater costs to include their share of the tax information of the
          partnership in their returns than they receive in cash distributions.
          In any event, all limited partners of each partnership are expected to
          benefit by the elimination of the obligation to include partnership
          information in their tax returns for the years after the merger of
          each partnership in which they own interests.


     o    Each Partnership is Unable to Access Additional Capital. Pioneer
          Parent, through its subsidiary, Pioneer USA, has the ability,
          financial and otherwise, to take advantage of corporate opportunities
          to expand its reserve base through acquisitions. None of the
          partnerships has the ability to raise capital for reserve
          acquisitions. The partnership agreements of the partnerships do not
          authorize the partnerships to raise additional capital, whether debt
          or equity. Even if the partnership agreement of each partnership is
          amended to authorize additional capital, Pioneer Parent does not
          believe that the limited partners of the partnership would desire to
          contribute additional capital or to apply all cash flow to debt
          service, while remaining taxable on the related income.


     o    Fairness of Procedures. Pioneer USA considered the following factors
          in making its recommendation that the unaffiliated limited partners
          vote for the merger proposals for each partnership in which they own
          interests:


          -    None of the partnerships has any employees or directors, and all
               of Pioneer USA's directors are officers of Pioneer USA and of
               Pioneer Parent. As a result, there has been no approval by
               directors who are not Pioneer Parent employees.


          -    Pioneer USA did not retain an unaffiliated representative to act
               solely on behalf of the unaffiliated limited partners of each
               partnership for purposes of negotiating the terms of the merger
               of the partnership or preparing a report concerning the fairness
               of the merger of the partnership.

          -    Since Pioneer USA is entitled to vote its limited partnership
               interests other than as described below, the transaction is not
               structured so that the approval of at least a majority of
               unaffiliated limited partnership interests is required. Pioneer
               USA intends to vote in favor of the transaction for the
               partnership interests it holds as a limited partner of each
               partnership as permitted by the partnership agreement of each
               partnership except in the following partnerships where the
               partnership agreement does not allow Pioneer USA to vote on the
               proposed transaction:


                                      -31-
   42


                      Parker & Parsley 85-A, Ltd.
                      Parker & Parsley 85-B, Ltd.
                      Parker & Parsley Private Investment 85-A, Ltd
                      Parker & Parsley Selected 85 Private Investment, Ltd
                      Parker & Parsley Private Investment 86, Ltd.
                      Parker & Parsley 91-A, L.P.
                      Parker & Parsley 91-B, L.P.

          Despite the foregoing factors, Pioneer USA believes each merger is
          procedurally fair to the unaffiliated limited partners of each
          partnership because:


          -    Pioneer USA has been willing to consider any offer from third
               parties to purchase any partnership or the assets of any
               partnership since September 8, 1999, and will continue to do so
               through August 1, 2001; and



          -    Pioneer Parent does not directly own any partnership interests in
               the partnerships. Pioneer Parent beneficially owns all of Pioneer
               USA's partnership interests in the partnerships. Pioneer USA does
               not beneficially own more than 5% of the outstanding limited
               partnership interests in any partnership, except Parker & Parsley
               81-I, Ltd., Parker & Parsley 82-I, Ltd. and Parker & Parsley
               82-III, Ltd. In those partnerships, Pioneer USA repurchased and
               now owns partnership interests representing the following
               beneficial ownership percentages:


                      Parker & Parsley 81-I, Ltd.                        5.84%
                      Parker & Parsley 82-1, Ltd.                       10.73%
                      Parker & Parsley 82-III, Ltd.                      5.97%


               Except as set forth above, none of Pioneer Parent, Pioneer USA,
               or, to the knowledge of Pioneer USA, any of their directors or
               executive officers, or any associate or subsidiary of Pioneer
               Parent, Pioneer USA beneficially owns any partnership interests
               of any partnership. As a result, Pioneer USA believes that
               neither it nor its affiliates have a meaningful voting percentage
               for any partnership, other than Parker & Parsley 81-I, Ltd.,
               Parker & Parsley 82-I, Ltd. and Parker & Parsley 82-III, Ltd. See
               "Ownership of Partnership Interests" on page 64 of this document
               and Table 6 of Appendix A to this document.


     o    Fairness of Transaction. Pioneer USA's board of directors determined
          that the merger of each partnership is advisable, fair to the
          unaffiliated limited partners of the partnership and in their best
          interests. In reaching this determination for each partnership,
          Pioneer USA's board of directors considered the following factors:

          -    The form and amount of consideration offered to the partners of
               the partnership;

          -    The objectives of the merger of the partnership, including
               providing liquidity to the partners;

          -    Pioneer USA's right to consider third party offers;

          -    The current market prices for oil and gas, including the increase
               in market prices, and the subsequent increase in merger value for
               the partnership, since the merger transaction was initially
               proposed in 1999;

          -    The historical market prices for oil and gas;

          -    The net book value, going concern value and liquidation value of
               the partnership;

          -    The purchase prices paid in previous repurchases by Pioneer USA;

          -    The trading price of limited partnership interests in secondary
               market transactions

          -    The analysis of alternative transactions to the proposed merger
               of each partnership; and

          -    The fairness opinion of Stanger, including the analyses conducted
               by Stanger in rendering the fairness opinion.


RECOMMENDATION OF PIONEER USA


     On            , 2001, Pioneer USA's board of directors unanimously
determined that the merger of each partnership is advisable, fair to the
unaffiliated limited partners of the partnership, and in their best interests.
PIONEER USA'S


                                      -32-
   43

BOARD OF DIRECTORS RECOMMENDS THAT THE UNAFFILIATED LIMITED
PARTNERS VOTE FOR THE MERGER PROPOSALS FOR EACH PARTNERSHIP IN WHICH THEY OWN
INTERESTS.

     In making this recommendation, Pioneer USA's board of directors considered
a number of factors, including (1) the reasons for the merger of each
partnership set forth above in "Special Factors -- Reasons for the Merger of
Each Partnership," such as the fairness opinion and analyses conducted by
Stanger, and (2) the matters described under "Risk Factors" beginning on page 17
of this document, such as its conflicting interests. Pioneer USA's board of
directors also considered the likelihood, benefits and costs of other
transactions, including possible third party offers. Pioneer USA will consider
any offers from third parties to purchase any partnership or its assets. See
"The Merger of Each Partnership -- Third Party Offers" on page 52 of this
document for a description of the procedures for these offers. In view of the
numerous factors taken into consideration, Pioneer USA's board of directors did
not consider it practical to, and did not attempt to, quantify or assign
relative weights to the factors considered by it in reaching its decision to
recommend the merger of each partnership. Rather, the board viewed its position
and recommendation as being based on the total information presented to and
considered by the board.

FAIRNESS OPINION


     Pioneer USA, on behalf of each partnership, engaged Robert A. Stanger &
Co., Inc., an independent financial advisory firm, to conduct an independent
review and deliver a written opinion in connection with the merger of each
partnership that the merger value for each partnership and the allocation of the
merger value of the partnership (1) to the limited partners of the partnership
as a group, (2) to the general partners of the partnership as a group, (3) to
Pioneer USA as the managing or sole general partner of the partnership, (4) to
the unaffiliated limited partners of the partnership as a group and (5) to the
unaffiliated limited partners of the nonmanaging general partner, if any, of the
partnership as a group, is fair to the unaffiliated limited partners of the
partnership and the unaffiliated limited partners of the nonmanaging general
partner, if any, of the partnership, from a financial point of view. The full
text of Stanger's fairness opinion is attached as Appendix D to this document
and is incorporated into this document by reference. Limited partners of each
partnership are urged to read the opinion in its entirety. This summary of
Stanger's fairness opinion is qualified in its entirety by reference to the full
text of the opinion. Stanger has advised us that arriving at a fairness opinion
is a complex analytical process not necessarily susceptible to partial analysis
or amenable to summary description. For a more complete description of the
assumptions and qualifications to the fairness opinion see "Qualifications to
Fairness Opinion" beginning below on this page and "Assumptions" on page 39.


     Except for assumptions which Pioneer USA advised Stanger would be
reasonable and appropriate in its view, neither Pioneer USA nor any partnership
imposed any conditions or limitations on the scope of the investigation by
Stanger or the methods and procedures to be followed by Stanger in rendering the
fairness opinion. In addition, each partnership has agreed to indemnify Stanger
against some liabilities arising out of Stanger's engagement to prepare and
deliver its opinion upon consummation of the merger of the partnership, and such
indemnification obligations will become obligations of Pioneer USA.

     Experience of Stanger. Since its founding in 1978, Stanger has provided
information, research, investment banking and consulting services to clients
located throughout the United Sates, including major New York Stock Exchange
member firms and insurance companies and over seventy companies engaged in the
management and operation of partnerships. The investment banking activities of
Stanger include financial advisory and fairness opinion services, asset and
securities valuations, industry and company research and analysis, litigation
support and expert witness services, and due diligence investigations in
connection with both publicly registered and privately placed securities
transactions.


     Stanger was selected because of its experience in the valuation of
businesses and their securities in connection with mergers, acquisitions,
reorganizations and for estate, tax, corporate and other purposes, including the
valuation of partnerships, partnership securities and the assets typically held
through partnerships including oil and gas assets. Pioneer USA has previously
engaged Stanger to provide financial advisory services in connection with
proposed transactions between one or more of the partnerships and Pioneer Parent
which were never consummated.


     Qualifications to Fairness Opinion. In the fairness opinion, Stanger
specifically states that it was not requested to, and did not:

     o    make any recommendations to Pioneer USA, any partnership or the
          limited partners of any partnership with respect to whether to approve
          or reject the merger of any partnership;

     o    determine or negotiate the amount or form of the merger value for any
          partnership to be paid for limited partners' interests in the merger
          of the partnership;

     o    offer the assets of any partnership for sale to any third party;

     o    express any opinion as to:


                                      -33-
   44


          -    the impact on Pioneer USA or the limited partners of any
               partnership that does not participate in the proposed merger
               transaction;

          -    the tax consequences of the merger of any partnership for Pioneer
               USA, the nonmanaging general partner, if any, of the partnership
               or the limited partners of the partnership;


          -    Pioneer USA's or Pioneer Parent's ability to finance their
               obligations under the merger agreement or the impact of a failure
               to obtain financing on the financial performance of Pioneer USA,
               Pioneer Parent or any partnership;



          -    Pioneer USA's decision to estimate the reserve value of the oil
               and gas reserves of each partnership based upon the continued
               operation of the properties by Pioneer USA and the payment of
               overhead charges in accordance with existing operating agreements
               or the impact, if any, on the estimated value of each
               partnership's oil and gas reserves if Pioneer Parent and Pioneer
               USA determined to offer or operate the assets subject to revised
               operating agreements;


          -    whether or not alternative methods of determining the merger
               value for each partnership would have also provided fair results
               or results substantially similar to the methodology used;

          -    alternatives to the merger of each partnership, including the
               offering of such assets for sale to third party buyers;


          -    the trading price of shares of Pioneer Parent common stock
               immediately following the closing of the merger of each
               partnership and the distribution of shares of Pioneer Parent
               common stock in connection with the merger of each partnership;


          -    the fairness of the termination of the repurchase obligations of
               Pioneer USA with respect to some partnerships, which repurchase
               obligations require Pioneer USA to offer to repurchase limited
               partnership interests annually based upon a formula which in some
               circumstances, including the repurchase offers based upon
               December 31, 2000 oil and gas prices, result in repurchase offer
               prices above the market value for the reserves of any such
               partnership; or

          -    any other terms of the merger of any partnership.

     Summary of Material Considered and Investigation Undertaken. Stanger's
analysis of the merger of each partnership involved a review of the following
information:

     o    a draft of this preliminary document;

     o    a draft of the merger agreement which Pioneer USA has indicated is
          substantially the form which will be executed in connection with the
          merger of each partnership;


     o    financial statements of each partnership, including, if applicable,
          the partnership's Form 10-Q and Form 10-K, for the three months ended
          March 31, 2001 and for the years ended December 31, 2000, 1999 and
          1998;



     o    the reserve reports prepared by Pioneer Parent and Pioneer USA and the
          review by Williamson Petroleum Consultants, Inc., as of March 31,
          2001, relating to the reserves of each partnership;



     o    calculations prepared by Pioneer Parent and Pioneer USA of the merger
          value per $1,000 of limited partner investment in each partnership;


     o    Pioneer USA's analysis of other alternatives to the merger of each
          partnership, including going concern value, liquidation value, royalty
          trust and production payment;


     o    estimates prepared by Pioneer Parent and Pioneer USA of the merger
          value, going concern value and liquidation value per $1,000 of limited
          partner investment in each partnership;



     o    the financial statements of Pioneer Parent included in its Form 10-Q
          for the three months ended March 31, 2001 and its Form 10-K for the
          years ended December 31, 2000, 1999 and 1998;



     o    pro forma financial data for Pioneer Parent assuming the completion of
          the proposed merger transaction; and



     o    recent trading activity in shares of Pioneer Parent common stock.



                                      -34-
   45



     In the course of its analysis, Stanger conducted interviews of senior
management personnel of Pioneer USA. During such interviews, Stanger and the
senior management personnel reviewed the status of the merger of each
partnership, the reserve pricing and related value estimates, the estimated
timing of the merger of each partnership and other matters.


     Stanger reviewed estimates of the merger value, going-concern value, and
liquidation value prepared by Pioneer USA with respect to each partnership. In
addition, Stanger reviewed secondary market prices, as tracked by Stanger, for
limited partnership interests in each partnership along with tender offers
received by limited partners as derived from data provided by Pioneer USA.
Stanger's analysis is summarized below.


     Review of Merger Value for Each Partnership. Stanger reviewed the
calculation of the merger value for each partnership prepared by Pioneer USA.
Stanger observed that such calculation includes the reserve value, as described
below, and other current assets as of March 31, 2001, as reduced by other
current liabilities as of March 31, 2001, less the partnership's pro rata share,
based on its reserve value, of the estimated expenses and fees of the mergers of
all of the partnerships and less the cash distribution to be mailed on or about
July 12, 2001, by the partnership to its partners. Stanger reviewed the balance
sheet of each partnership as of March 31, 2001 as prepared by Pioneer USA, and
reconciled the current assets and current liabilities on such financial
statements to the balances included in the merger value calculation for each
partnership.



     Stanger reviewed the summary reserve reports for each partnership prepared
by Pioneer Parent and Pioneer USA as reviewed by Williamson Petroleum
Consultants, Inc. as of March 31, 2001. Stanger noted that the summary reserve
report was prepared based upon the following pricing case: (1) a five-year NYMEX
futures price for oil and gas as of March 30, 2001, with prices held constant
after year five at the year five price and (2) historical operating costs
adjusted only for those items affected by commodity prices, such as production
taxes and ad valorem taxes. For 2001, the oil and gas prices were based on the
average NYMEX futures price for the nine-month period beginning on April 1, 2001
and ending December 31, 2001. The standard industry adjustments reflect oil
quality, BTU content, oil and gas gathering and transportation costs, and gas
processing costs and shrinkage.



     Stanger further observed that the summary reserve report utilized a
discount rate of 10.0% and resulted in a per barrel of oil equivalent, or BOE,
value of the reserves for each of the partnerships ranging from $3.53 to $4.61.
Stanger observed that such BOE values are low by general industry averages.
However, Stanger observed that such properties are long-lived, generally
low-volume properties, not operated by any of the partnerships, and are subject
to overhead charges by the operator, Pioneer USA. In the course of its
engagement, Stanger reviewed selected comparable transactions in the BOE value
range described above for long-lived, generally low-volume properties. Such
transactions, including some transactions involving other Pioneer USA
affiliates, provided a range of value per BOE of $2.97 to 5.08 and an average of
$4.00.



     Stanger, in connection with its engagement, interviewed acquisitions
personnel at seven oil and gas companies regarding targeted pricing case ranges
and discount rate ranges in order to assess the reasonableness of the pricing
case and discount rates utilized to establish the reserve value for the
partnerships. With respect to the pricing case ranges, Stanger observed a low
pricing case range pursuant to the survey of $22 per barrel of oil and $3.50 per
Mcf of gas, held flat for the life of the reserves to a high pricing case range
of NYMEX strip pricing (plus $2 per barrel of oil) and NYMEX strip pricing for
gas, held flat after five years for the life of the reserves. With respect to
discount rates, Stanger observed a range of discount rates from a low of 9% to
13% applied generally to a low range pricing case to a high range of 15% to 20%,
applied generally to a high range pricing case. Stanger concluded that the
pricing case and discount rates utilized to establish the merger value for each
partnership fall within the ranges established in interviews with acquisition
professionals.


     Going Concern Value. Stanger reviewed the going concern value calculation
prepared for each partnership by Pioneer USA. The going concern value was based
upon:


     o    The sum of (1) the estimated net cash flow from sale of the reserves
          during a 10-year operating period and (2) the estimated residual value
          from the sale of the remaining reserves at the end of the operating
          period, in each case using the same pricing and discount rate as in
          the merger value calculation; less


     o    Partnership level general and administrative expenses, calculated as
          follows and, consistent with the calculation of 2000 and 1999
          expenses, generally representing the maximum expense percentages
          permitted under the partnership agreements:

          -    The partnership agreement for each of Parker & Parsley 81-I,
               Ltd., Parker & Parsley 81-II, Ltd., Parker & Parsley 82-I, Ltd.,
               Parker & Parsley 82-II, Ltd. and Parker & Parsley 82-III, Ltd.
               permits Pioneer USA to allocate to the partnership (1) general
               and administrative expenses and (2) all expenses directly
               attributable to the partnership as a result of fees or charges by
               parties other than Pioneer USA or its affiliates, including
               legal, auditing and engineering fees. However, for purposes of
               clause (1) and for administrative ease and to the benefit of each
               of those partnerships, Pioneer USA allocates to each of those
               partnerships general and administrative expenses based on 3% of
               the revenues of the partnership.


                                      -35-
   46



          -    The partnership agreement for each of Parker & Parsley 83-A, Ltd.
               and Parker & Parsley 83-B, Ltd. permits Pioneer USA to allocate
               to the partnership (1) general and administrative expenses in an
               annual amount not to exceed the sum of 2% of the initial partner
               capital for the partnership and 2.25% of the drilling and
               completion expenses, of which there are none, and (2) all
               expenses directly attributable to the partnership as a result of
               fees or charges by parties other than Pioneer USA or its
               affiliates, including legal, auditing and engineering fees.
               However, for purposes of clause (1) and for administrative ease
               and to the benefit of each of those partnerships, Pioneer USA
               allocates to each of those partnerships general and
               administrative expenses based on 3% of the revenues of the
               partnership.



          -    The partnership agreement for Parker & Parsley 84-A, Ltd. permits
               Pioneer USA to allocate to the partnership (1) general and
               administrative expenses in an annual amount not to exceed the sum
               of 3.25% of the revenues of the partnership and 2.25% of the
               drilling and completion expenses, of which there are none, and
               (2) all expenses directly attributable to the partnership as a
               result of fees or charges by parties other than Pioneer USA or
               its affiliates, including legal, auditing and engineering fees.
               However, for purposes of clause (1) and for administrative ease
               and to the benefit of the partnership, Pioneer USA allocates to
               the partnership general and administrative expenses based on 3%
               of the revenues of the partnership.


          -    The partnership agreement for each of the following partnerships
               permits Pioneer USA to allocate to the partnership general and
               administrative expenses, including all expenses directly
               attributable to the partnership as a result of fees or charges by
               parties other than Pioneer USA or its affiliates, such as legal,
               auditing and engineering fees, in an annual amount not to exceed
               2% of the revenues of the partnership.

                  Parker & Parsley Private Investment 85-A, Ltd.
                  Parker & Parsley Selected 85 Private Investment, Ltd.
                  Parker & Parsley Private Investment 86, Ltd.

          -    The partnership agreement for each of the following partnerships
               permits Pioneer USA to allocate to the partnership general and
               administrative expenses, including all expenses directly
               attributable to the partnership as a result of fees or charges by
               parties other than Pioneer USA or its affiliates, such as legal,
               auditing and engineering fees, in an annual amount not to exceed
               3% of the revenues of the partnership.

                  Parker & Parsley 85-A, Ltd.
                  Parker & Parsley 85-B, Ltd.
                  Parker & Parsley 86-A, Ltd.
                  Parker & Parsley 86-B, Ltd.
                  Parker & Parsley 86-C, Ltd.
                  Parker & Parsley 87-A Conv., Ltd.
                  Parker & Parsley 87-A, Ltd.
                  Parker & Parsley 87-B Conv., Ltd.
                  Parker & Parsley 87-B, Ltd.
                  Parker & Parsley Producing Properties 87-A, Ltd.
                  Parker & Parsley Producing Properties 87-B, Ltd.
                  Parker & Parsley Private Investment 87, Ltd.
                  Parker & Parsley 88-A Conv., L.P.
                  Parker & Parsley 88-A, L.P.
                  Parker & Parsley 88-B Conv., L.P.
                  Parker & Parsley 88-B, L.P.
                  Parker & Parsley 88-C Conv., L.P.
                  Parker & Parsley 88-C, L.P.
                  Parker & Parsley Producing Properties 88-A, L.P.
                  Parker & Parsley Private Investment 88, L.P.

          -    The partnership agreement for each of the following partnerships
               permits Pioneer USA to allocate to the partnership (1) general
               and administrative expenses in an annual amount not to exceed 3%
               of the revenues of the partnership, and (2) all expenses directly
               attributable to the partnership as a result of fees or charges by
               parties other than Pioneer USA or its affiliates, including
               legal, auditing and engineering fees.

                  Parker & Parsley 89-A Conv., L.P.
                  Parker & Parsley 89-A, L.P.
                  Parker & Parsley 89-B Conv., L.P.
                  Parker & Parsley 89-B, L.P.


                                      -36-
   47


                  Parker & Parsley 90-A Conv., L.P.
                  Parker & Parsley 90-A, L.P.
                  Parker & Parsley 90-B Conv., L.P.
                  Parker & Parsley 90-B, L.P.
                  Parker & Parsley 90-C Conv., L.P.
                  Parker & Parsley 90-C, L.P.
                  Parker & Parsley 91-A, L.P.
                  Parker & Parsley 91-B, L.P.

          -    The partnership agreement for each of the following partnerships
               permits Pioneer USA to allocate to the partnership (1) general
               and administrative expenses in an annual amount not to exceed 5%
               of the revenues of the partnership, and (2) all expenses directly
               attributable to the partnership as a result of fees or charges by
               parties other than Pioneer USA or its affiliates, including
               legal, auditing and engineering fees. However, for purposes of
               clause (1) and for administrative ease and to the benefit of each
               of the partnerships, Pioneer USA allocates to the partnership
               general and administrative expenses based on 3% of the revenues
               of the partnership.

                  Parker & Parsley Private Investment 89, L.P.
                  Parker & Parsley Private Investment 90, L.P.
                  Parker & Parsley 90 Spraberry Private Development, L.P.


     Stanger observed that the going concern value of each partnership was
adjusted for the March 31, 2001 working capital balance less the distribution to
be mailed on or about July 12, 2001 and that such going concern value ranged
from 4.6% to 10.0% less than the merger value for each partnership. See the
supplemental information table on the second page of the supplement for each
partnership for its merger value and its going concern value, in each case per
$1,000 limited partner investment.



     Liquidation Value. Stanger reviewed the liquidation value calculation
prepared for each partnership by Pioneer USA. Such liquidation value was based
upon the sale of the reserves at the reserve value, less liquidation expenses
which are estimated to be the sum of (1) the partnership's pro rata share of the
estimated expenses and fees of the mergers of all of the partnerships and (2) 3%
of the partnership's reserve value. The liquidation expenses represent the
estimated costs to retain an investment banker or broker to sell the assets of
each partnership and the legal and other closing costs associated with such
transaction. Stanger observed that such merger expenses are intended to reflect
Pioneer USA's estimate of the cost associated with brokers' commissions on asset
sales and the additional wind-down costs of the partnership. Stanger observed
that the liquidation value for each partnership ranged from 2.7% to 3.0% less
than the merger value for each partnership. See the supplemental information
table on the second page of the supplement for each partnership for its merger
value and its liquidation value, in each case per $1,000 limited partner
investment.



     Secondary Market Prices. To determine the most up-to-date secondary market
prices, Stanger reviewed the secondary market prices for units of limited
partnership interests in each of the partnerships during the 12 months ended
April 30, 2001, collected from data maintained on partnerships by Stanger.
Stanger observed that secondary market transactions were reported for 25 of the
partnerships during such period. Stanger observed that for all partnerships
except Parker & Parsley 81-II, Ltd. and Parker & Parsley Producing Properties
87-A, Ltd., the weighted average secondary market price on a per $1,000 original
investment basis was less than the merger value per $1,000 original investment.
For such other partnerships, the range of discount to the merger value per
$1,000 investment was 5.2% to 52.7%, averaging 27.7%. For Parker & Parsley
81-II, Ltd., Stanger observed that only one transaction involving $35,000 of
original investment (7 units) was at a price in excess of the merger value. For
Parker & Parsley Producing Properties 87-A, Ltd., Stanger observed that only one
transaction involving $10,000 of original investment (20 units) was at a price
in excess of the merger value per $1,000 of original investment. All other
secondary market transactions for Parker & Parsley Producing Properties 87-A,
Ltd. were reported at prices below the merger value. Stanger also observed
secondary market transactions at prices in excess of the merger value for one
additional partnership. Secondary market firms reported a single transaction
during the twelve months ended April 30, 2001 for Parker & Parsley 82-II, Ltd.
at a price in excess of merger value. All other transactions reported for such
partnerships were at amounts less than the merger value during the twelve months
ended April 30, 2001.


     Stanger also reviewed the secondary market data obtained by Pioneer USA
from Partnership Spectrum and included in Table 15 of Appendix A to this
document. Stanger observed that such data included partnerships which reported a
secondary market transaction price in excess of the high-end transaction price
Stanger observed in its data. In all cases, such high-end range was lower than
the merger value.


     Prices in the secondary market are based on market prices at the time of
the secondary market transaction, which prices may be lower than prices
prevailing at March 30, 2001 or as of the date of mailing this document.



     Selected Tender Offers. Stanger observed that Pioneer USA reported
unsolicited tender offers from unaffiliated third parties for less than 5% of
the interests in the following partnerships during the period June 1998 through
June



                                      -37-
   48


2001. Stanger observed that the tender offers and related merger value per
limited partnership interest for each of those partnerships were as follows:





                                                        MERGER VALUE            TENDER OFFER                DISCOUNT TO
                   PARTNERSHIP                   (PER $1,000 INVESTMENT)   (PER $1,000 INVESTMENT)         MERGER VALUE
                   -----------                   -----------------------   -----------------------    --------------------
                                                                                              
Parker & Parsley 82-II, Ltd.                             $101.61                    $13.75                   (86.5%)
Parker & Parsley 82-III, Ltd.                             121.72                     26.25                   (78.4%)
Parker & Parsley 83-A, Ltd.(a)                            141.43                40.00 to 70.00          (50.5%) to (71.7%)
Parker & Parsley 83-B, Ltd.(a)                            154.41                50.00 to 55.00          (64.4%) to (67.6%)
Parker & Parsley 84-A, Ltd.                               201.43                     60.00                   (70.2%)
Parker & Parsley 86-A, Ltd.                               177.09                     40.00                   (77.4%)
Parker & Parsley 86-B, Ltd.                               224.17                    115.00                   (48.7%)
Parker & Parsley 86-C, Ltd.(a)                            161.23                65.00 to 67.50          (58.1%) to (63.7%)
Parker & Parsley 87-A, Ltd.(a)                            190.81                90.00 to 105.00         (45.0%) to (52.8%)
Parker & Parsley 87-B, Ltd.(a)                            201.38                60.00 to 65.00          (67.7%) to (70.2%)
Parker & Parsley 88-A, L.P.                               245.95                     80.00                   (67.5%)
Parker & Parsley 88-B, L.P.                               321.02                     50.00                   (84.4%)
Parker & Parsley Private Investment 89, L.P.              270.69                    162.50                   (40.0%)
Parker & Parsley 90-B, L.P.(a)                            265.39               102.50 to 160.00         (39.7%) to (61.4%)
Parker & Parsley 90-C, L.P.(a)                            243.26                30.00 to 40.00          (83.6%) to (87.7%)
Parker & Parsley 90 Spraberry Private Dev., L.P.          288.51                    162.50                   (43.7%)



---------
(a)  More than one tender offer for partnership interests was made. Amounts
     shown represent the range of tender offer prices.


     Stanger observed that the above tender offers represent a discount to the
merger value for each of those partnerships of 39.7% to 87.7%. Stanger also
observed that tender offers for limited partnership securities are generally at
prices which represent a substantial discount to the underlying value of the
assets held by such partnerships. Furthermore, the tender offer prices are based
on oil prices prevailing at the time of the tender offer, which prices may have
been lower than oil prices prevailing at March 30, 2001 or as of the date of
mailing this document.


     Repurchase Offers. Stanger observed that for each of the six partnerships
listed below, which Stanger calls the repurchase partnerships, Pioneer USA is
required under the partnership agreement for the partnership to offer to
repurchase units of limited partnership interests in the partnership annually at
a formula price based upon the December 31 year end reserve report. Stanger
observed that the repurchase offer pricing at December 31, 2000 tends to
overstate the value of units of the repurchase partnerships due primarily to the
oil and gas prices in effect on such date and the effect of such pricing on the
cash flows and recoverable reserves. Stanger observed that the repurchase offers
for 2000 for the repurchase partnerships are at premiums to the merger value
ranging from 25.5% to 68.5% as follows:




                                         PER $1,000 ORIGINAL INVESTMENT
                                   -----------------------------------------
                                   MERGER VALUE   REPURCHASE OFFER   PREMIUM
                                   ------------   ----------------   -------
                                                           
Parker & Parsley 82-I, Ltd.          $ 80.06        $137.97           72.3%
Parker & Parsley 82-II, Ltd.          101.61         133.72           31.6%
Parker & Parsley 82-III, Ltd.         121.72         150.59           23.7%
Parker & Parsley 83-A, Ltd.           141.43         196.67           39.1%
Parker & Parsley 83-B, Ltd.           154.41         210.15           36.1%
Parker & Parsley 84-A, Ltd.           201.43         267.03           32.6%





     Stanger observed that the repurchase rights may be exercised only once a
year and that a limited partner may exercise its repurchase right by delivering
a written request to Pioneer USA no later than March 31 of each year. Pioneer
USA advised Stanger that on or before May 31 of each year, Pioneer USA must
notify each limited partner who has exercised its repurchase right of the amount
of limited partnership interests to be repurchased and the method of calculating
the repurchase price. Pioneer USA advised Stanger that the aggregate amount of
limited partnership interests required to be repurchased in any one year is
limited to $100,000 per partnership. A repurchase price is calculated by
multiplying:



                                      -38-
   49



     o    the present value of the estimated future net revenues, calculated
          using a discount rate equal to prime plus 1% as of December 31 of each
          year, from a partnership's estimated reserves, as determined by
          independent petroleum consultants; by



     o    66 2/3%.



Stanger advised that each limited partner who has exercised its repurchase right
has 60 days to accept Pioneer USA's repurchase offer and that Pioneer USA must
pay the repurchase price to each limited partner who accepts the repurchase
offer within 30 days after acceptance.



     Stanger further advised Pioneer USA and each repurchase partnership that no
adjustment was made to the merger value offered to the repurchase partnership to
reflect the repurchase offer obligation and Stanger's opinion does not include
an opinion as to the fairness of the termination of Pioneer USA's repurchase
obligation.



     Assumptions. Pioneer Parent and Pioneer USA advised Stanger that the oil
and gas properties owned by each partnership are subject to operating agreements
with Pioneer USA and that:


     o    such operating agreements provide for the payment of overhead charges
          and that such charges are reasonable compared with amounts charged for
          similar services by third party operators;

     o    except for cause, such operating agreements do not provide for the
          termination of Pioneer USA as operator; and

     o    such operating agreements do not provide for the revision of the
          overhead charges, except as escalated under the terms of such
          operating agreements.


Furthermore, Pioneer Parent and Pioneer USA advised Stanger that if each
partnership's reserves were offered for sale to a third party, a condition of
such sale would be that the oil and gas reserves would continue to be subject to
the operating agreements with Pioneer USA which provide for the payment of
overhead charges, and that it would be appropriate to assume, when estimating
the value of such reserves, that such charges would continue.



     In addition, Pioneer Parent and Pioneer USA advised Stanger that the
reserve value and working capital balance of each partnership has been properly
allocated between the general partners and the limited partners of each
partnership in accordance with the partnership agreement with respect to a
liquidation.



     Stanger did not conduct any engineering studies and has relied on estimates
of Pioneer Parent and Pioneer USA with respect to oil and gas reserve volumes,
prices, operating costs and overhead charges with respect to the reserve value
estimates. Furthermore, Stanger has relied upon the review by Williamson of the
summary reserve reports as of March 31, 2001.



     Stanger also relied on the assurance of Pioneer Parent, Pioneer USA and
each partnership that:



     o    the summary reserve report reviewed by Williamson Petroleum
          Consultants, Inc. as of March 31, 2001, and provided to Stanger was in
          the judgment of Pioneer USA and each partnership reasonably prepared
          on bases consistent with actual historical experience and reflect
          their best currently available estimates and good faith judgments;


     o    there are no estimates of costs to remediate environmental conditions
          included in the reserve analysis;

     o    any historical financial data, balance sheet data, merger value
          analyses, going concern value analyses and liquidation value analyses
          are accurate and complete in all material respects;

     o    all allocations included in the calculations of merger values, going
          concern values and liquidation values have been made in accordance
          with the partnership agreement of each partnership;

     o    no material changes have occurred in the information reviewed or in
          the value of the oil and gas reserves or working capital balances of
          each partnership between the date the information was provided to
          Stanger and the date of Stanger's opinion;

     o    the relative ownership interests of (1) the limited partners of each
          partnership, (2) the unaffiliated limited partners of each
          partnership, (3) the general partners of each partnership, (4) the
          unaffiliated limited partners of the nonmanaging general partner, if
          any, of each partnership and (5) Pioneer USA, as the managing or sole
          general partner of each partnership, is accurately included in
          accordance with the partnership agreement for each partnership in the
          analyses provided to Stanger by Pioneer USA;


                                      -39-
   50

     o    neither Pioneer Parent or any of its affiliates has during the thirty
          days prior to the date hereof commenced or continued a share
          repurchase program or similar transaction which could affect the price
          of shares of Pioneer Parent common stock to be used in the proposed
          merger transaction; and




     o    Pioneer Parent, Pioneer USA and each partnership are not aware of any
          information or facts regarding the partnership, the oil and gas
          properties, the reserve analysis or the working capital balances of
          the partnership that would cause the information supplied to Stanger
          to be incomplete or misleading in any material respect.


     Stanger's opinion is based upon business, economic, oil and gas market and
other conditions as of the date of its analysis and addresses the merger value
for each partnership in the context of information available as of the date of
Stanger's analysis. Events occurring after the date of Stanger's analysis could
affect the value of the assets of each partnership or the assumptions used in
the preparation of Stanger's fairness opinion.

     Conclusions. Stanger concluded that, based upon and subject to its
analysis, assumptions, limitations and qualifications cited in its opinion, and
as of the date of the fairness opinion, the merger value for each partnership
and the allocation of the merger value of the partnership (1) to the limited
partners of the partnership as a group, (2) to the general partners of the
partnership as a group, (3) to Pioneer USA as the managing or sole general
partner of the partnership, (4) to the unaffiliated limited partners of the
partnership as a group and (5) to the unaffiliated limited partners of the
nonmanaging general partner, if any, of the partnership as a group, is fair to
the unaffiliated limited partners of the partnership and the unaffiliated
limited partners of the nonmanaging general partner, if any, of the partnership,
from a financial point of view.

     Compensation and Material Relationships. Stanger has been paid a total fee
of $350,000 in connection with the rendering of the fairness opinion. Such fee
was not conditioned on Stanger's findings and is payable whether or not the
merger of each partnership is consummated. In addition, Stanger will be
reimbursed for all reasonable out-of-pocket expenses, including legal fees, and
will be indemnified against some liabilities, including some liabilities under
the securities laws. To the extent that such indemnification includes
liabilities arising under the federal securities laws, it may not be enforceable
as it may be determined to be against public policy.

     During the past two years, Pioneer USA engaged Stanger to render financial
advisory services in connection with proposed transactions which were withdrawn
and never consummated. In connection with such assignments Stanger was paid fees
aggregating $175,000.

SUMMARY RESERVE REPORT


     Pioneer USA engaged Williamson Petroleum Consultants, Inc., an independent
petroleum engineering consulting firm based in Midland, Texas, to review a
summary reserve report of the property interests of each of the partnerships as
of March 31, 2001. THE FULL TEXT OF THE REVIEW OF THE SUMMARY RESERVE REPORT BY
WILLIAMSON PETROLEUM CONSULTANTS, INC. EFFECTIVE AS OF MARCH 31, 2001, IS
ATTACHED AS APPENDIX B. WE ENCOURAGE YOU TO READ IT CAREFULLY IN ITS ENTIRETY.


     Qualifications and Method of Selection. Williamson is engaged solely in the
business of petroleum evaluation and engineering studies for public and private
oil and gas companies. Williamson is widely recognized in its field. Williamson
is an independent consulting firm as provided in the Standards Pertaining to the
Estimating and Auditing of Oil and Gas Reserves Information promulgated by the
Society of Petroleum Engineers.

     Pioneer USA engaged Williamson based upon Pioneer USA's assessment of their
professional reputations and qualifications, capabilities, experience and
responsiveness. In addition, Williamson is the independent petroleum engineering
firm most familiar with the properties in which each partnership has interests
and has prepared the annual independent reserve report for each partnership's
reserves since the inception of each partnership.


     Summary of Procedures, Scope and Findings. Williamson reviewed the
calculations of the estimated total net estimated reserves for each partnership
and the present value of the estimated future net revenues from the estimated
reserves for each partnership as of March 31, 2001, based on the following
parameters provided by Pioneer USA: (1) a five-year NYMEX futures price for oil
and gas as of March 30, 2001 with prices held constant after year five at the
year five price, less standard industry adjustments, (2) historical operating
costs adjusted only for those items affected by commodity prices, such as
production taxes and ad valorem taxes, and (3) a 10.0% discount rate. For 2001,
the oil and gas prices were based on the average NYMEX futures price for the
nine-month period beginning on April 1, 2001 and ending December 31, 2001.
Williamson's estimated total net estimated reserves and the present value of the
estimated future net revenues from the estimated reserves for each partnership
are set forth in the exhibits to the summary reserve report attached as Appendix
B to this document.



     Pioneer Parent determined the amount of Pioneer Parent common stock to be
offered. Williamson did not opine on the fairness of the transaction.



                                      -40-
   51



     In preparing its summary reserve report, Williamson assumed the accuracy
and completeness of all information provided by Pioneer USA or information which
was publicly available and did not attempt to independently verify such
information. Williamson did not make field inspections or judgments relative to
environmental or other legal liabilities. Except as described in this document,
Pioneer USA did not instruct Williamson as to the pricing, cost or other
economic parameters or methods or the assessment of reserves characteristics,
nor did it limit the scope of Williamson's investigation for purposes of
preparing its summary reserve report.


     Pioneer USA provided Williamson with all evaluation data with respect to
interests, reversionary status, oil and gas prices, gas categories, gas contract
terms, operating expenses, investments, salvage values, abandonment costs, net
profit interests, well information and current operating conditions for
Williamson's use in determining each partnership's reserves. Williamson used
production data provided by Pioneer USA, and where information was not provided
by Pioneer USA, Williamson used production data from public records. Williamson
prepared its own reserve estimates of the property interests.

     Prior Material Relationships. Williamson has estimated total proved
reserves and the present value of estimated future revenues from those reserves
for each of the partnerships since their respective inceptions. In addition,
Pioneer USA engaged Williamson to prepare a summary reserve report in connection
with a proposed transaction in 1999, similar to the one described in this
document, which was withdrawn and never consummated. Pioneer USA and its
affiliates have paid $112,700 over the past two years to Williamson. Neither
Williamson nor any of its personnel has any direct or indirect interest in
Pioneer USA or any of the partnerships, and Williamson's compensation is not
contingent upon the results of its summary reserve report.

ALTERNATIVE TRANSACTIONS TO THE MERGER OF EACH PARTNERSHIP

     We considered the following alternative types of transactions before
selecting the merger transaction described in this document. As discussed below,
we believe that the merger of each partnership is the best available alternative
for each partnership to maximize the consideration to the limited partners.

     Comparison of the Merger of Each Partnership to Continuing Operations.
Because each partnership's properties are mature, producing properties, we
believe that production from those properties will continue to decline at the
rate predicted in the partnership's oil and gas engineering reserve reports.
Accordingly, cash distributions from each partnership will also decline, subject
to variation for changes in oil and gas prices. The marginal benefit of
continuing operations of each partnership is offset by the general and
administrative costs related to continuing operations. See "Special Factors --
Reasons for the Merger of Each Partnership" beginning on page 29 of this
document.


     We also believe there is a substantial advantage in receiving the
liquidating distribution at present in the form of Pioneer Parent common stock,
rather than continuing to receive decreasing levels of cash distributions over a
long period of time. We believe that the reserve value included in the merger
value for each partnership is higher than the net present value of estimated
future cash distributions to the limited partners from continued operations
because the reserve value has not been reduced for the reimbursement of Pioneer
USA's general and administrative expenses allocable to the partnership. In
addition, although future oil and gas prices could be higher than the prices on
March 30, 2001 which were used in calculating the merger value for each
partnership, continued operations over a long period of time subject the limited
partners of each partnership to the risk of receiving lower levels of cash
distributions if oil and gas prices over this period are lower on average than
those used in preparing the estimates of cash distributions from continued
operations. Continued operations also subject the limited partners of each
partnership to possible changes in costs or need for workover or similar
significant remedial work on each partnership's properties. In contrast, the
Pioneer Parent common stock is a liquid tradeable security which can be sold and
redeployed in other investments. The Pioneer Parent common stock provides the
limited partners of each partnership the opportunity to participate in a larger
entity having more diversified producing reserves and other oil and gas
properties, with the resulting spreading of risks.


     We expect that any nonparticipating partnership will continue operations
and will produce its reserves until depletion with steadily decreasing rates of
cash flow and, as a result, decreasing cash distributions.


     Comparison of the Merger of Each Partnership to Master Limited Partnership.
We considered accomplishing the consolidation of each partnership through a
master limited partnership, pursuant to which the partnership interests of the
limited partners of the partnership would be exchanged for interests in the
master limited partnership. However, we believe each partnership's oil and gas
properties are not of sufficient size, individually or in the aggregate with the
other partnerships, to attract new capital through a master limited partnership.
In addition, the partnership interests in a master limited partnership might not
be traded on a national stock exchange or in any other significant market. Some
master limited partnership interests might be sold from time to time in private
or over-the-counter transactions, but the prices would likely reflect a discount
for illiquidity. As a result, we believe a master limited partnership would not
provide the limited partners with immediate and complete liquidity for their
investment in each partnership. Finally, a master limited partnership would
still be burdened with general and administrative expenses, which would reduce
any cash distributions paid to the partners of the master limited



                                      -41-
   52


partnership. The merger value for each partnership reflects a liquidation value
and has not been reduced for any reimbursement of Pioneer USA's general and
administrative expenses allocable to the partnership.


     Comparison of the Merger of Each Partnership to Royalty Trust. We also
considered a royalty trust, pursuant to which the partnership interests of each
partnership would be exchanged for beneficial ownership interests in the trust.
Like the master limited partnership alternative discussed above, we believe each
partnership's oil and gas properties are not of sufficient size, individually or
in the aggregate with the other partnerships, to attract new capital through a
royalty trust. In addition, the beneficial ownership interests in a royalty
trust might not be publicly traded in a significant market. As a result, this
alternative was not selected because we believe it would not result in immediate
and complete liquidity for the limited partners' investments in any partnership.
Finally, a royalty trust would still be burdened with general and administrative
expenses, which would reduce any cash distributions paid to the beneficiaries of
the royalty trust. The merger value for each partnership reflects a liquidation
value and has not been reduced for any reimbursement of Pioneer USA's general
and administrative expenses allocable to the partnership.



     Comparison of the Merger of Each Partnership to Production Payment. We also
considered whether each partnership would benefit from attempting to sell a
production payment against its future oil and gas production in exchange for
cash. Like the master limited partnership and royalty trust alternatives
discussed above, we believe each partnership's oil and gas properties are not of
a sufficient size, individually or in the aggregate with the other partnerships,
to attract new capital from lenders or investors. In addition, lenders or
investors that provide production payment alternatives will not advance funds
against 100% of future oil and gas production, and typically limit any
production payment transaction to less than 70% of estimated future oil and gas
production. As a result, this alternative was not selected because we believe it
would not provide the limited partners with immediate and complete liquidity for
their investment in each partnership. Even with a production payment
transaction, each partnership would continue to be burdened with general and
administrative expenses which would reduce any cash distributions paid to the
limited partners. The merger value for each partnership reflects a liquidation
value and has not been reduced for any reimbursement of Pioneer USA's general
and administrative expenses allocable to the partnership.



     Comparison of the Merger of Each Partnership to Negotiated Sale. We also
considered whether each partnership would benefit from attempting to sell its
property interests in negotiated transactions. Buyers would be purchasing the
partnership's property interests which they would neither control nor operate. A
portion of the properties in which each partnership owns interests would
continue to be operated by Pioneer USA because Pioneer USA controls other
interests in fields in which the partnership's properties are located. Because
of Pioneer USA's control of such properties, Pioneer Parent and Pioneer USA
believe Pioneer Parent is the party in the position to pay the highest price for
such interests and the one most likely to do so. In contrast, Pioneer USA's
control of such properties could negatively affect the amount a third party is
willing to pay and the overall interest of third parties in buying such
properties.



     In addition, sale of each partnership's properties on a direct basis often
involves substantial periods of time for due diligence, negotiation and
execution of agreements and closings, often with different purchasers for
different properties. Satisfying due diligence requests requires large amounts
of time to create and supervise data rooms or disseminate data to possible
purchasers, plus the time needed to deal directly with multiple prospective
purchasers. Furthermore, some issues, such as environmental and title matters,
may come to light in the late stages of a negotiated sale, which may delay or
preclude the consummation of the sale.


     The transaction costs for offering properties in a negotiated sale could be
substantial, and often are higher than other means of sale. Those costs include:

     o    preparing and disseminating information on properties to be offered;

     o    soliciting attendance by prospective purchasers; and

     o    screening and qualifying purchasers.


     In a third party sale, we expect that each partnership would have to pay
its own expenses or that the price would be reduced to take the expenses into
account.



     Although we believe the factors described above to be true, we are
conducting a limited form of auction. That is, in September 1999 we established
a price and publicly announced that we will consider third party offers to
purchase any partnership or its assets at prices that are higher than the 1999
merger value for such partnership. We have repeated our willingness to consider
third party offers in connection with the merger of each partnership we now
propose, so long as the prices offered exceed those we are offering. We believe
this process would result in a better price to the limited partners than if we
merely offered the partnership or its assets for sale at any price. Pioneer
Parent has the right to match or top any third party offer. In addition, any
such offer would be subject to our right to continue operation of the
properties. See "The Merger of Each Partnership -- Third Party Offers" on page
52.


                                      -42-
   53


Although we received some preliminary indications of interest from third parties
during the last quarter of 1999, none of those third parties has ever made a
formal bid for any partnership or its assets.

                           FORWARD-LOOKING STATEMENTS


     This document includes "forward looking statements" as defined by the
Securities and Exchange Commission. These statements concern Pioneer Parent's,
Pioneer USA's and each partnership's plans, expectations and objectives for
future operations. All statements, other than statements of historical facts,
included in this document that address activities, events or developments that
Pioneer Parent, Pioneer USA and each partnership expect, believe or anticipate
will or may occur in the future are forward looking statements and include the
following:


     o    completion of the proposed merger of each partnership;

     o    reserve estimates;

     o    future production of oil and gas; and

     o    future financial performance.


     These forward looking statements are based on assumptions, which Pioneer
Parent, Pioneer USA and each partnership believe are reasonable, but which are
open to a wide range of uncertainties and business risks. Factors that could
cause actual results to differ materially from those anticipated are discussed
in (1) "Risk Factors" beginning on page 17 of this document, (2) periodic
filings with the Securities and Exchange Commission, including Annual Reports on
Form 10-K for the year ended December 31, 2000, for Pioneer Parent and each
reporting partnership, and (3) "Management's Discussion and Analysis of
Financial Condition and Results of Operations" for the year ended December 31,
2000 included in the supplement to this document for each nonreporting
partnership.


     "Safe Harbor" Statement under the Private Securities Litigation Reform Act
of 1995: Statements in this document regarding each company's business which are
not historical facts are "forward looking statements" that involve risks and
uncertainties. For a discussion of these risks and uncertainties, which could
cause actual results to differ from those contained in the forward looking
statements, see "Risk Factors" beginning on page 17 of this document.


                                      -43-
   54



             METHOD OF DETERMINING MERGER VALUE FOR EACH PARTNERSHIP
                AND AMOUNT OF PIONEER PARENT COMMON STOCK OFFERED



     Pioneer Parent and Pioneer USA agreed to a merger value for each
partnership for purposes of the merger of the partnership. The method of
determining the merger value for each partnership was not determined by
arm's-length negotiations. See "Risk Factors -- You Were Not Independently
Represented in Establishing the Terms of the Merger of Each Partnership" on page
17 and "Interests of Pioneer Parent, Pioneer USA and Their Directors and
Officers" on page 63.



     In March 2001, Pioneer Parent and Pioneer USA agreed to use March 31, 2001
to determine the merger value for each partnership and to base the number of
shares of Pioneer Parent common stock to be offered on the average closing price
of the Pioneer Parent common stock, as reported by the New York Stock Exchange,
for the ten trading days ending three business days before the initial date of
the special meeting for each partnership. For purposes of illustration in this
document, we have calculated the number of shares to be issued based on an
assumed average closing price of $18.00 per share of Pioneer Parent common
stock. Prior to the date of the special meeting for each partnership, we will
update the number of shares to be issued using the actual average closing price
of Pioneer Parent common stock for the ten trading days ending three business
days before the initial date of the special meeting. Neither Pioneer Parent nor
Pioneer USA will adjust any of the other components of the merger value for any
partnership.


COMPONENTS OF MERGER VALUE FOR EACH PARTNERSHIP


     Pioneer Parent and Pioneer USA calculated the merger value assigned to each
partnership as follows:



     o    Pioneer Parent and Pioneer USA agreed to use the volumes of the
          partnership's estimated reserves as of March 31, 2001, as taken from
          the summary reserve report reviewed by Williamson Petroleum
          Consultants, Inc. as of March 31, 2001.



     o    Pioneer Parent and Pioneer USA agreed to use the present value of
          estimated future net revenues for each partnership from the estimated
          reserves for each partnership at March 31, 2001, as taken from the
          summary reserve report reviewed by Williamson Petroleum Consultants,
          Inc. as of March 31, 2001. The reserve value component of the merger
          value for each partnership is also set forth in Table 16 of Appendix A
          to this document. Pioneer Parent and Pioneer USA instructed Williamson
          to use the following parameters in calculating the present value of
          estimated future net revenues: (1) a five-year NYMEX futures price for
          oil and gas as of March 30, 2001, with prices held constant after year
          five at the year five price, less standard industry adjustments, (2)
          historical operating costs adjusted only for those items affected by
          commodity prices, such as production taxes and ad valorem taxes, and
          (3) a discount rate of 10.0%. For 2001, the oil and gas prices were
          based on the average NYMEX futures price for the nine-month period
          beginning on April 1, 2001 and ending December 31, 2001. See the table
          on page 6 for the NYMEX futures prices. Pioneer Parent and Pioneer USA
          believe that the five-year NYMEX futures prices provide a reasonable
          benchmark on the outlook for energy prices and are regularly used by
          financial markets, industry participants, and lenders in evaluating
          transactions.


          -    The standard industry price adjustments include:

               (1)  the effects of oil quality;

               (2)  British thermal unit, or BTU, content for gas;

               (3)  any bonus paid;

               (4)  oil and gas gathering and transportation costs; and

               (5)  gas processing costs and shrinkage.

               Those adjustments reflect assumptions about the costs to extract,
               transport and process, if necessary, crude oil, natural gas
               liquids and natural gas to their point of sale.


          -    Pioneer Parent and Pioneer USA agreed to use a 10.0% discount
               rate because Pioneer Parent believes that a 10% discount rate is
               necessary based upon the risks involved in the oil and gas
               industry and Pioneer Parent's requirement to achieve a minimum
               rate of return on its investment.



     o    Pioneer Parent and Pioneer USA added the present value of the
          partnership's estimated future net revenues as of March 31, 2001 to
          the partnership's net working capital as of March 31, 2001 and then
          reduced that sum by (i) the partnership's pro rata share, based on its
          reserve value, of the estimated expenses and fees of the mergers of
          all of the partnerships and (2) the cash distribution to be mailed on
          or about July 12, 2001,



                                      -44-
   55



          by the partnership to its partners. Since the merger value for each
          partnership includes net working capital, the merger value assigned to
          the partnership includes the partnership's assets and liabilities
          other than its oil and gas reserves. Each partnership's other assets
          and liabilities consist mainly of cash, accounts receivable from the
          sale of oil and gas production and accounts payable.



     o    The number of shares of Pioneer Parent common stock to be issued to
          the limited partners of each partnership upon the merger of the
          partnership will be determined by dividing the merger value assigned
          to the partnership by the value of one share of Pioneer Parent common
          stock determined as described below. For purposes of example in this
          document, a share of Pioneer Parent common stock has been valued at an
          assumed average closing price of $18.00. However, on the closing date
          of the merger of each partnership, the value of a share of Pioneer
          Parent common stock will be recalculated by computing the average
          closing price of the Pioneer Parent common stock, as reported by the
          New York Stock Exchange, for the ten trading days ending three
          business days before the initial date of the special meeting for each
          partnership. This recalculated value, and not the assumed average
          closing price of $18.00 per share of Pioneer Parent common stock, used
          for illustration purposes in this document and on each limited
          partner's proxy card, will be used to determine the actual number of
          shares of Pioneer Parent common stock to be issued in the merger of
          each partnership. The recalculated value may be more or less than the
          assumed average closing price of $18.00 per share of Pioneer Parent
          common stock. Pioneer Parent may abandon the proposed merger of any or
          all of the partnerships at any time prior to the special meeting for
          any such partnership for any reason including changes in, among other
          things, the price of Pioneer Parent common stock, the market prices
          for oil and gas generally or the oil and gas industry generally.



     Distributions. No cash distributions will be made by any partnership to its
partners after the distribution in July 2001 through the closing date or
termination date of the merger of the partnership. The Pioneer Parent common
stock to be distributed as payment of the merger value of each participating
partnership already reflects the expected amount of those distributions.
However, any cash distributions by a nonparticipating partnership which would
have been paid during that time period in the ordinary course of that
partnership's business will be distributed to its partners at about the same
time that the certificates representing Pioneer Parent common stock are mailed
to the partners of each participating partnership.


     Liabilities. Pioneer USA will assume all of the liabilities, including
contingent liabilities and obligations, of each participating partnership as of
the closing date of the merger of the partnership. As of the date of this
document, Pioneer USA is not aware of any material contingent liabilities to
which any partnership is subject.


     Expenses. The expenses and fees to be incurred in connection with the
merger of each partnership are expected to be approximately $2.0 million in
total. Each participating partnership will pay its pro rata share, based on its
reserve value, of those estimated expenses and fees. Each nonparticipating
partnership will pay a portion of the estimated expenses and fees of the mergers
otherwise allocable to the partnership based on a fraction, the numerator of
which is the percentage of the partnership's limited partnership interests that
are voted in favor of the merger proposals and the denominator of which is the
percentage of the partnership's limited partnership interests for which votes
are cast. Pioneer Parent has agreed to pay (1) the remainder of the estimated
expenses and fees otherwise allocable to such nonparticipating partnership, (2)
any expenses and fees actually incurred in excess of $2.0 million, and (3) if
Pioneer Parent terminates or abandons the merger as to any partnership, any
expenses or fees allocated to that partnership. Pioneer Parent and Pioneer USA
have reduced each partnership's merger value by that partnership's pro rata
share of the estimated expenses and fees.


ALLOCATION OF MERGER VALUE FOR EACH PARTNERSHIP AMONG PARTNERS OF THE
PARTNERSHIP


     In determining the portion of the merger value attributable to each $1,000
of initial limited partner investment in a partnership, Pioneer Parent
determined the amount payable per $1,000 investment as if the assets of the
partnership had been sold on March 31, 2001 for cash equal to the merger value
of the partnership and the proceeds distributed in accordance with the
liquidation provisions of the partnership's partnership agreement. The limited
partners of each participating partnership would receive the same amounts if the
merger value of the partnership was allocated among the partners based on the
revenue-sharing provisions of the partnership agreement except for each of the
following partnerships which will receive more proceeds under the liquidation
provisions of its respective partnership agreement than under its
revenue-sharing provisions due to certain prospect-by-prospect payout provisions
not being met:


                  Parker & Parsley 81-I, Ltd.
                  Parker & Parsley 81-II, Ltd.
                  Parker & Parsley 82-I, Ltd.
                  Parker & Parsley 82-II, Ltd.
                  Parker & Parsley 82-III, Ltd.


                                      -45-
   56


OTHER METHODS OF DETERMINING MERGER VALUES


     Pioneer Parent and Pioneer USA believe that the method used to determine
the merger value for each partnership is a fair and reasonable method of valuing
the partnership's properties. Pioneer Parent and Pioneer USA considered a number
of alternative methods of determining the merger value for each partnership
before selecting a method. However, the selected method might not accurately
reflect the value of each partnership's assets. See "Risk Factors -- Risk
Factors Relating to the Merger of Each Partnership -- The Merger Values for a
Partnership Will Not be Adjusted For Changes in Oil and Gas Prices Before the
Completion of Its Merger" on page 18. The following alternative methods for
determining the merger value for each partnership should be taken into account
in assessing the adequacy of the selected method.



     Book Value of Assets. Pioneer Parent and Pioneer USA did not base the
calculation of merger value for each partnership on the net book value of the
partnership's assets. The net book value of each partnership's assets is based
upon the financial statements reported in accordance with generally accepted
accounting principles. The net book value is not adjusted for estimates in
changes in the fair market value of the assets. For this reason, Pioneer Parent
and Pioneer USA believe that the merger value for each partnership is more
indicative of the fair market value of the assets of each partnership than the
net book value of the partnership's assets. See the supplemental information
table on the second page of the supplement for each partnership for the
partnership's merger value and its book value, in each case per $1,000 limited
partner investment. In all cases except Parker & Parsley 81-II, Ltd., the merger
value is higher than the book value. For Parker & Parsley 81-II, Ltd., the
merger value is lower than book value because of the long-lived nature of the
oil and gas properties owned by Parker & Parsley 81-II, Ltd. The merger value of
Parker & Parsley 81-II, Ltd. takes into account the discounting effect of owning
long-lived oil and gas reserves that is not reflected in a book value
computation for the partnership. Nonetheless, Pioneer USA has determined that
the merger transaction is fair to the limited partners of Parker & Parsley
81-II, Ltd. (1) for the reasons noted above and (2) because Pioneer Parent and
Pioneer USA believe that the five-year NYMEX futures prices used in the
calculation of the merger value for the partnership (A) provide a reasonable
benchmark on the outlook for energy prices, (B) are regularly used by financial
markets, industry participants, and lenders in evaluating transactions, and (C)
are higher than historic prices.



     Trading Price of Units. None of the partnership interests are traded on a
national stock exchange or in any other significant market. Although some
partnership interests are occasionally sold in private or an informal secondary
market for limited partner securities, Pioneer Parent and Pioneer USA believe
any market for the partnership interests is not reliable as an indicator of
value because any such market is highly illiquid and generally reflects an
illiquidity discount. As a result, Pioneer Parent and Pioneer USA did not base
the calculation of the merger value for any partnership on recent trading prices
of partnership interests in the partnership. See Table 15 of Appendix A for
historical information about recent trades of partnership interests in each
partnership.



     Repurchase Offers. Pioneer Parent and Pioneer USA did not base the
calculation of the merger value for any partnership on the price of recent
repurchase offers in the partnership. Most partnerships do not have a repurchase
offer obligation, so no repurchase price information was available for those
partnerships. Of the partnerships with a repurchase offer obligation, the most
recent repurchase offers will be based on December 31, 2000 oil and gas prices.
The merger value for each partnership with repurchase offer obligations is lower
than the 2001 repurchase offer price for the partnership because the repurchase
price was based on NYMEX oil and gas prices as of December 31, 2000, which were
$26.69 per Bbl of oil and $9.95 per Mcf of gas. Pioneer Parent and Pioneer USA
believe that the repurchase obligation is not an indicator of fair value because
it is calculated annually on December 31 using oil and gas prices for that
specific day. The value determined under the repurchase obligation does not
adequately reflect future demand and supply fundamentals which have historically
resulted in significant volatility to oil and gas prices. See "Risk Factors --
Risk Factors Relating to the Merger of Each Partnership -- Repurchase Offers in
2001 By Each of the Six Partnerships with a Repurchase Obligation were Higher
than the Merger Value for the Partnership" on page 19 of this document and Table
8 of Appendix A to this document for information on each partnership with
repurchase offer obligations.



     Timing of Pricing. Oil and gas prices have recovered from NYMEX oil and gas
prices of $12.00 per Bbl of oil and $2.00 per Mcf of gas as of December 31,
1998, to the five-year NYMEX futures prices for oil and gas as of March 30,
2001, set forth in the table on page 6 of this document. Pioneer Parent and
Pioneer USA used those recovered oil and gas prices to calculate the merger
value for each partnership. Future oil and gas prices could be higher or lower
than the prices on March 30, 2001 which were used in calculating the merger
value for each partnership. Significant increases in future prices would
increase cash available for distribution from each partnership and could, in
retrospect, suggest that the merger value for such partnership was low by
comparison. If those current prices were to continue to prevail in the future,
the merger value for each partnership would appear low by comparison. In
contrast, however, if those current prices decline in the future, the merger
value for each partnership would appear high by comparison.



                                      -46-
   57

                         THE MERGER OF EACH PARTNERSHIP

GENERAL


     Immediately before the effective time of the merger of each participating
partnership, the partnership agreement for the partnership will be amended by
the merger amendment to permit the merger of the partnership with and into us.
At the effective time of the merger of each participating partnership, the
partnership will be merged with and into us. We will be the surviving entity. In
addition, at the effective time of the merger of each participating partnership,
each of your partnership interests in the partnership will be converted into the
right to receive Pioneer Parent common stock.


LEGAL OPINION FOR LIMITED PARTNERS

     Each of the partnership agreements, except the partnership agreement for
Parker & Parsley Producing Properties 88-A, L.P., requires that special legal
counsel render an opinion on behalf of the limited partners of each partnership
to Pioneer USA that neither the grant nor the exercise of the right to approve
the merger of the partnership by its limited partners will adversely affect the
federal income tax classification of the partnership or any of its limited
partners. In addition, the partnership agreement for each of the following
partnerships requires an opinion that neither the grant nor exercise of such
right will result in the loss of any limited partner's limited liability:


                                                          
     Parker & Parsley 81-1, Ltd.                             Parker & Parsley Selected 85 Private Investment, Ltd.
     Parker & Parsley 81-II, Ltd.                            Parker & Parsley 86-A, Ltd.
     Parker & Parsley 82-I, Ltd.                             Parker & Parsley 86-B, Ltd.
     Parker & Parsley 82-II, Ltd.                            Parker & Parsley 86-C, Ltd.
     Parker & Parsley 82-III, Ltd.                           Parker & Parsley Private Investment 86, Ltd.
     Parker & Parsley 83-A, Ltd.                             Parker & Parsley 87-A Conv., Ltd.
     Parker & Parsley 83-B, Ltd.                             Parker & Parsley 87-A, Ltd.
     Parker & Parsley 84-A, Ltd.                             Parker & Parsley 87-B, Ltd.
     Parker & Parsley 85-A, Ltd.                             Parker & Parsley Producing Properties 87-A, Ltd.
     Parker & Parsley 85-B, Ltd.                             Parker & Parsley Producing Properties 87-B, Ltd.
     Parker & Parsley Private Investment 85-A, Ltd.


     For each of the partnerships, other than those listed below, the counsel
designated to render the opinion described above must be counsel other than
counsel to Pioneer USA or any partnership:


                                                          
     Parker & Parsley 88-A Conv., L.P.                       Parker & Parsley 90-A Conv., L.P.
     Parker & Parsley 88-A, L.P.                             Parker & Parsley 90-A, L.P.
     Parker & Parsley 88-B Conv., L.P.                       Parker & Parsley 90-B Conv., L.P.
     Parker & Parsley 88-B, L.P.                             Parker & Parsley 90-B, L.P.
     Parker & Parsley 88-C Conv., L.P.                       Parker & Parsley 90-C Conv., L.P.
     Parker & Parsley 88-C, L.P.                             Parker & Parsley 90-C, L.P.
     Parker & Parsley Private Investment 88, L.P.            Parker & Parsley Private Investment 90, L.P.
     Parker & Parsley 89-A Conv., L.P.                       Parker & Parsley 90 Spraberry Private Dev., L.P.
     Parker & Parsley 89-A, L.P.                             Parker & Parsley 91-A, L.P.
     Parker & Parsley 89-B Conv., L.P.                       Parker & Parsley 91-B, L.P.
     Parker & Parsley 89-B, L.P.
     Parker & Parsley Private Investment 89, L.P.



     In all cases, the designated counsel and the legal opinion must be approved
by the limited partners of each partnership.


     In all cases, Pioneer USA has retained             of Dallas, Texas for the
purpose of rendering the legal opinions described above on behalf of the limited
partners of each partnership to Pioneer USA.            is not affiliated to
Pioneer Parent, Pioneer USA or any of the partnerships. The merger proposals for
each partnership include an approval of that counsel and the form of its
opinion. See "The Special Meetings -- Time and Place; Purpose" on page 58 of
this document. A copy of the opinion is attached as an exhibit to the merger
proposals for each partnership.



                                      -47-
   58



DISTRIBUTION OF PIONEER PARENT COMMON STOCK



     Upon completion of the merger of each participating partnership, the
partners of the partnership will have no continuing interest in, or rights as
partners of, the partnership. The transfer books of each participating
partnership will be closed on the closing date of the merger of the partnership.
All partnership interests in each participating partnership will cease to be
outstanding, will automatically be cancelled and retired, and will cease to
exist. The certificates previously representing partnership interests in each
participating partnership held by record partners will represent only the right
to receive Pioneer Parent common stock.



     We intend to mail certificates representing Pioneer Parent common stock to
the partners of record of each participating partnership promptly following the
effectiveness of the merger of the partnership in payment of the merger value
for the partnership. Partners of each participating partnership will not be
required to surrender partnership interest certificates to receive the Pioneer
Parent common stock.


FRACTIONAL SHARES


     Pioneer Parent will not issue fractional shares to any limited partner upon
completion of the merger of any partnership. For each fractional share that
would otherwise be issued, Pioneer Parent will round any fractional shares of
Pioneer Parent common stock up to the nearest whole share.


MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES


     The following discussion describes the material federal income tax
consequences of a conversion of partnership interests into Pioneer Parent common
stock pursuant to the merger of each participating partnership. The federal tax
consequences of each merger will vary for each limited partner because of the
different circumstances of each participating partnership and the individual
federal income tax position of each limited partner.



     Except as otherwise indicated, statements of legal conclusion regarding tax
treatments, tax effects or tax consequences are the opinions of Vinson & Elkins
L.L.P, counsel for Pioneer Parent based upon current law. Future legislative,
judicial or administrative changes or interpretations could alter or modify the
following statements and conclusions, and any of these changes or
interpretations could be retroactive and could affect the tax consequences to
the limited partners of each partnership.


     The following discussion is not exhaustive of all possible tax
consequences. It does not address any state, local or foreign tax consequences,
nor does it discuss all of the aspects of federal income taxation that may be
relevant to specific partners in light of their particular circumstances. The
discussion below describes material federal income tax consequences applicable
to individuals who are citizens or residents of the United States, and therefore
has limited application to domestic corporations and persons subject to
specialized federal income tax treatment, such as foreign persons, tax-exempt
entities, regulated investment companies and insurance companies.


     A copy of the tax opinion of Vinson & Elkins has been filed as an exhibit
to the registration statement of which this document is a part. Vinson & Elkins'
tax opinion is based, in part, on various assumptions of fact and certificates.



     The following discussion does not address the particular facts and
circumstances of any particular limited partner. You are advised to consult your
own tax advisor to determine all of the relevant federal, state and local tax
consequences of each merger particular to you.


TAX CONSEQUENCES OF A CONVERSION OF PARTNERSHIP INTERESTS.


     o Generally. As more fully described below, if you own partnership
interests in a participating partnership, you will generally recognize an
aggregate amount of net gain or loss equal to the difference between (1) the
fair market value of Pioneer Parent common stock you receive in the merger of
that partnership and (2) your adjusted tax basis in your partnership interests
exclusive of any basis attributable to liabilities of the partnership
immediately prior to the merger. That net gain or loss may be comprised of
ordinary income or ordinary loss depending upon the extent of any recapture of
depletion or intangible drilling and development costs and any appreciation or
depreciation in the ordinary assets of the partnership. The recognition of
ordinary income will decrease the capital gain component or increase the capital
loss component of the net gain or loss otherwise recognizable as a consequence
of the merger.



     o Characterization of the Merger of Each Partnership. The merger of a
participating partnership into Pioneer USA should be treated for federal income
tax purposes as a sale by such partnership of its assets for Pioneer Parent
common stock followed by a distribution of the Pioneer Parent common stock
received in liquidation of the limited partnership interests. Under Section 613A
of the Internal Revenue Code, each of the partners of such partnership must:



                                      -48-
   59


          -    maintain the partner's share of the basis in the partnership's
               oil and gas properties at the partner level;

          -    adjust such basis for depletion deductions; and

          -    use such basis to calculate gain or loss at the partner level on
               any sale by the partnership of its oil and gas properties.

     Accordingly, each of the mergers should be generally treated for tax
computation purposes as:


          -    a taxable sale by you of your interest in a participating
               partnership's oil and gas properties for Pioneer Parent common
               stock and the assumption of liabilities; and



          -    a taxable sale of any remaining partnership assets by the
               participating partnership for Pioneer Parent common stock
               followed by a liquidation of the participating partnership.


     o Gain or Loss on Sale of Partnership Oil and Gas Properties. Upon the
deemed sale of a partnership's oil and gas properties in the merger of the
partnership, you will recognize gain or loss equal to the difference between:

          -    the portion of the partnership's "amount realized" on the sale of
               its oil and gas properties allocated to you; and

          -    your adjusted tax basis in the partnership oil and gas properties
               sold, which must be reduced to reflect depletion claimed during
               the current year in respect of production prior to the date of
               the merger.


     The amount realized will include the fair market value of Pioneer Parent
common stock received and the amount of any liability assumed by Pioneer USA in
connection with the merger of the partnership which is attributable to the
partnership's oil and gas properties. If gain is recognized on such sale, the
portion of the gain that is treated as recapture of intangible drilling and
development costs or depletion will be treated as ordinary income. See
"Recapture of Intangible Drilling and Development Costs" and "Recapture of
Depletion" below. The remainder of such gain generally will constitute "Section
1231 gain." If loss is recognized on such sale, such loss generally will
constitute "Section 1231 loss." See "Section 1231 Gains and Losses" below. You
must take into account your share of the portion of the gain that constitutes
recapture income, if any, as ordinary income and must aggregate your share of
the Section 1231 gains and losses along with the Section 1231 gains and losses
you realize from other sources.


     o Other Gain or Loss. You will also recognize your allocable share of the
partnership's gain or loss, if any, on the deemed sale of its assets other than
oil and gas properties. Such gain or loss will be equal to the difference
between the amount realized by the partnership on the sale of such assets and
the partnership's adjusted tax basis in such assets. Such gain or loss will be
capital or ordinary depending on the nature of the assets sold.


     Finally, in the event that the fair market value of Pioneer Parent common
stock you receive in the merger of the partnership is more or less than the
adjusted tax basis in your partnership interests, as adjusted to reflect gains
and losses described in the two preceding paragraphs as well as the effects of
the partnership's current year activities, then upon the deemed liquidation of a
partnership, you will recognize capital gain or loss equal to the difference
between such amounts. See "Tax Consequences of Partnership Operations" below.



     You will be provided with information necessary to make the calculations
under Section 613A of the Internal Revenue Code described above for purposes of
filing your own federal income tax return. In order to simplify your federal
income tax reporting, this information will include a calculation of the amount
and character of your gain on the deemed sale of the partnership's oil and gas
properties based upon our estimates. You should verify the accuracy of these
calculations based upon your own records.


     o Section 1231 Gains and Losses. Generally, if the total amount of the
Section 1231 gains exceeds the total amount of Section 1231 losses, all such
gains and losses will be treated as capital gains and losses, and if the total
amount of the Section 1231 losses exceeds the total amount of the gains, all
such gains and losses will be treated as ordinary income and losses. However,
your net Section 1231 gains will be treated as ordinary income to the extent of
your net Section 1231 losses during the immediately preceding five years,
reduced by any amount of net Section 1231 losses that have been previously
"recaptured" by you pursuant to this rule.

     o Recapture of Intangible Drilling and Development Costs. Generally, all or
a portion of the amounts previously deducted for intangible drilling and
development costs for a property must be recaptured upon the disposition of such
property by treating the gain, if any, realized on such disposition as ordinary
income to the extent of such amounts. For a property placed in service prior to
1987, the potential recapture amount is equal to the excess of the aggregate
amounts previously deducted for intangible drilling and development costs for
such property over the amount by which the deduction for depletion for such
property would have been increased had the intangible drilling and development
costs been capitalized and recovered through depletion rather than deducted in
the year incurred. It


                                      -49-
   60


should be noted that, if percentage depletion, rather than cost depletion, has
been claimed for such property, the hypothetical capitalization of intangible
drilling and development costs may result in little or no increase in depletion
deductions and, as a consequence, most or all of the intangible drilling and
development costs for such property may be subject to recapture. For property
placed in service during 1987 or thereafter, the full amount of intangible
drilling and development costs previously deducted, unreduced by depletion, is
subject to recapture to the extent of any gain.

     o Recapture of Depletion. Upon the disposition of a property that was
placed in service during 1987 or thereafter, all amounts previously deducted for
depletion, whether cost depletion or percentage depletion, to the extent such
amounts reduced the basis in the property, must be recaptured by treating the
gain, if any, recognized on such disposition as ordinary income to the extent of
such amounts. No such recapture rule is applicable to a property placed in
service before 1987.


     o Tax Rates. The capital gains rate for individuals and other non-corporate
taxpayers is 20% if the capital asset has been held for more than one year at
the time of consummation of the merger of each partnership. Corporate taxpayers
are taxed at a maximum marginal rate of 35% for both capital gains and ordinary
income. The maximum marginal federal income tax rate for ordinary income of
individuals and other non-corporate taxpayers is currently 39.1%. Capital losses
are deductible only to the extent of capital gains, except that, subject to the
passive activity loss limitation discussed below, non-corporate taxpayers may
deduct up to $3,000 of capital losses in excess of the amount of their capital
gains against ordinary income. Excess capital losses generally can be carried
forward to succeeding years. A corporation is permitted to carry back excess
capital losses to the three preceding years, provided the carryback does not
increase or produce a net operating loss for any of those years. A corporation's
carryforward period is five years and a non-corporate taxpayer can carry such
losses forward indefinitely.


     o Passive Activity Loss Limitation. Under Section 469 of the Internal
Revenue Code, any losses from any participating partnership that have been
suspended under the passive loss rules will become fully deductible as a result
of the merger of any such partnership.


FIRPTA Withholding. Gain recognized by a foreign limited partner on the sale by
a participating partnership which is effectively connected with the conduct of a
U.S. trade or business of its assets pursuant to the merger of the partnership
will be subject to federal income tax. Gain recognized on the sale of U.S. real
property, including a participating partnership's oil and gas properties, is
treated as effectively connected with the conduct of a U.S. trade or business
for this purpose. Under Internal Revenue Code Section 1446, a participating
partnership in which an interest is held by a foreign person generally is
required to deduct and withhold a tax equal to the highest marginal federal
income tax rate applicable to the partner multiplied by such partner's allocable
share of effectively connected income. In order to comply with this requirement,
each participating partnership will withhold the prescribed percentage of the
effectively connected income allocated to you unless you properly complete and
sign a certification of non-foreign status certifying your taxpayer
identification number and address, and that you are not a foreign person.
Amounts withheld will be creditable against a limited partner's federal income
tax liability and, if in excess thereof, a refund may be obtained from the
Internal Revenue Service by filing a U.S. income tax return.


Tax Consequences of Partnership Operations. The federal income tax consequences
of the merger of each partnership, described above, are in addition to the tax
consequences of a participating partnership for the taxable year ending on the
closing date of the merger of the partnership. You must include your allocable
share of a participating partnership's items of income, gain, loss, deduction
and credit for that taxable year, including your allocable share through the
closing date of the merger of the partnership, on your federal income tax return
for that taxable year. That information will be provided to you on a Schedule
K-1 as required by tax law. The results of partnership operations for such
period will impact your tax basis in a participating partnership, and your
computation of gain or loss resulting from the merger of the partnership.

ACCOUNTING TREATMENT

     The merger of each participating partnership will be accounted for as a
purchase under generally accepted accounting principles. Under those rules,
Pioneer USA will record the assets and liabilities of each participating
partnership on its books at its estimated fair market value.


EFFECT OF DEBT OWED BY A LIMITED PARTNER TO PIONEER USA ON AMOUNT OF PIONEER
PARENT COMMON STOCK TO BE RECEIVED BY THE LIMITED PARTNER



     If a limited partner is indebted to Pioneer USA for any portion of the
limited partner's original investment in the partnership, Pioneer USA plans to
apply the Pioneer Parent common stock that would otherwise be distributed to the
limited partner upon completion of the merger of the partnership against that
limited partner's indebtedness. If a limited partner's indebtedness to Pioneer
USA is less than the merger value allocated to limited partnership interests
held by the limited partner, the limited partner will receive Pioneer Parent
common stock equal to the amount by which such merger value exceeds such
indebtedness. If a limited partner's indebtedness to Pioneer USA is greater



                                      -50-
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than the merger value allocated to the limited partnership interests held by the
limited partner, Pioneer USA may collect the deficiency from the limited
partner.

EFFECT OF MERGER OF EACH PARTNERSHIP ON LIMITED PARTNERS WHO DO NOT VOTE IN
FAVOR OF THE MERGER; NO APPRAISAL OR DISSENTERS' RIGHTS


     You will be bound by the merger of each partnership in which you own an
interest if the limited partners in the partnership vote a majority, or 66-2/3%
for Parker & Parsley 91-A, L.P. and Parker & Parsley 91-B, L.P., of their
partnership interests in favor of the merger, even if you vote against the
merger or do not vote. If the merger of the partnership occurs, you will be
entitled to receive only Pioneer Parent common stock based on the merger value
of your partnership interests in the partnership. Under the laws of the State of
Delaware and the State of Texas, which are the states of formation of the
partnerships, you are not entitled to appraisal or dissenters' rights with
respect to the merger of any partnership.


FUTURE OF NONPARTICIPATING PARTNERSHIPS


     If the limited partners of a partnership do not approve the merger of that
partnership, the partnership will remain in existence. Each nonparticipating
partnership will continue to operate as a separate legal entity with its own
assets and liabilities. There will be no immediate change in its business
objectives, and Pioneer USA plans to continue to manage and operate each
nonparticipating partnership in accordance with the terms of its current
partnership agreement. A limited partner in a nonparticipating partnership will
retain the rights, privileges and obligations that the limited partner currently
has pursuant to the partnership agreement of the nonparticipating partnership.
At about the same time that Pioneer USA mails certificates for Pioneer Parent
common stock to the partners of each participating partnership in payment of the
merger value for the partnership, Pioneer USA will mail any cash distributions
that were delayed for administrative purposes prior to the completion of the
merger of each participating partnership to the partners of each
nonparticipating partnership.



     Pioneer USA's board of directors will determine each nonparticipating
partnership's business plan. In addition, the board of directors of each of
Pioneer Parent and Pioneer USA will decide what, if any, actions they will take
with respect to each nonparticipating partnership. Potential activities may
include a tender offer for partnership interests of limited partners or a
proposal to acquire the assets of, or merge with, one or more of the
nonparticipating partnerships. Such proposals may be on terms similar to or
different from those of the merger of each partnership described in this
document.



     Pioneer USA plans to continue to manage each nonparticipating partnership
until such partnership is dissolved or Pioneer USA is replaced as the general
partner of such partnership. The replacement of Pioneer USA as general partner
would require compliance with the partnership agreement of such nonparticipating
partnership, including the requisite vote of the limited partners thereof. A
nonparticipating partnership may be dissolved in the future in accordance with
its partnership agreement if Pioneer USA or any substituted general partner
withdraws from the nonparticipating partnership, or in some cases, otherwise
elects to dissolve that partnership. Pioneer USA might withdraw from, or
otherwise elect to dissolve, a nonparticipating partnership if Pioneer USA
determines that the nonparticipating partnership's continued operation is
uneconomical or its dissolution and liquidation are in the best interests of the
partners of that partnership. Upon dissolution, the nonparticipating
partnership's assets may be sold for cash or securities, which may be more or
less than the merger value assigned to that partnership, or distributed in kind
to the partners of the nonparticipating partnership. Any such sale may be to
Pioneer Parent or an affiliate of Pioneer Parent and may involve cash or
securities of Pioneer Parent.


NONMANAGING GENERAL PARTNERS OF SOME PARTNERSHIPS


     Eight of the partnerships described in this document have two general
partners. In those eight partnerships, Pioneer USA is the managing general
partner. The second general partner in those partnerships is a parallel
partnership whose limited partners are former affiliates of Pioneer Parent's
predecessors. The names of the eight partnerships and the names of the
nonmanaging general partner in each of those partnerships are:





             PARTNERSHIP                    NONMANAGING GENERAL PARTNER
             -----------                    ---------------------------
                                         
     Parker & Parsley 81-I, Ltd.             P&P Employees 81-I, Ltd.
     Parker & Parsley 81-II, Ltd.            P&P Employees 81-II, Ltd.
     Parker & Parsley 82-I, Ltd.             P&P Employees 82-I, Ltd.
     Parker & Parsley 82-II, Ltd.            P&P Employees 82-II, Ltd.
     Parker & Parsley 82-III, Ltd.           P&P Employees 82-III, Ltd.
     Parker & Parsley 83-A, Ltd.             P&P Employees 83-A, Ltd.
     Parker & Parsley 83-B, Ltd.             P&P Employees 83-B, Ltd.
     Parker & Parsley 84-A, Ltd.             P&P Employees 84-A, Ltd.




                                      -51-
   62


     Pioneer USA is the sole general partner of each of the nonmanaging general
partners. In that capacity, Pioneer USA has authority:

     o    to cause the nonmanaging general partner to perform its obligations
          relating to the partnership described above; and

     o    to exercise on behalf of the nonmanaging general partner all of the
          rights and elections granted to the nonmanaging general partner by the
          partnership described above.


     None of the nonmanaging general partners has the right to vote on the
merger of any partnership. However, Pioneer USA, as the general partner of each
nonmanaging general partner, has approved the merger of each partnership and the
distribution of this document to the limited partners of each partnership and to
the unaffiliated limited partners of each nonmanaging general partner, if any,
of each partnership. The merger value attributable to the unaffiliated limited
partners of the nonmanaging general partners is $199,780, consisting of
approximately 11,099 shares of Pioneer Parent common stock in the aggregate.
Pioneer USA will not receive any Pioneer Parent common stock in any merger for
its partnership interests in any nonmanaging general partner.


THIRD PARTY OFFERS


     Pioneer USA will consider offers from third parties to purchase any
partnership or its assets. Those who wish to make an offer for any partnership
or its assets must demonstrate to Pioneer USA's reasonable satisfaction their
financial ability and willingness to complete such a transaction. Before
reviewing non-public information about a partnership, a third party will need to
enter into a customary confidentiality agreement. Offers should be at prices and
on terms that are fair to the partners of the partnership for which the offer is
being made and more favorable to the unaffiliated limited partners than the
prices and terms proposed for the merger of that partnership in this document.
Pioneer Parent reserves the right to match or top any such offer. In addition,
any such offer would be subject to Pioneer USA's right to continue operation of
the properties. Since first announcing our willingness to consider third party
offers in September 1999, Pioneer USA has not received any third party offer for
any partnership or its assets. Persons desiring to make an offer for any
partnership should contact Timothy L. Dove or Mark L. Withrow, Board of
Directors, Pioneer Natural Resources USA, Inc., 1400 Williams Square West, 5205
North O'Connor Boulevard, Irving, Texas 75039 by August 1, 2001.


MERGER AMENDMENT


     In order to complete the merger of each partnership, the partnership
agreement for the partnership requires an amendment to add a provision
permitting the merger of the partnership with and into Pioneer USA. See the
merger proposals, which include the merger amendment, set forth in Appendix E to
this document. At the special meeting for each partnership, the limited partners
of the partnership will vote upon the merger amendment, which, if approved, will
be effective immediately prior to the effectiveness of the merger of the
partnership.


TERMINATION OF REGISTRATION AND REPORTING REQUIREMENTS

     As a result of the merger of each participating partnership, the
partnership interests in the partnership, as well as the partnership itself,
will cease to exist. Twenty-five of the partnerships described in this document
have registered their partnership interests under, or are otherwise subject to
the informational requirements of, the Securities Exchange Act of 1934. See
"Where You Can Find More Information" for a list of those partnerships. Upon the
completion of the merger of each reporting partnership, Pioneer USA intends to
terminate:

     o    registration of the partnership interests of the partnership under the
          Securities Exchange Act of 1934; and

     o    the partnership's obligations to file reports and other information
          under the Securities Exchange Act of 1934.

     Pioneer USA plans to cause each nonparticipating partnership that is also a
reporting partnership to continue to file reports and other information under
the Securities Exchange Act of 1934. However, Pioneer USA's board of directors
could determine in the future to cause each such partnership to terminate its
reporting obligations as permitted by federal securities laws.

     The advantages of remaining registered, or remaining obligated to file
reports, under the Securities Exchange Act of 1934 include the informational and
reporting requirements under that act, including requirements related to tender
offers, proxy solicitation and consents and insiders' transactions in
partnership interests. Those reporting requirements may provide limited partners
with more detailed information on a more frequent basis than might otherwise be
required under the partnership agreement for the partnership. In addition, a
partnership's filings under the Securities Exchange Act of 1934 are available to
the public over the Internet at the SEC's web site at http://www.sec.gov and are
also available at the SEC's public reference rooms in Washington, D.C., New
York, New York and Chicago, Illinois.


                                      -52-
   63


     The disadvantages of remaining registered, or remaining obligated to file
reports, include the partnership's cost to prepare and distribute the various
reports and other information required under the Securities Exchange Act of
1934. Deregistering the partnership interests of a nonparticipating partnership
or otherwise terminating its filing and reporting obligations could reduce that
partnership's general and administrative expenses because the reporting
obligations of the partnership under its partnership agreement require annual
and semi-annual reports, but not quarterly reports.

ELIMINATION OF A FAIRNESS OPINION REQUIREMENT THAT WOULD OTHERWISE BENEFIT
PIONEER USA

     Pioneer USA, as the sole general partner of each of Parker & Parsley 91-A,
L.P. and Parker & Parsley 91-B, L.P., is entitled to receive an opinion as to
the fairness of the proposed merger transaction to Pioneer USA in its capacity
as sole general partner of each of those partnerships. However, since Pioneer
Parent and Pioneer USA are the parties making the offer for the proposed merger
transaction, Pioneer USA will not seek such fairness opinion. In addition,
Pioneer USA, as the sole general partner of each of those two partnerships, is
entitled to amend, and Pioneer USA will amend, the partnership agreement for the
partnership to eliminate the requirement for such fairness opinion for Pioneer
USA in connection with the proposed merger of the partnership.


PAYMENT OF EXPENSES AND FEES



     Pioneer Parent and Pioneer USA estimate that the aggregate expenses and
fees of the mergers of all of the partnerships will be as follows:




                                                                   
Filing fee with SEC.................................................. $   20,500
Legal fees...........................................................    350,000
Accounting fees......................................................    100,000
Financial advisor fees...............................................    350,000
Independent petroleum consultant fees................................     50,000
Printing and mailing fees............................................    850,000
Information agent fees and solicitation and tabulation expenses......    225,000
Miscellaneous........................................................     54,500
                                                                      ----------
    Total expenses................................................... $2,000,000
                                                                      ==========




     Each participating partnership will pay its pro rata share, based on its
reserve value, of the aggregate estimated expenses and fees of the mergers of
all of the partnerships. Each nonparticipating partnership will pay a portion of
the aggregate estimated expenses and fees of the mergers otherwise allocable to
such nonparticipating partnership based on a fraction, the numerator of which is
the percentage of the partnership's limited partnership interests that are voted
in favor of the merger proposals and the denominator of which is the percentage
of the partnership's limited partnership interests for which votes are cast.
Pioneer Parent has agreed to pay (1) the remainder of the estimated expenses and
fees otherwise allocable to such nonparticipating partnership, (2) any expenses
and fees actually incurred in excess of $2.0 million, and (3) if Pioneer Parent
terminates or abandons the merger as to any partnership, any expenses or fees
allocated to that partnership. Pioneer Parent and Pioneer USA have reduced the
net working capital component of each partnership's merger value by that
partnership's pro rata share of the estimated expenses and fees.



                                      -53-
   64


                              THE MERGER AGREEMENT


     The following describes the material terms of the merger agreement. Pioneer
Parent and Pioneer USA expect to sign the merger agreement as soon as the
Securities and Exchange Commission declares effective under the Securities Act
of 1933 the registration statement that includes this document. The full text of
the form of the merger agreement is attached as Appendix F to this document and
is incorporated by reference in this document. We encourage you to read the
entire merger agreement.


STRUCTURE; EFFECTIVE TIME

     The merger agreement provides for the merger of each participating
partnership with and into Pioneer USA, with Pioneer USA surviving each merger.
Each merger will become effective at the time of the filing of the certificate
of merger for each participating partnership with the Secretary of State of the
State of Delaware and, for each participating partnership formed in Texas, with
the Secretary of State of the State of Texas. Each certificate of merger is
expected to be filed as soon as practicable after the last condition precedent
to the related merger set forth in the merger agreement has been satisfied or
waived. We estimate that the closing of the merger of each partnership will be
in the third quarter of 2001.


EFFECT OF THE MERGER OF EACH PARTNERSHIP


     As a result of the merger of each participating partnership, the partners
in the partnership will have no continuing interest in that partnership.
Following the merger of each participating partnership, there will be no trading
market for the partnership interests in, and no further distributions paid to
the former partners of, the partnership. In addition, following the consummation
of the merger of each participating partnership that is also a reporting
partnership, the registration of any partnership interests in the partnership
under the Securities Exchange Act of 1934 will be terminated.


CONDUCT OF BUSINESS PRIOR TO THE MERGER OF EACH PARTNERSHIP


     From the date of the merger agreement until the effective time of the
merger of each partnership, each partnership is required:

     o    to conduct its business only in the ordinary course consistent with
          past practice; and

     o    to use its reasonable best efforts:

          -    to preserve intact its business organization;

          -    to keep available the services of its officers, employees and
               consultants; and

          -    to preserve its relationships with customers, suppliers and other
               persons with which it has significant business dealings.


     Pioneer USA has suspended cash distributions to the partners of each
partnership until after the effective time of the merger of the partnership.
Partners of each nonparticipating partnership will receive cash distributions
that are delayed for administrative purposes at about the same time Pioneer USA
mails certificates for Pioneer Parent common stock to the partners of each
participating partnership in payment of merger value for each partnership.


OTHER AGREEMENTS

     Special Meetings; Proxies. Pioneer USA has agreed to cause the special
meeting of the limited partners of each partnership to be duly called and held
as soon as reasonably practicable for the purpose of voting on the approval and
adoption of the merger proposals for the partnership. Pioneer USA has also
agreed to use its reasonable best efforts to solicit from the limited partners
of each partnership proxies in favor of the merger proposals and to take all
other action necessary or advisable to secure any vote or consent of the limited
partners of the partnership required by the partnership agreement of the
partnership or the merger agreement or by law in connection with the merger of
the partnership.

     Reasonable Commercial Efforts. Each party has agreed to use all reasonable
commercial efforts:

     o    to obtain in a timely manner all necessary waivers, consents and
          approvals and to effect all necessary registrations and filings; and

     o    to take, or cause to be taken, all actions and to do, or cause to be
          done, all things necessary, proper or advisable under applicable laws
          and regulations to consummate as promptly as practicable the
          transactions contemplated by the merger agreement.


                                      -54-
   65


REPRESENTATIONS AND WARRANTIES OF PIONEER PARENT, PIONEER USA AND EACH
PARTNERSHIP


     The merger agreement contains substantially reciprocal representations and
warranties of Pioneer Parent, Pioneer USA and each of the partnerships,
including the following matters:


     o    due organization or formation, standing, corporate or partnership
          power and qualification;

     o    absence of any conflict, breach, notice requirement or default under
          organizational documents and material agreements as a result of each
          contemplated merger;

     o    authority to enter into and the validity and enforceability of the
          merger agreement;

     o    absence of any material adverse change since March 31, 2001; and

     o    accuracy of information.

     In addition, the merger agreement contains representations and warranties
by:

     o    each of the partnerships as to capitalization;


     o    each of Pioneer Parent and each reporting partnership, as to the
          absence in its reports filed with the SEC of any untrue statement of a
          material fact or any omission to state a material fact necessary to
          make the statements in such reports not misleading;



     o    each of Pioneer Parent and each partnership, that its financial
          statements have been prepared in accordance with generally accepted
          accounting principles applied on a consistent basis and fairly present
          its financial condition and results of operations; and


     o    Pioneer USA as to its capacity as the managing or sole general partner
          of each partnership and as the sole general partner of each
          nonmanaging general partner.

CONDITIONS TO THE MERGER OF EACH PARTNERSHIP


     Conditions to the Obligations of Each Party. The obligations of Pioneer
Parent, Pioneer USA and each partnership to complete the merger of the
partnership are dependent on the satisfaction of the following conditions:


     o    the merger agreement shall have been approved by the requisite vote of
          the limited partners of the partnership entitled to vote at the
          partnership's special meeting;

     o    Pioneer USA shall have received the fairness opinion from Stanger
          that, as of the date of that opinion, that the merger value for each
          partnership and the allocation of the merger value of the partnership
          (1) to the limited partners of the partnership as a group, (2) to the
          general partners of the partnership as a group, (3) to Pioneer USA as
          the managing or sole general partner of the partnership, (4) to the
          unaffiliated limited partners of the partnership as a group and (5) to
          the unaffiliated limited partners of the nonmanaging general partner,
          if any, of the partnership as a group, is fair to the unaffiliated
          limited partners of the partnership and the unaffiliated limited
          partners of the nonmanaging general partner, if any, of the
          partnership, from a financial point of view;

     o    Pioneer USA shall have received the opinion of counsel to the limited
          partners of each partnership that (1) neither the grant nor the
          exercise of the right to approve the merger of the partnership by its
          limited partners will adversely affect the federal income tax
          classification of the partnership or any of its limited partners and
          (2) neither the grant nor exercise of such right will result in the
          loss of any limited partner's limited liability;

     o    the absence of any law, regulation, judgment, injunction, order or
          decree that would prohibit the consummation of any merger;

     o    the absence of any pending suit, action or proceeding challenging the
          legality or any aspect of the merger of any partnership or the
          transactions related to the merger;


     o    the authorization for listing on the New York Stock Exchange and the
          Toronto Stock Exchange upon official issuance of notice shall have
          been received for the shares of Pioneer Parent common stock to be
          issued upon the merger of each partnership;



                                      -55-
   66


     o    all material filings and registrations with, and notifications to,
          third parties shall have been made and all material approvals and
          consents of third parties shall have been received; and

     o    the absence of any opinion of counsel that the exercise by the limited
          partners of each partnership of the right to approve the merger of the
          partnership is not permitted by state law.


     Conditions to the Obligations of Pioneer Parent. The obligations of Pioneer
Parent to complete the merger of each partnership are further subject to the
satisfaction of the following conditions:


     o    each of Pioneer USA and each partnership having performed in all
          material respects its agreements contained in the merger agreement;
          and

     o    the representations and warranties of Pioneer USA and each partnership
          being true and correct in all material respects at the closing date of
          the merger of the partnership as if made at that time unless they
          relate to another specified time.

     Conditions to the Obligations of Pioneer USA and Each Partnership. The
obligations of Pioneer USA and each partnership to complete the merger of the
partnership are further subject to the satisfaction of the following conditions:


     o    Pioneer Parent having performed in all material respects its
          agreements contained in the merger agreement; and



     o    the representations and warranties of Pioneer Parent being true and
          correct in all material respects at the closing date of the merger of
          the partnership as if made at that time unless they relate to another
          specified time.


TERMINATION OF THE MERGER AGREEMENT AND THE MERGER OF ANY PARTNERSHIP

     The merger agreement may be terminated and the merger of any partnership
abandoned at any time prior to the effective time, whether before or after
approval by the limited partners:

     o    by the mutual written consent of the parties;

     o    by any party, if:

          -    any applicable law, rule or regulation makes consummation of any
               merger illegal or otherwise prohibited or any final and
               non-appealable judgment, injunction, order or decree enjoining
               any party from consummating any merger is entered;

          -    the requisite limited partner approval for a partnership is not
               obtained by a vote at the special meeting for the partnership or
               at any adjournment or postponement of the special meeting; or


          -    any suit, action or proceeding is filed against Pioneer Parent,
               Pioneer USA, any partnership or any officer, director or
               affiliate of Pioneer Parent or Pioneer USA challenging the
               legality or any aspect of the merger of any partnership or the
               transactions related to the merger;



     o    by Pioneer Parent, if Pioneer USA or any partnership is in material
          breach of the merger agreement;



     o    by Pioneer USA or any partnership as to that partnership's merger, if
          Pioneer Parent is in material breach of the merger agreement;


     o    by Pioneer USA, if Pioneer USA's board of directors determines that
          termination of the merger agreement is required in order for the board
          to comply with its fiduciary duties; or


     o    by Pioneer Parent, if there shall have occurred any event,
          circumstance, condition, development or occurrence causing, resulting
          in or having, or reasonably expected to cause, result in or have, a
          material adverse effect (1) on any partnership's business, operations,
          properties, taken as a whole, condition, financial or otherwise,
          results of operations, assets, taken as a whole, liabilities, cash
          flows or prospects, (2) on market prices for oil and gas prevailing
          generally in the oil and gas industry since the date of determination
          of the oil and gas commodity prices used in the determination of the
          merger value for each partnership, (3) on the price of Pioneer Parent
          common stock or (4) on the oil and gas industry generally.



     If the merger agreement is validly terminated or the merger of any
partnership is abandoned, none of Pioneer Parent, Pioneer USA nor any such
partnership shall have any liabilities or obligations to the other parties based
on the merger agreement or such merger except:



                                      -56-
   67



     o    Pioneer Parent will pay all expenses and fees of each partnership in
          connection with the merger of that partnership incurred before the
          termination of the merger agreement or abandonment of the merger of
          the partnership; and


     o    a party will be liable if that party is in breach of the merger
          agreement.

AMENDMENTS; WAIVERS


     Any provision of the merger agreement may be amended prior to the effective
time if the amendment is in writing and signed by Pioneer Parent and Pioneer
USA; provided, that after the approval of the merger proposals by the limited
partners of each partnership, no amendment shall, without the further approval
of the limited partners of each partnership:


     o    adversely change the type or amount of, or the method of determining,
          the consideration to be received in exchange for any partnership
          interests in the partnership; or

     o    materially and adversely affect the rights of the limited partners of
          the partnership, other than a termination of the merger agreement or
          abandonment of the merger of the partnership.

     Prior to the effective time, the parties may:

     o    extend the time for the performance of any of the obligations of the
          parties;

     o    waive any inaccuracies in the representations and warranties in the
          merger agreement or in a document delivered pursuant to the merger
          agreement; and

     o    waive compliance with any agreement or condition in the merger
          agreement.

Any such extension or waiver will be valid only if it is in writing and signed
by the party against whom the extension or waiver is to be effective.


                                      -57-
   68

                              THE SPECIAL MEETINGS

TIME AND PLACE; PURPOSE

     The special meeting of the limited partners of each partnership will be
held on         , 2001, at 10:00 a.m., at the Dallas Marriott Las Colinas Hotel,
Irving, Texas 75039. The purpose of each special meeting, and any adjournment or
postponement of the special meeting for each partnership, is for the limited
partners of each partnership to consider and vote on the following matters:


     o A proposal to approve an Agreement and Plan of Merger dated as of       ,
2001, among Pioneer Parent, Pioneer USA and each of the partnerships. Each
participating partnership will merge with and into Pioneer USA, with Pioneer USA
surviving the merger. Each partnership interest of a participating partnership
will be converted into Pioneer Parent common stock. The number of shares of
common stock Pioneer Parent will offer for all partnership interests of a
participating partnership will be based on (1) the participating partnership's
merger value and (2) the average closing price of the Pioneer Parent common
stock, as reported by the New York Stock Exchange, for the ten trading days
ending three business days before the initial date of the special meeting for
the partnership. The merger value for a participating partnership is equal to
the sum of the present value of estimated future net revenues from the
partnership's estimated oil and gas reserves and its net working capital, in
each case as of March 31, 2001, less its pro rata share, based on its reserve
value, of the estimated expenses and fees of the mergers of all of the
partnerships and less the cash distribution to be mailed on or about July 12,
2001, by the partnership to its partners. For purposes of illustration in this
document, we have calculated the number of shares to be issued based on an
assumed average closing price of $18.00 per share of Pioneer Parent common
stock. Prior to the date of the special meeting for each partnership, we will
update the number of shares to be issued using the actual average closing price
of Pioneer Parent common stock for the ten trading days ending three business
days before the initial date of the special meeting. The Pioneer Parent common
stock will be allocated among the partners based on the liquidation provisions
of each partnership agreement. Pioneer Parent will not issue fractional shares
to any limited partner upon completion of the merger of any partnership.
Instead, Pioneer Parent will round any fractional shares of Pioneer Parent
common stock up to the nearest whole share. Pioneer USA will not receive any
Pioneer Parent common stock for its partnership interests in the participating
partnerships.


     o A proposal to amend the partnership agreement of each partnership to
permit the partnership's merger with Pioneer USA. If the amendment is not
approved, that partnership cannot merge into Pioneer USA even if the partners of
that partnership approve the merger agreement.

     o A proposal (A) to approve the opinion issued to Pioneer USA by
on behalf of the limited partners of each partnership that neither the grant nor
the exercise of the right to approve the merger of the partnership by its
limited partners (1) will result in the loss of any limited partner's limited
liability or (2) will adversely affect the federal income tax classification of
the partnership or any of its limited partners and (B) to approve the selection
of              as special legal counsel for the limited partners of each
partnership to render such legal opinion.




     The Delaware Revised Uniform Limited Partnership Act and the Texas Revised
Limited Partnership Act require limited partner approval and adoption of the
merger agreement and the merger amendment. Generally, the partnership agreement
of each partnership requires that special legal counsel for the limited partners
render its legal opinion related to the limited partners' approval of the merger
of that partnership. See "The Merger of Each Partnership -- Legal Opinion for
Limited Partners" on page 46 of this document.


     PIONEER USA'S BOARD OF DIRECTORS UNANIMOUSLY DETERMINED THAT THE MERGER OF
EACH PARTNERSHIP IS ADVISABLE, FAIR TO THE UNAFFILIATED LIMITED PARTNERS OF THE
PARTNERSHIP, AND IN THEIR BEST INTERESTS. THE BOARD RECOMMENDS THAT THE
UNAFFILIATED LIMITED PARTNERS VOTE FOR THE MERGER PROPOSALS FOR EACH PARTNERSHIP
IN WHICH THEY OWN AN INTEREST. ALTHOUGH PIONEER USA'S BOARD OF DIRECTORS HAS
ATTEMPTED TO FULFILL ITS FIDUCIARY DUTIES TO THE LIMITED PARTNERS OF EACH
PARTNERSHIP, PIONEER USA'S BOARD OF DIRECTORS HAD CONFLICTING INTERESTS IN
EVALUATING EACH MERGER BECAUSE EACH MEMBER OF ITS BOARD OF DIRECTORS IS ALSO AN
OFFICER OF PIONEER PARENT.

RECORD DATE; VOTING RIGHTS AND PROXIES

     Only limited partners of record of each partnership at the close of
business on , 2001 are entitled to notice of and to vote at the special meeting
for the partnership in which they own partnership interests, or any adjournments
or postponements of such special meeting. Pioneer USA is entitled to vote
partnership interests it holds as a limited partner in all of the partnerships
except:

              Parker & Parsley 85-A, Ltd.
              Parker & Parsley 85-B, Ltd.
              Parker & Parsley Private Investment 85-A, Ltd.
              Parker & Parsley Selected 85 Private Investment, Ltd.
              Parker & Parsley Private Investment 86, Ltd.


                                      -58-
   69


              Parker & Parsley 91-A, L.P.
              Parker & Parsley 91-B, L.P.


Pioneer USA's affiliates are also entitled to vote partnership interests they
hold as limited partners in all but the seven partnerships listed above.
However, no affiliates of Pioneer USA own such interests. See "Ownership of
Partnership Interests" on page 64 of this document.



     Limited partners of record of each partnership are entitled to vote at the
partnership's special meeting based on the limited partners' respective
percentage of partnership interests in the partnership. Each limited partner
will receive a proxy card for all partnerships in which that limited partner
holds partnership interests. The proxy card will indicate the amount of Pioneer
Parent common stock offered with respect to such partnership interests in each
partnership. Although the number of shares of Pioneer Parent common stock
offered as shown on the proxy card may change, the value of Pioneer Parent
common stock offered as shown on the proxy card will not be adjusted. The
percentage of partnership interests that a limited partner holds in a
partnership is determined by comparing the amount of the limited partner's
initial investment, including any additional assessments, in the partnership to
the total investment of all partners, including any additional assessments, in
the partnership. The aggregate initial investment, including any additional
assessments, in each of the partnerships by the limited partners is set forth in
Table 1 of Appendix A.



     A limited partner of record may grant a proxy to vote for or against, or
may abstain from voting on, the merger proposals applicable to each of the
partnerships in which the limited partner holds partnership interests. To be
effective for purposes of granting a proxy to vote on the merger proposals
applicable to each partnership, a proxy card must be properly completed,
executed and delivered to Pioneer USA's information agent, in person or by mail,
telegraph, telex or facsimile before the special meeting for the partnership.
All partnership interests represented by properly executed proxies will, unless
these proxies have been previously revoked, be voted in accordance with the
instructions indicated in these proxies. If no instructions are indicated, the
partnership interests will be voted for approval and adoption of the merger
proposals. A properly executed proxy card for a partnership marked abstain is
counted as present for purposes of determining the presence or absence of a
quorum at the special meeting for the partnership, but will not be voted.
Accordingly, abstentions will have the same effect as a vote against the merger
proposals.



     Unrevoked proxies granted in the proxy cards for a partnership will be
voted at the special meeting for that partnership or at any adjournment or
postponement of the special meeting, if received by Pioneer USA's information
agent before the special meeting for the partnership. Proxies granted in the
proxy cards for a partnership will remain valid until the completion of the
special meeting for the partnership. Each partnership agreement requires that a
meeting be held within 60 days of the date of mailing of the notice of meeting.
None of the partnership agreements specifically addresses, and Pioneer USA has
not sought any opinions of counsel as to, whether proxies may be voted at a
meeting originally scheduled to be held within 60 days of the sending of the
notice and adjourned or postponed to a date more than 60 days after the date of
notice. Pioneer USA will not accept a vote of the limited partners of any
partnership in such circumstances unless it receives an opinion of counsel that
such a vote would be valid.


     The inspector of election appointed for the special meeting for each
partnership will tabulate the votes cast by proxy or in person at the special
meeting.


REVOCATION OF PROXIES


     You may revoke a proxy you have given at any time before that proxy is
voted at the special meeting for each partnership in which you own an interest
by:

     o    giving written notice of revocation to Pioneer USA;

     o    signing and returning a later dated proxy; or

     o    voting in person at the special meeting.

Your notice of revocation will not be effective until Pioneer USA receives it at
or before the special meeting for each partnership in which you own an interest.
Your presence at any such special meeting will not automatically revoke your
proxy in a proxy card. Revocation during any such special meeting will not
affect votes previously taken.

     You may deliver your written notice of revocation in person or by mail,
telegraph, telex, or facsimile. Any written notice of revocation must specify
your name and limited partner number as shown on your proxy card and the name of
the partnership to which your revocation relates.


                                      -59-
   70


SOLICITATION OF PROXIES


     We are soliciting your proxy pursuant to this document. The aggregate
estimated expenses and fees of the merger of each partnership that have been
allocated to each partnership include those incurred in connection with
solicitation of the enclosed proxy as described below.



     Pioneer USA has retained D.F. King & Co., Inc. to assist in the
solicitation of proxies from the limited partners of each partnership. The total
fees and expenses of D.F. King & Co., Inc. are estimated to aggregate $225,000
and have been allocated among the partnerships, on a pro rata basis, based on
each partnership's reserve value. In addition to solicitation by use of the
mail, proxies may be solicited by D.F. King & Co., Inc. and by directors,
officers and employees of Pioneer Parent and Pioneer USA in person or by
telephone, telegram, facsimile or e-mail. The directors, officers and employees
will not be additionally compensated, but may be reimbursed for out-of-pocket
expenses incurred in connection with the solicitation.



     Arrangements may also be made with other brokerage firms, banks,
custodians, nominees and fiduciaries for the forwarding of proxy solicitation
materials to owners of limited partnership interests held of record by those
persons. Each partnership will pay its pro rata share, based on its reserve
value, of those persons' reasonable expenses incurred in forwarding those
materials.



     Pioneer USA has also retained D.F. King & Co., Inc. to act as information
agent to perform consulting, administration and clerical work with respect to
the merger of each partnership. Pioneer USA has agreed to indemnify D.F. King &
Co., Inc. against certain liabilities, including liabilities under the federal
securities laws. D.F. King & Co., Inc. will also be responsible for the receipt
and tabulation of the proxy cards. The fees and expenses of D.F. King & Co.,
Inc. for its services as information agent and tabulator are included in the
aggregate amount set forth above.



     We intend to mail certificates representing shares of Pioneer Parent common
stock to the partners of record of each participating partnership promptly after
completing the merger of that partnership. Certificates representing partnership
interests will be automatically canceled, and you will not have to surrender
your certificates to receive the Pioneer Parent common stock.


QUORUM

     The presence in person or by properly executed proxy of a majority of
limited partnership interests entitled to vote in each partnership is necessary
to constitute a quorum at that partnership's special meeting.

     If a quorum is not present at any special meeting, the limited partners
entitled to vote who are present or represented by proxy at that special meeting
may adjourn or postpone that special meeting without notice until a quorum is
present. If a quorum is present at the adjourned or postponed meeting, any
business may be transacted that may have been transacted at the special meeting
had a quorum originally been present. If the adjournment or postponement is for
more than 30 days or if after the adjournment or postponement a new record date
is fixed for the adjourned or postponed meeting, a notice of the adjourned or
postponed meeting shall be given to each limited partner of record entitled to
vote at the adjourned or postponed meeting. The persons named as proxies intend
to vote in favor of any motion to adjourn or postpone the special meeting of any
partnership if, prior to the special meeting, they have not received sufficient
proxies to approve the merger of the partnership as described in this document.
This process will be repeated at any adjourned or postponed meeting until
sufficient proxies to vote in favor of the merger of the partnership have been
received or it appears that sufficient proxies will not be received.

REQUIRED VOTE; BROKER NON-VOTES


     Approval of the merger proposals for each partnership requires the
affirmative vote of the limited partners holding a majority of limited
partnership interests in that partnership, except that Parker & Parsley 91-A,
L.P. and Parker & Parsley 91-B, L.P. each require the favorable vote of the
holders, other than Pioneer USA, of 66-2/3% of its limited partnership interests
to approve those merger proposals. Pioneer USA is entitled to vote its
partnership interests on the merger proposals for each partnership except for
the partnerships set forth under "The Special Meetings -- Record Date; Voting
Rights and Proxies" on page 58. As a result, for each partnership in which
Pioneer USA is entitled to vote, approval of at least a majority, and for Parker
& Parsley 91-A, L.P. and Parker & Parsley 91-B, L.P., at least 66-2/3%, of the
unaffiliated limited partners is not required to approve the merger proposals.
However, for each partnership in which Pioneer Parent is not entitled to vote,
the approval of the unaffiliated limited partners is required to approve the
merger proposals.


     Brokers, if any, who hold partnership interests in street name for
customers have the authority to vote on "routine" proposals when they have not
received instructions from beneficial owners. However, these brokers are
precluded from exercising their voting discretion with respect to the approval
and adoption of non-routine matters such as the merger proposals and thus,
absent specific instructions from the beneficial owner of the partnership


                                      -60-
   71


interests, brokers are not empowered to vote the partnership interests with
respect to the merger proposals. These "broker non-votes" will have the effect
of a vote against the merger proposals.

PARTICIPATION BY ASSIGNEES


     Pioneer USA has the discretionary authority granted to it under each
partnership agreement to withhold its consent to the substitution of any
assignees as partners of the partnership. To facilitate the notification given
to limited partners of each partnership about the merger of the partnership,
Pioneer USA intends to exercise that authority and withhold its consent to the
substitution of any assignees as partners of the partnership from the date on
which this document is initially filed with the SEC until the earlier to occur
of the closing date of the merger of the partnership, or the termination or
abandonment of the transaction by Pioneer Parent and Pioneer USA.


SPECIAL REQUIREMENTS FOR SOME LIMITED PARTNERS

     Pioneer USA may require that any proxy card executed by an entity, such as
a trust, corporation, or partnership, be accompanied by evidence or an opinion
of counsel that such entity:

     o    has met all requirements of its governing instruments; and

     o    is authorized to execute and deliver the proxy card under the laws of
          the jurisdiction under which the entity was organized.

     Pioneer USA will require the named trustee and the beneficial owner of
trusts, including individual retirement accounts, to execute the proxy card. In
some cases, Pioneer USA may provide a limited partner with an envelope,
pre-addressed to his individual retirement account trustee, so that the limited
partner may forward his executed proxy card to the trustee for the trustee's
signature, if necessary, and subsequent delivery to Pioneer USA. Delivery of a
proxy card to the trustee, with or without the use of a pre-addressed envelope,
and delivery of a proxy card from the trustee to Pioneer USA are at the risk of
the limited partner.

VALIDITY OF PROXY CARDS

     A proxy card will not be valid unless it has been properly completed and
executed and timely delivered to Pioneer USA's information agent with all other
required documents. Pioneer USA will determine all questions as to the validity,
form, eligibility, time of receipt and acceptance of a proxy card and its
determination will be final and binding. Pioneer USA's interpretation of the
terms and conditions of the merger of each partnership, including the
instructions for the proxy card, will also be final and binding.

     A proxy card will not be valid until any irregularities have been cured or
waived. If Pioneer USA does not waive the irregularities, it will return the
defective proxy card to the limited partner as soon as practicable. Pioneer USA
is under no duty to give notification of defects in a proxy card and will incur
no liability if it fails to give such notification.

     Delivery of a proxy card is at the risk of the limited partner. A proxy
card will be effective for purposes of voting only when it is actually received
by Pioneer USA's information agent. To ensure receipt of the proxy card and all
other required documents, Pioneer USA suggests that limited partners use
overnight courier delivery or certified or registered mail, return receipt
requested.

LOCAL LAWS


     Proxy solicitations will not be made to, nor will proxy cards be accepted
from, limited partners of any partnership in any jurisdiction in which the
solicitations would not be in compliance with federal and state securities or
other laws. In any jurisdiction where securities laws require the proxy
solicitations to be made by a licensed broker or dealer, the proxy solicitations
are being made on behalf of Pioneer Parent and Pioneer USA by , which is
licensed under the laws of such jurisdiction.



                                      -61-
   72
           COMPARATIVE PER SHARE MARKET PRICE AND DIVIDEND INFORMATION


     The table below sets forth, for the calendar quarters indicated, the
reported high and low closing prices of Pioneer Parent common stock as reported
on the New York Stock Exchange Composite Transaction Tape, in each case based on
published financial sources. Pioneer Parent's board of directors did not declare
dividends to the holders of Pioneer Parent common stock during 1999, 2000 or the
three months ended March 31, 2001. The determination of the amount of future
cash dividends, if any, to be declared and paid is in the sole discretion of
Pioneer Parent's board of directors and will depend on the following factors:



     o    Pioneer Parent's financial condition;



     o    earnings and funds from operations;



     o    the level of Pioneer Parent's capital and exploration expenditures;



     o    dividend restrictions in Pioneer Parent's financing agreements;



     o    Pioneer Parent's future business prospects; and



     o    other matters that Pioneer Parent's board of directors deems relevant.


     None of the partnership interests of any partnership are traded on a
national stock exchange or in any other significant market. No liquid market
exists for interests in any of the partnerships. See Table 15 of Appendix A for
historical information about recent trades per $1,000 limited partner investment
in each partnership for the three months ended March 31, 2001 and the years
ended December 31, 2000 and 1999. The average quarterly cash distributions per
$1,000 limited partner investment in each partnership for 1999, 2000 and the
year-to-date in 2001 are set forth in Table 7 of Appendix A.


     On April 16, 2001, the last full trading day prior to the announcement of
the proposed merger of each partnership, Pioneer Parent common stock closed at
$17.27 per share. On , 2001, Pioneer Parent common stock closed at $ per share.




                            PIONEER PARENT COMMON
                            ---------------------
                                     STOCK
                                     -----
                                 MARKET PRICE
                                 ------------
                               HIGH        LOW
                              ------      ------
                                    
2001
     First quarter            $20.24      $15.45

2000
     Fourth quarter            20.63       12.44
     Third quarter             16.06       10.63
     Second quarter            15.63        9.00
     First quarter             10.75        6.75

1999
     Fourth quarter            11.50        7.63
     Third quarter             12.81        9.38
     Second quarter            13.19        7.06
     First quarter              9.75        5.00


     We urge the limited partners of each partnership to obtain current market
quotations prior to making any decision with respect to the merger of the
partnership.


                                      -62-
   73


                    INTERESTS OF PIONEER PARENT, PIONEER USA
                        AND THEIR DIRECTORS AND OFFICERS



     A number of conflicts of interest are inherent in the relationships among
each partnership, Pioneer Parent, Pioneer USA and their respective directors and
officers.


CONFLICTING DUTIES OF PIONEER USA, INDIVIDUALLY AND AS GENERAL PARTNER


     Pioneer USA, as general partner of each partnership, has a duty to manage
each partnership in the best interests of the limited partners. Pioneer USA also
has a duty to operate its business for the benefit of its sole stockholder,
Pioneer Parent. Consequently, Pioneer USA's duties to the limited partners of
each partnership may conflict with its duties to Pioneer Parent.



     The members of the board of directors of Pioneer USA have a duty to cause
Pioneer USA to manage each partnership in the best interests of the limited
partners. All members of the board of directors of Pioneer USA are officers of
Pioneer Parent and Pioneer USA. Thus, the members of the board of directors of
Pioneer USA have duties to operate Pioneer USA's business for the benefit of its
sole stockholder, Pioneer Parent, and, as officers of Pioneer Parent, to operate
Pioneer Parent's business in its best interests. Consequently, the duties of the
members of the board of directors of Pioneer USA to the limited partners may
conflict with the duties of those members to Pioneer Parent, Pioneer USA and
their stockholders.



     Neither Pioneer Parent nor Pioneer USA retained an independent
representative to negotiate on behalf of the limited partners of each
partnership because:


     o    neither the partnership agreement for any partnership nor any
          applicable law provides for any procedure to identify and select an
          independent representative, unless each limited partner of the
          partnership agrees to the independent representative;

     o    Pioneer USA, as sole or managing general partner of each partnership,
          still has its fiduciary duty to the limited partners; and

     o    it would be (1) cost-prohibitive to find one or more persons to
          represent the limited partners in all of the partnerships because no
          one other than Pioneer USA owns an interest in all of the partnerships
          and (2) impractical to have 46 independent representatives.

PIONEER USA'S EMPLOYEES PROVIDE SERVICES TO THE PARTNERSHIPS

     None of the partnerships currently has any employees. Each partnership
relies on Pioneer USA's personnel. Pioneer USA provides all management functions
on behalf of each partnership. Therefore, each partnership currently competes
with Pioneer USA for the time and resources of Pioneer USA's employees.

FINANCIAL INTERESTS OF DIRECTORS AND OFFICERS


     The directors and officers of Pioneer Parent and Pioneer USA have equity
interests in Pioneer Parent through stock ownership, stock options and other
stock-based compensation, but do not have financial or equity interests in any
partnership. See "Ownership of Partnership Interests" on page 64. The boards of
directors of Pioneer Parent and Pioneer USA believe that any economic benefit
their directors and officers may obtain from the merger of each partnership, or
the mergers of all of the partnerships in the aggregate, will be minimal, if
any, and will not result in a material economic benefit, if any, to their
directors and officers individually.


THE PARTNERSHIPS PAY OPERATOR FEES TO PIONEER USA

     Pioneer USA operates most of each partnership's wells. Each partnership has
entered into one or more standard industry operating agreements with Pioneer
USA. Those operating agreements establish the base fee paid by the partnership
to Pioneer USA for its lease operating services. That base fee adjusts annually
based on a rate established by the Council of Petroleum Accountants Society, or
COPAS, for the oil and gas industry.


                                      -63-
   74


                       OWNERSHIP OF PARTNERSHIP INTERESTS


     Pioneer Parent does not directly own any partnership interests in any
partnership. Pioneer Parent beneficially owns all of Pioneer USA's partnership
interests in each partnership. Table 6 of Appendix A to this document contains
the voting percentage as of March 31, 2001, of the outstanding limited
partnership interests for each partnership that are beneficially owned by
Pioneer USA as a limited partner. As of March 31, 2001, no person or entity
known by Pioneer USA beneficially owns more than 5% of the outstanding limited
partnership interests in any partnership, except in Parker & Parsley 81-I, Ltd.,
Parker & Parsley 82-I, Ltd. and Parker and Parsley 82-III, Ltd. In those
partnerships, Pioneer USA repurchased and now owns partnership interests
representing the following beneficial ownership percentages:


              Parker & Parsley 81-I, Ltd.                  5.84%
              Parker & Parsley 82-1, Ltd.                 10.73%
              Parker & Parsley 82-III, Ltd.                5.97%

Pioneer USA has sole investment and voting power with respect to partnership
interests it beneficially owns.


     Except as set forth above, none of Pioneer Parent, Pioneer USA, or, to the
knowledge of Pioneer USA, any of their directors or executive officers, or any
associate or majority-owned subsidiary of Pioneer Parent, Pioneer USA or any
such director or officer:


     o    beneficially owns any partnership interests of any partnership; or

     o    has effected any transactions in any partnership interests of any
          partnership during the past 60 days.


         TRANSACTIONS AMONG ANY PARTNERSHIP, PIONEER PARENT, PIONEER USA
                        AND THEIR DIRECTORS AND OFFICERS



     Except as described in this document, there have not been any transactions,
negotiations or material contacts between Pioneer Parent, Pioneer USA, any of
their respective subsidiaries, or, to the knowledge of Pioneer Parent and
Pioneer USA, any director or executive officer of Pioneer Parent or Pioneer USA
or any associate of any such persons, on the one hand, and any partnership or
any of its general partners, including Pioneer USA, directors, officers or
affiliates, on the other hand, that are required to be disclosed pursuant to the
rules and regulations of the SEC. Except as described in this document, none of
Pioneer Parent, Pioneer USA, or, to the knowledge of Pioneer Parent and Pioneer
USA, any director or executive officer of Pioneer Parent or Pioneer USA, has any
agreement, arrangement or understanding with any other person with respect to
any securities of any partnership.



     During March 2001, Pioneer Parent offered to acquire all of the direct oil
and gas interests owned by some former officers and employees of Pioneer Parent
and Pioneer USA in properties in which Pioneer Parent and Pioneer USA own
interests. The merger value for the direct oil and gas interests was equal to
the present value of estimated future net revenues from the oil and gas reserves
attributable to the interests, as of March 31, 2001. In determining the present
value, Pioneer Parent and Pioneer USA used (1) a five-year NYMEX futures price
for oil and gas as of March 2001 with prices held constant after year five at
the year five price, less standard industry adjustments, (2) historical
operating costs adjusted only for those items affected by commodity prices, such
as production taxes and ad valorem taxes, and (3) a 13.5% discount rate. The
consideration offered in the purchases of the direct oil and gas interests was
all cash since offering and registering Pioneer Parent common stock in those
purchases was cost-prohibitive due to the small size of such transactions.



     Additionally, in December 2000, Pioneer Parent received the approval of the
partners of 13 employee limited partnerships to merge with Pioneer USA for total
merger consideration of $2.0 million. Of the total merger consideration, $0.3
million was paid to current Pioneer Parent employees. The merger value of each
employee partnership was equal to the sum of the present value of estimated
future net revenues from the partnership's estimated oil and gas reserves and
its net working capital, in each case as of September 30, 2000, less the cash
distributions on October 15, 2000 and November 15, 2000, by that partnership to
its partners. In determining the present value, Pioneer Parent and Pioneer USA
used (1) a five-year NYMEX futures price for oil and gas as of August 25, 2000
with prices held constant after year five at the year five price, less standard
industry adjustments, (2) historical operating costs adjusted only for those
items affected by commodity prices, such as production taxes and ad valorem
taxes, and (3) a 13.5% discount rate. Using the same parameters as described
above, Pioneer Parent purchased all of the direct oil and gas interests held by
Scott D. Sheffield, its chairman of the board of directors and chief executive
officer, for $0.2 million during October 2000. The consideration paid in the
mergers of the employee limited partnerships and the purchase of Mr. Sheffield's
direct oil and gas interests was all cash. As with the purchases of the direct
oil and gas interests described above, offering and registering Pioneer Parent
common stock in these transactions was cost-prohibitive due to the small size of
such transactions.


     If you approve the merger of each partnership in which you own an interest,
there are various ways that Pioneer USA may use the properties. Pioneer USA may
continue to operate the properties, it may sell the properties to third


                                      -64-
   75


parties, including a royalty trust, or it may spin-off the properties to its
stockholder. Although Pioneer USA plans to operate the properties in the
immediate future following completion of the merger of each partnership, it has
not decided how to use the properties in the long-term.


                                      -65-
   76


                                   MANAGEMENT


PIONEER PARENT



     The following information sets forth the age, business experience during
the past five years, positions and offices with Pioneer Parent, and periods of
service of each director and executive officer of Pioneer Parent.





            NAME            AGE                         POSITION
            ----            ---                         --------
                                  
Scott D. Sheffield           48         Chairman of the Board of Directors, President and Chief
                                        Executive Officer
Timothy L. Dove              44         Executive Vice President and Chief Financial Officer
Dennis E. Fagerstone         52         Executive Vice President
Mark L. Withrow              53         Executive Vice President, General Counsel and Secretary
Danny L. Kellum              46         Executive Vice President -- Domestic Operations
James R. Baroffio            69         Director
R. Hartwell Gardner          66         Director
James L. Houghton            70         Director
Jerry P. Jones               69         Director
Charles E. Ramsey, Jr.       64         Director




     Scott D. Sheffield. Mr. Sheffield, a distinguished graduate of the
University of Texas with a Bachelor of Science degree in Petroleum Engineering,
has been the Chairman of the Board of Directors of Pioneer Parent since August
1999 and the President and Chief Executive Officer of Pioneer Parent since
August 1997. Mr. Sheffield was the Chairman of the Board of Directors, President
and Chief Executive Officer of Parker & Parsley Petroleum Company from October
1990 until August 1997. He was the President and a director of Parker & Parsley
Petroleum Company from May 1990 until October 1990. Mr. Sheffield was the sole
director of Parker & Parsley Petroleum Company from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company, a predecessor of
Parker & Parsley Petroleum Company, as a petroleum engineer in 1979. Mr.
Sheffield served as Vice President-- Engineering of Parker & Parsley Development
Company from September 1981 until April 1985, when he was elected President and
a director. In March 1989, Mr. Sheffield was elected Chairman of the Board of
Directors and Chief Executive Officer of Parker & Parsley Development Company.
Before joining Parker & Parsley Development Company 's predecessor, Mr.
Sheffield was employed as a production and reservoir engineer for Amoco
Production Company.



     Timothy L. Dove. Mr. Dove, a graduate of Massachusetts Institute of
Technology with a Bachelor of Science degree in Mechanical Engineering and the
University of Chicago with an M.B.A., has been Executive Vice President and
Chief Financial Officer of Pioneer Parent since February 2000. He was Executive
Vice President-- Business Development of Pioneer Parent from August 1997 until
February 2000. Mr. Dove joined Parker & Parsley Petroleum Company in May 1994 as
Vice President-- International and was promoted to Senior Vice President--
Business Development in October 1996, in which position he served until August
1997. Before joining Parker & Parsley Petroleum Company, Mr. Dove was employed
with Diamond Shamrock Corp., and its successor, Maxus Energy Corp., in various
capacities in international exploration and production, marketing, refining, and
planning and development.



     Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, has been an Executive Vice President
of Pioneer Parent since August 1997. Mr. Fagerstone served as Executive Vice
President and Chief Operating Officer of MESA Inc. from March 1997 until August
1997. Mr. Fagerstone served as Senior Vice President and Chief Operating Officer
of MESA Inc. from October 1996 to February 1997, and served as Vice President--
Exploration and Production of MESA Inc. from May 1991 to October 1996. Mr.
Fagerstone served as Vice President-- Operations of MESA Inc. from June 1988
until May 1991.



     Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a Bachelor of Science degree in Accounting and Texas Tech University with a
J.D. degree, has been the Executive Vice President, General Counsel and
Secretary of Pioneer Parent since August 1997. He served as Vice President--
General Counsel of Parker & Parsley Petroleum Company from February 1991 until
January 1995, and served as Senior Vice President and General Counsel of Parker
& Parsley Petroleum Company from January 1995 until August 1997. He was Parker &
Parsley Petroleum Company's Secretary from August 1992 until August 1997. Mr.
Withrow joined Parker & Parsley Development Company in January 1991. Before
joining Parker & Parsley Development Company, Mr. Withrow was the managing
partner of the law firm of Turpin, Smith, Dyer, Saxe & MacDonald, Midland,
Texas.



     Danny L. Kellum. Mr. Kellum, a graduate of Texas Tech University with a
Bachelor of Science degree in Petroleum Engineering in 1979, has been Executive
Vice President-- Domestic Operations of Pioneer Parent since May 2000. From
January 2000 until May 2000, Mr. Kellum served as Vice President - Domestic
Operations. From August 1997 until December 1999, Mr. Kellum served as Vice
President-- Permian Division. Mr. Kellum served as Spraberry District Manager
for Parker & Parsley Petroleum Company from 1989 until 1994 and as Vice
President of



                                      -66-
   77


the Spraberry and Permian Divisions for Parker & Parsley Petroleum Company from
1994 until August 1997. He joined Parker & Parsley Petroleum Company in 1981 as
Operations Engineer after a brief career with Mobil Oil Corporation.



     James R. Baroffio. Dr. Baroffio received a B.A. in Geology at the College
of Wooster, Ohio, an M.S. in Geology at Ohio State University, and a Ph.D. in
Geology at the University of Illinois. Before becoming a director of Pioneer
Parent in December 1997, Dr. Baroffio enjoyed a long career with Standard Oil
Company of California, the predecessor of Chevron Corporation, where he served
as President, Chevron Research and Technology Center from 1980 to 1985 and
eventually retired as President of Chevron Canada Resources in 1994. Dr.
Baroffio was a member of the Board of Directors of the Rocky Mountain Oil & Gas
Association and Chairman of the U.S. National Committee of the World Petroleum
Congress. His community leadership positions included membership on the Board of
Directors of Glenbow Museum and the Nature Conservancy of Canada, as well as
serving as President of the Alberta Nature Conservancy.



     R. Hartwell Gardner. Mr. Gardner, a graduate of Colgate University with a
Bachelor of Arts degree in Economics and Harvard University with an M.B.A.,
became a director of Pioneer Parent in August 1997. He served as a director of
Parker & Parsley Petroleum Company from November 1995 until August 1997. Until
his retirement in September 1995, Mr. Gardner was the Treasurer of Mobil Oil
Corporation and Mobil Corporation from 1974 and 1976, respectively. Mr. Gardner
is a member of the Financial Executives Institute of which he served as Chairman
in 1986/1987 and is a Director of Oil Investment Corporation Ltd. and Oil
Casualty Investment Corporation Ltd., Pembroke, Bermuda.



     James L. Houghton. Mr. Houghton is a certified public accountant and a
graduate of Kansas University with a Bachelor of Science degree in Accounting,
as well as a Bachelor of Laws degree. Mr. Houghton has served as a director of
Pioneer Parent since August 1997, and as a director of Parker & Parsley
Petroleum Company from October 1991 until August 1997. Until his retirement in
September 1991, Mr. Houghton was the lead oil and gas tax specialist for the
accounting firm of Ernst & Young LLP, was a member of Ernst & Young's National
Energy Group, and had served as its Southwest Regional Director of Tax. Mr.
Houghton is a member of the American Institute of Certified Public Accountants,
a member of the Oklahoma Society of Certified Public Accountants, a former
Chairman of its Federal and Oklahoma Taxation Committee and past President of
the Oklahoma Institute of Taxation. He has also served as a Director for the
Independent Petroleum Association of America and as a member of its Tax
Committee.



     Jerry P. Jones. Mr. Jones earned a Bachelor of Science degree from West
Texas State College in 1953 and a Bachelor of Law degree from the University of
Texas School of Law in 1959. Mr. Jones has served as a director of Pioneer
Parent since August 1997, and as a director of Parker & Parsley Petroleum
Company from May 1991 until August 1997. Mr. Jones has been an attorney with the
law firm of Thompson & Knight, P.C., Dallas, Texas, since September 1959 and was
a shareholder in that firm until January 1998, when he retired and became of
counsel to the firm. Mr. Jones specialized in civil litigation, especially in
the area of energy disputes.



     Charles E. Ramsey, Jr. Mr. Ramsey is a graduate of the Colorado School of
Mines with a Petroleum Engineering degree and a graduate of the Smaller Company
Management program at the Harvard Graduate School of Business Administration.
Mr. Ramsey has served as a director of Pioneer Parent since August 1997. Mr.
Ramsey served as a director of Parker & Parsley Petroleum Company from October
1991 until August 1997. Since October 1991, he has operated Ramsey Energy LLC,
an independent management and financial consulting firm. From June 1958 until
June 1986, Mr. Ramsey held various engineering and management positions in the
oil and gas industry and, for six years before October 1991, was a Senior Vice
President in the Corporate Finance Department of Dean Witter Reynolds Inc. in
Dallas, Texas. His industry experience includes 12 years of senior management
experience in the positions of President, Chief Executive Officer and Executive
Officer and Executive Vice President of May Petroleum Inc. Mr. Ramsey is also a
former director of MBank Dallas, the Dallas Petroleum Club and Lear Petroleum
Corporation.





PIONEER USA

     The following information sets forth the age, business experience during
the past five years, positions and offices with Pioneer USA, and periods of
service of each director and executive officer of Pioneer USA.



         NAME                AGE                   POSITION
         ----                ---                   --------
                                  
Scott D. Sheffield           48         President
Timothy L. Dove              44         Director, Executive Vice President and
                                        Chief Financial Officer
Dennis E. Fagerstone         52         Director and Executive Vice President
Mark L. Withrow              53         Director, Executive Vice President,
                                        General Counsel and Secretary
Danny L. Kellum              46         Director and Executive Vice President



                                      -67-
   78



     Scott D. Sheffield. Mr. Sheffield has been the President of Pioneer USA
since August 1997 and served as the Chairman of the Board of Directors of
Pioneer USA from August 1997 until June 1999. He served as a Director of Pioneer
USA's predecessor, Parker & Parsley Petroleum USA, Inc., from January 1991 until
August 1997. He was an Executive Vice President of Parker & Parsley Petroleum
USA, Inc. from December 1995 until August 1997. He was the President of Parker &
Parsley Petroleum USA, Inc. from December 1993 until December 1995. Mr.
Sheffield was President and Chief Executive Officer of Parker & Parsley
Petroleum USA, Inc. from January 1991 until December 1993. Mr. Sheffield's other
business experience and biographical information are set forth above under
"Management-- Pioneer Parent."



     Timothy L. Dove. Mr. Dove has been a Director of Pioneer USA since August
1997 and has been Executive Vice President and Chief Financial Officer of
Pioneer USA since February 2000. He was the Executive Vice President-- Business
Development of Pioneer USA from August 1997 until February 2000. He served as a
Director of Parker & Parsley Petroleum USA, Inc. from June 1997 until August
1997. He was a Senior Vice President of Parker & Parsley Petroleum USA, Inc.
from October 1996 until August 1997. He was a Vice President of Parker & Parsley
Petroleum USA, Inc. from December 1995 until October 1996. Mr. Dove's other
business experience and biographical information are set forth above under
"Management-- Pioneer Parent."



     Dennis E. Fagerstone. Mr. Fagerstone has been a Director of Pioneer USA
since August 1997 and an Executive Vice President of Pioneer USA since August
1997. Mr. Fagerstone's other business experience and biographical information
are set forth above under "Management-- Pioneer Parent."



     Mark L. Withrow. Mr. Withrow has been a Director of Pioneer USA since
August 1997. He became an Executive Vice President, the General Counsel and the
Secretary of Pioneer USA in August 1997. He served as a Director of Parker &
Parsley Petroleum USA, Inc. from January 1996 until August 1997. He was a Senior
Vice President and the Secretary of Parker & Parsley Petroleum USA, Inc. from
January 1995 until August 1997. He was a Vice President and the Secretary of
Parker & Parsley Petroleum USA, Inc. from December 1993 until January 1995. He
was a Vice President of Parker & Parsley Petroleum USA, Inc. from January 1991
until December 1993. Mr. Withrow's other business experience and biographical
information are set forth above under "Management-- Pioneer Parent."



     Danny L. Kellum. Mr. Kellum has been a Director of Pioneer USA since
February 2000, and has been Executive Vice President of Pioneer USA since May
2000. He served as Vice President -- Domestic Operations of Pioneer USA from
January 2000 until May 2000, as Vice President -- Permian Division of Pioneer
USA from April 1998 until December 1999 and as Vice President -- Spraberry
Division of Pioneer USA from December 1997 until March 1998. Mr. Kellum's other
business experience and biographical information are set forth above under
"Management -- Pioneer Parent."



                                      -68-
   79


                                 PIONEER PARENT


     Pioneer Parent is a large independent exploration and production company
with total proved reserves equivalent to 3.8 trillion cubic feet of natural gas,
or 628 million barrels of oil. Pioneer Parent's proved reserves are balanced
equally between natural gas and oil, and Pioneer Parent has a
reserves-to-production ratio of 14 years. Three core areas in the United States
comprise 67% of Pioneer Parent's reserve base: the Hugoton gas field, the West
Panhandle gas field, and the Spraberry oil and natural gas field. Pioneer Parent
also has domestic properties in East Texas, the Gulf Coast, and the offshore
Gulf of Mexico as well as a significant international presence through its
properties in Argentina, Canada, South Africa, and Gabon.



     Pioneer Parent seeks to increase net asset value and production by
combining lower risk development drilling with higher risk exploration activity.
Pioneer Parent has identified over 1,700 development drilling locations on its
properties in the U.S., Argentina and Canada. Approximately 76% of the
identified 1,700 development drilling locations have proved undeveloped reserves
attributable to them. Pioneer Parent's exploration program is focused in the
deepwater Gulf of Mexico, the Gulf Coast shelf, South Africa and Gabon. Pioneer
Parent expects significant new production from the deepwater Gulf of Mexico and
South Africa in 2002 and 2003 as it builds on its recent exploration successes
in those areas. The production from Pioneer Parent's long-lived reserves in the
Spraberry, Hugoton and West Panhandle fields are expected to provide stable cash
flows to fund Pioneer Parent's development and exploration activities.



     During 2000, Pioneer Parent spent $340 million for capital expenditures to
add 437 billion cubic feet of natural gas equivalent reserves. As a consequence,
in 2000 Pioneer Parent replaced 167% of its production at an acquisition and
finding cost of $.78 per Mcf equivalent. Pioneer Parent's acquisition and
finding cost is the result obtained by dividing total costs incurred by the sum
of revisions of previous estimates, purchases of minerals-in-place and new
discoveries and extensions. Pioneer Parent drilled 296 wells with 90% success
worldwide, including 83 exploration and extension wells with 73% success.



     For 2001, Pioneer Parent has budgeted $430 million of capital expenditures,
a 26% increase over 2000 capital expenditures but less than expected available
cash flow. Approximately 73% of the 2001 capital expenditure budget is for
development activities with the remaining 27% for exploration. Pioneer Parent
plans to drill approximately 460 development wells and 26 exploratory wells in
its 2001 program, and approximately 65% of the capital expenditures will be for
drilling activities in the U.S.


KEY PROJECTS TO INCREASE PRODUCTION


     Pioneer Parent expects to increase its production of oil and gas from
current levels by 25% to 30% on a gas equivalent basis by early to mid 2003,
primarily from four projects. The production increases anticipated from the four
projects are derived from currently booked proved undeveloped reserves. The
projects in general build on Pioneer Parent's recent exploration successes.



     o    The Canyon Express project is a joint development of three deepwater
          Gulf of Mexico discoveries, including Pioneer Parent's Aconcagua and
          Camden Hills fields. The project is being developed with a capacity to
          deliver 500 million cubic feet of natural gas per day by the summer of
          2002. Pioneer Parent owns an 18% interest in the Canyon Express
          project and expects that production from the project will increase
          Pioneer Parent's North American natural gas production by 30% from
          current levels.



     o    Pioneer Parent's first well in offshore South Africa confirmed the
          presence of commercial oil reserves and resulted in Pioneer Parent's
          plans to develop the Sable oil field. First production from the field
          is expected in late 2002 or early 2003 at daily rates of 25 to 30
          thousand barrels per day. Pioneer Parent has a 35% working interest in
          the field, and production from the project is expected to increase
          Pioneer Parent's total oil production by more than 20%. Pioneer Parent
          has also discovered oil and natural gas at its Boomslang prospect in
          offshore South Africa and plans a second well on the prospect later in
          2001.



     o    The Devils Tower discovery was Pioneer Parent's second in the
          deepwater Gulf of Mexico. The oil field has been successfully
          appraised, and development plans call for first production in early
          2003 with additional drilling planned this year. Pioneer Parent has a
          25% working interest in the field, and production from the field is
          expected to increase Pioneer Parent's total oil production by
          approximately 20% from current levels.



     o    In the East Texas Bossier natural gas play, Pioneer Parent holds
          interests in over 130,000 acres and plans to drill or participate in
          over 35 wells during 2001. The play's strong initial natural gas flow
          rates are expected to provide significant new production growth.



                                      -69-
   80


MORE INFORMATION


     A more complete description of Pioneer Parent and its business is found in
the reports that Pioneer Parent files with the SEC. Please see "Where You Can
Find More Information" on the inside front cover page of this document. Pioneer
Parent's business, and its expectations about its future, are subject to many
risks. Please also read "Risks Associated with an Investment in Pioneer Parent"
under the caption "Risk Factors" beginning on page 17 of this document.




                                      -70-
   81


                                THE PARTNERSHIPS

GENERAL


     Pioneer USA's predecessor, Parker & Parsley Petroleum USA, Inc. or its
predecessors or affiliates, sponsored each partnership. As a result of the
merger of Parker & Parsley Petroleum Company and MESA Inc. to form Pioneer
Parent on August 7, 1997, Pioneer USA became the managing or sole general
partner of each partnership.



     Appendix A to this document sets forth information about each partnership,
including proved reserves as of December 31, 2000, estimated reserves as of
March 31, 2001, oil and gas production, average sales prices and production
costs, productive wells and developed acreage, and historical cash
distributions. In addition, the supplement for each partnership constitutes an
integral part of this document. You should read Appendix A and the supplement
carefully in their entirety.


THE DRILLING PARTNERSHIPS

     The drilling partnerships consist of the following 43 limited partnerships
that were formed from 1981 through 1991:



          NAME                                          STATE OF FORMATION
          ----                                          ------------------
                                                     
Parker & Parsley 81-I, Ltd.                                   Texas
Parker & Parsley 81-II, Ltd.                                  Texas
Parker & Parsley 82-I, Ltd.                                   Texas
Parker & Parsley 82-II, Ltd.                                  Texas
Parker & Parsley 82-III, Ltd.                                 Texas
Parker & Parsley 83-A, Ltd.                                   Texas
Parker & Parsley 83-B, Ltd.                                   Texas
Parker & Parsley 84-A, Ltd.                                   Texas
Parker & Parsley 85-A, Ltd.                                   Texas
Parker & Parsley 85-B, Ltd.                                   Texas
Parker & Parsley Private Investment 85-A, Ltd.                Texas
Parker & Parsley Selected 85 Private Investment, Ltd.         Texas
Parker & Parsley 86-A, Ltd.                                   Texas
Parker & Parsley 86-B, Ltd.                                   Texas
Parker & Parsley 86-C, Ltd.                                   Texas
Parker & Parsley Private Investment 86, Ltd.                  Texas
Parker & Parsley 87-A Conv., Ltd.                             Texas
Parker & Parsley 87-A, Ltd.                                   Texas
Parker & Parsley 87-B Conv., Ltd.                             Texas
Parker & Parsley 87-B, Ltd.                                   Texas
Parker & Parsley Private Investment 87, Ltd.                  Texas
Parker & Parsley 88-A Conv., L.P.                           Delaware
Parker & Parsley 88-A, L.P.                                 Delaware
Parker & Parsley 88-B Conv., L.P.                           Delaware
Parker & Parsley 88-B L.P.                                  Delaware
Parker & Parsley 88-C Conv., L.P.                           Delaware
Parker & Parsley 88-C, L.P.                                 Delaware
Parker & Parsley Private Investment 88, L.P.                Delaware
Parker & Parsley 89-A Conv., L.P.                           Delaware
Parker & Parsley 89-A, L.P.                                 Delaware
Parker & Parsley 89-B Conv., L.P.                           Delaware
Parker & Parsley 89-B, L.P.                                 Delaware
Parker & Parsley Private Investment 89, L.P.                Delaware
Parker & Parsley 90-A Conv., L.P.                           Delaware
Parker & Parsley 90-A, L.P.                                 Delaware
Parker & Parsley 90-B Conv., L.P.                           Delaware
Parker & Parsley 90-B, L.P.                                 Delaware
Parker & Parsley 90-C Conv., L.P.                           Delaware
Parker & Parsley 90-C, L.P.                                 Delaware
Parker & Parsley Private Investment 90, L.P.                Delaware



                                      -71-
   82



          NAME                                          STATE OF FORMATION
          ----                                          ------------------
                                                     
Parker & Parsley 90 Spraberry Private Development, L.P.     Delaware
Parker & Parsley 91-A, L.P.                                 Delaware
Parker & Parsley 91-B, L.P.                                 Delaware


     Each drilling partnership was formed to establish long-lived oil and gas
reserves primarily by drilling low-risk development wells in the Spraberry field
of the Permian Basin of West Texas. The oil and gas properties of each drilling
partnership consist primarily of leasehold interests in producing properties
located in Texas. The partners of a drilling partnership received a tax benefit
from drilling activities in the partnership's first year. Subsequently, each
drilling partnership has regularly distributed its net cash flow. As of the date
of this document, each drilling partnership has expended all of its initial
capital contributions.

     For a discussion of transactions between each drilling partnership and
Pioneer USA, see the notes to the financial statements of each drilling
partnership included in the supplement for the partnership.

THE INCOME PARTNERSHIPS

     The income partnerships consist of the following three limited partnerships
that were formed in 1987 and 1988:



          NAME                                          STATE OF FORMATION
          ----                                          ------------------
                                                     
Parker & Parsley Producing Properties 87-A, Ltd.              Texas
Parker & Parsley Producing Properties 87-B, Ltd.              Texas
Parker & Parsley Producing Properties 88-A, L.P.           Delaware


     The primary objective of each income partnership was to acquire long-lived,
producing oil and gas properties in the Spraberry Field of the Permian Basin of
West Texas. Subsequently, each income partnership has regularly distributed its
net cash flow. As of the date of this document, each income partnership has
expended all of its initial capital contributions.

     For a discussion of transactions between each income partnership and
Pioneer USA, see the notes to the financial statements of each income
partnership included in the supplement for the partnership.



                                      -72-
   83

                COMPARISON OF RIGHTS OF STOCKHOLDERS AND PARTNERS

GENERAL


     The rights of Pioneer Parent stockholders are currently governed by the
Delaware General Corporation Law and the certificate of incorporation and bylaws
of Pioneer Parent. The rights of the limited partners of each partnership are
currently governed by the Delaware Revised Uniform Limited Partnership Act or
the Texas Revised Limited Partnership Act and, in either case, the partnership
agreement of the partnership. Accordingly, on completion of the merger of each
partnership, the rights of Pioneer Parent stockholders and of limited partners
who become Pioneer Parent stockholders in the merger of their partnerships will
be governed by the Delaware General Corporation Law, Pioneer Parent's
certificate of incorporation and Pioneer Parent's bylaws. The following is a
summary of the material differences between the current rights of Pioneer Parent
stockholders and those of the limited partners of each partnership.



     The following summary of the material differences between the Pioneer
Parent certificate of incorporation, the Pioneer Parent bylaws and the
partnership agreement for each partnership may not contain all the information
that is important to you. To review all provisions and differences of such
documents in full detail, please read the full text of these documents, the
Delaware General Corporation Law, the Delaware Revised Uniform Limited
Partnership Act and the Texas Revised Limited Partnership Act. Copies of the
Pioneer Parent certificate of incorporation, the Pioneer Parent bylaws and the
partnership agreement for each partnership in which you own an interest will be
sent to you upon request. For information on how these documents may be
obtained, see "Where You Can Find More Information" on the inside front cover
page of this document.



     Pioneer Parent's certificate of incorporation and bylaws will not be
amended in conjunction with the merger of any partnership.


SUMMARY COMPARISON OF TERMS OF SHARES OF PIONEER PARENT COMMON STOCK AND
PARTNERSHIP INTERESTS




----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
                                             LIQUIDITY AND MARKETABILITY
----------------------------------------------------------------------------------------------------------------------
Shares of Pioneer Parent common stock are generally freely   The partnership interests of each partnership may not
transferable.  The shares of Pioneer Parent common stock     be transferred if, in the opinion of counsel to the
that are currently outstanding are traded on the New York    partnership, (1) such transfers would result in the
Stock Exchange and the Toronto Stock Exchange, and the       termination of the partnership for federal income tax
shares of Pioneer Parent common stock to be issued in the    purposes under Section 708 of the Internal Revenue
merger of each participating partnership have been           Code, or (2) such transfers may not be effected without
approved for listing on the New York Stock Exchange and      registration under the Securities Act of 1933 or would
the Toronto Stock Exchange upon official notice of           result in the violation of any applicable state
issuance.                                                    securities laws.  Clause (1) is not applicable to
                                                             Parker & Parsley 85-A, Ltd., Parker & Parsley 85-B,
                                                             Ltd., Parker & Parsley Private Investment 85-A, Ltd.,
                                                             Parker & Parsley Selected 85 Private Investment, Ltd.,
                                                             Parker & Parsley Private Investment 86, Ltd., Parker &
                                                             Parsley 87-A Conv., Ltd., Parker & Parsley 87-A, Ltd.,
                                                             Parker & Parsley 87-B Conv., Ltd. and Parker & Parsley
                                                             87-B, Ltd. and Parker & Parsley Private Investment 87,
                                                             Ltd. In addition, no transferee of a partnership
                                                             interest has the right to become a substitute limited
                                                             partner unless, among other things, such substitution
                                                             is approved by Pioneer USA, who may grant or withhold
                                                             such consent in its absolute discretion.  In view of
                                                             the foregoing restrictions, it was never intended that
                                                             the partnership interests would be actively traded. No
                                                             broad-based secondary market for the partnership
                                                             interests of any partnership exists.
----------------------------------------------------------------------------------------------------------------------




                                      -73-
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----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
                                                RIGHTS OF REPURCHASE
----------------------------------------------------------------------------------------------------------------------
Pioneer Parent's stockholders have no right to present       Within the time periods specified in the partnership
their shares of Pioneer Parent common stock for repurchase   agreements of Parker & Parsley 82-I, Ltd., Parker &
by Pioneer Parent or any other person.                       Parsley 82-II, Ltd., Parker & Parsley 82-III, Ltd.,
                                                             Parker & Parsley 83-A, Ltd., Parker & Parsley 83-B,
                                                             Ltd. and Parker & Parsley 84-A, Ltd., a limited partner
                                                             of any of those partnerships may tender all or, subject
                                                             to some limitations, part of his partnership interests
                                                             in the partnership to Pioneer USA for repurchase in
                                                             accordance with the partnership agreement for the
                                                             partnership.  See "Risk Factors -- Risk Factors Relating
                                                             to the Merger of Each Partnership -- Repurchase Rights
                                                             Terminate on Completion of the Mergers."  A comparison
                                                             of the merger value for each of these partnerships and
                                                             the repurchase prices in 2001 is set forth in Table 8
                                                             of Appendix A.

----------------------------------------------------------------------------------------------------------------------
                                MANAGEMENT, MANAGEMENT LIABILITY AND INDEMNIFICATION
----------------------------------------------------------------------------------------------------------------------

Pioneer Parent is managed by a board of directors elected    Each of the partnerships is managed by Pioneer USA,
by its stockholders.  Under Delaware law, the directors      which generally has exclusive authority over each of
are accountable to Pioneer Parent and its stockholders as    the partnership's operations.  The limited partners may
fiduciaries and are required to perform their duties (1)     not participate in management of the partnerships.
in good faith, (2) in a manner believed to be in the best    Under Delaware and Texas law, Pioneer USA and any
interests of Pioneer Parent and its stockholders and (3)     nonmanaging general partners of any of the partnerships
with such care, including reasonable inquiry, as an          are accountable to the partnership as fiduciaries and
ordinarily prudent person in a like position would use       consequently are required to exercise good faith and
under similar circumstances.  The liability of the           integrity in all of their dealings with respect to the
directors is limited pursuant to the provisions of           affairs of the partnership.  Under Texas or Delaware
Delaware law and Pioneer Parent's certificate of             law, as applicable, Pioneer USA and any nonmanaging
incorporation, which limits a director's liability for       general partners of any of the partnerships have
monetary damages to Pioneer Parent or its stockholders for   liability for the payment of partnership obligations
breach of the director's duty of care, where a director      and debts, unless limitations upon such liability are
fails to exercise sufficient care in carrying out the        expressly stated in the obligation.  The partnership
responsibilities of office.  Such provisions, however,       agreement of each partnership provides generally that
would not protect a director for (1) a breach of duty of     Pioneer USA, any nonmanaging general partners of the
loyalty, (2) intentional misconduct or knowing violations    partnership and, in some cases, their affiliates will
of law, (3) unlawful dividend payments or redemption of      be indemnified for losses relating to acts performed or
stock, or (4) any transaction in which the director          omitted to be performed in good faith and in the best
derived an improper personal benefit. Such provisions do     interests of the partnership; provided that the conduct
not foreclose any other remedy which might be available to   of Pioneer USA, any such nonmanaging general partner or
Pioneer Parent or its stockholders.  Pioneer Parent's        affiliate, as applicable, did not constitute negligence
certificate of incorporation and Delaware law provide        or misconduct.  Pioneer USA and any nonmanaging general
broad indemnification rights to directors and officers who   partners of the partnership may be removed by an
                                                             affirmative vote of limited partners holding a majority
     o   act in good faith,                                  of the outstanding  limited partnership interests in
                                                             the partnership; provided, that an opinion of counsel
     o   in a manner reasonably believed to be in or not     to the limited partners and acceptable to the
         opposed to the best interests of Pioneer Parent     partnership is delivered to the partnership to the
         and,                                                effect that the exercise of such rights by the limited
                                                             partners (1) will not result in the loss of the limited
     o   with respect to criminal actions or proceedings,    partners' limited liability and (2) will not adversely
         without reasonable cause to believe their conduct   affect the tax status of the partnership, Pioneer USA
         was unlawful.                                       or the other partners.

----------------------------------------------------------------------------------------------------------------------




                                      -74-
   85




----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
Pioneer Parent's certificate of incorporation also
requires Pioneer Parent to indemnify its officers and
directors under some circumstances for expenses or
liabilities incurred as a result of litigation. In
addition, Pioneer Parent's certificate of incorporation
authorizes Pioneer Parent to advance expenses incurred in
the defense of its directors and officers.  Pioneer Parent
intends to take full advantage of those provisions and has
entered into agreements with Pioneer Parent's directors
and officers indemnifying them to the fullest extent
permitted by Delaware law.

----------------------------------------------------------------------------------------------------------------------
                                               MANAGEMENT COMPENSATION
----------------------------------------------------------------------------------------------------------------------
The board of directors of Pioneer Parent appoints officers   Each partnership reimburses Pioneer USA for its general
to serve at the discretion of the board of directors.  The   and administrative expenses.
board of directors of Pioneer Parent determines the
officer salaries and incentive compensation; provided,
that the board of directors of Pioneer Parent may delegate
the power to determine such compensation to the chairman
of the board, the president or any committee of the board
of directors.
----------------------------------------------------------------------------------------------------------------------
                                                 MANAGEMENT CONTROL
----------------------------------------------------------------------------------------------------------------------
Pioneer Parent's board of directors has exclusive control    Under the partnership agreement of each partnership,
over Pioneer Parent's business and affairs subject only to   Pioneer USA is generally vested with all management
the restrictions in Pioneer Parent's certificate of          authority to manage, control, administer and operate
incorporation and bylaws.  Pioneer Parent's stockholders     the business, properties and affairs of the
have the right to elect members of the board of directors    partnership, including authority and responsibility for
by a plurality vote at each annual meeting of the            overseeing all executive, supervisory and
stockholders.  The directors are accountable to Pioneer      administrative services rendered to the partnership.
Parent and its subsidiaries as fiduciaries.                  Pioneer USA and any nonmanaging general partners have
                                                             the right to continue to serve in such capacity unless
                                                             Pioneer USA or such nonmanaging general partner is
                                                             removed upon the affirmative vote of limited partners
                                                             holding a majority of the outstanding limited
                                                             partnership interests in the partnership; provided,
                                                             that an opinion of counsel to the limited partners, and
                                                             acceptable to the partnership, is delivered to the
                                                             partnership to the effect that the exercise of such
                                                             rights by the limited partners (1) will not result in
                                                             the loss of the limited partners' limited liability and
                                                             (2) will not adversely affect the tax status of the
                                                             partnership, Pioneer USA or the other partners.  The
                                                             limited partners of each partnership have no right to
                                                             participate in the management and control of the
                                                             partnership and have no voice in the partnership's
                                                             affairs except for some limited matters that may be
                                                             submitted to a vote of the limited partners under the
                                                             terms of the partnership agreement of the partnership.
                                                             See "Voting Rights and Amendments" below.  Pioneer USA
                                                             is accountable as a fiduciary to each partnership.
----------------------------------------------------------------------------------------------------------------------




                                      -75-
   86





----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
                                            VOTING RIGHTS AND AMENDMENTS
----------------------------------------------------------------------------------------------------------------------
Pioneer Parent's certificate of incorporation provides       Generally, meetings of each partnership may be called
that (1) stockholders of Pioneer Parent may act only at      by Pioneer USA or by limited partners owning at least
annual or special meetings of stockholders and not by        10% of the outstanding limited partnership interests.
written consent, (2) Pioneer Parent will hold an annual      The limited partners may conduct any partnership
meeting each calendar year at which its stockholders will    business at such meeting which is permitted under the
elect directors, (3) special meetings of stockholders may    partnership agreement for such partnership and is
be called only by the board of directors, and (4) only       specified in the notice of such meeting, but the
business proposed by the board of directors may be           limited partners may not engage in any activity which
considered at special meetings of stockholders.              would be deemed taking part in the management or
                                                             control of the partnership's business.
----------------------------------------------------------------------------------------------------------------------
Most amendments to Pioneer Parent's certificate of           Amendments to the partnership agreement of each
incorporation require the approval of the stockholders who   partnership generally require the approval by limited
own a majority of the outstanding shares of Pioneer Parent   partners holding a majority of outstanding limited
common stock.  A number of fundamental amendments,           partnership interests in the partnership.  An amendment
however, require approval by a greater percentage of         that has any of the following effects requires the
stockholders.  For example, any amendment to the following   unanimous approval of Pioneer USA and the limited
provisions requires the approval of two-thirds of the        partners: (1) increases the liability or duties of any
stockholders: (1) election of directors, (2) authority of    of the partners, (2) changes the contributions required
the board of directors, (3) stockholder meetings and (4)     of the partners, (3) provides for any reallocation of
limitation on the liability of directors.  Any amendment     profits, losses or deductions to the detriment of a
to the provision that prohibits action by the written        partner, (4) establishes any new priority in one or
consent of the stockholders in lieu of a meeting requires    more partners as to the return of capital contributions
the approval of 80% of the stockholders.  In addition, the   or as to profits, losses, deductions or distribution to
following actions require the approval of 80% of the         the detriment of a partner, or (5) causes the
stockholders and the approval of two-thirds of the           partnership to be taxed as a corporation.  Pioneer USA
disinterested stockholders:  (1) any merger, consolidation   may, in its sole discretion, adopt any of the following
or share exchange involving any person, other than Pioneer   amendments: (1) change the name of the partnership, (2)
Parent or a subsidiary of Pioneer Parent, who beneficially   change the location of the principal place of business
owns 10% or more of the outstanding voting securities of     of the partnership, (3) admit a new or substitute
Pioneer Parent, which person we call a related party, (2)    limited partner, (4) modify its general partnership
some sales, leases, exchanges or similar transactions with   interest as a result of a transfer of a portion of such
related parties, (3) some issuances of securities to         interest, (5) correct a typographical error, or (6) any
related parties, (4) adoption of any plan or proposal for    other similar change where the Pioneer USA determines
liquidation of Pioneer Parent initiated by related           that the amendment will not adversely affect the
parties, or (5) any series or combination of any of the      limited partners and Pioneer USA believes the amendment
actions described in clauses (1) through (4).                is necessary or advisable to qualify the partnership
                                                             under the laws of a state in which it engages or
                                                             proposes to engage in business or to keep the
                                                             partnership from being treated as a corporation for tax
                                                             purposes.
----------------------------------------------------------------------------------------------------------------------





                                      -76-
   87




----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
                                              ANTI-TAKEOVER PROVISIONS
----------------------------------------------------------------------------------------------------------------------
The certificate of incorporation and bylaws of Pioneer       There are no anti-takeover provisions in the
Parent and the Delaware General Corporation Law include a    partnership agreement for any of the partnerships or
number of provisions which may have the effect of            under Delaware or Texas, as the case may be,
encouraging persons considering unsolicited tender offers    partnership law.
or other unilateral takeover proposals to negotiate with
Pioneer Parent's board of directors rather than pursue
non-negotiated takeover attempts.  These provisions
include (1) a classified board of directors, (2) advance
notice requirements for shareholder proposals and director
nominations, (3) restrictions on certain business
combinations and (4) prohibition against actions approved
by written consent without the approval of a specified
percentage of the shareholders.
----------------------------------------------------------------------------------------------------------------------
                                               CONTINUITY OF EXISTENCE
----------------------------------------------------------------------------------------------------------------------
Pioneer Parent has a perpetual existence.                    Except for the following partnerships, each partnership
                                                             has a finite life of 50 years from the year of its
                                                             formation.  The following partnerships continue until
                                                             terminated by mutual agreement of the partners of the
                                                             partnership:

                                                                  Parker & Parsley 81-I, Ltd.
                                                                  Parker & Parsley 81-II, Ltd.
                                                                  Parker & Parsley 82-I, Ltd.
                                                                  Parker & Parsley 82-II, Ltd.
                                                                  Parker & Parsley 82-III, Ltd.
                                                                  Parker & Parsley 83-A, Ltd.
                                                                  Parker & Parsley 83-B, Ltd.
                                                                  Parker & Parsley 84-A, Ltd.
----------------------------------------------------------------------------------------------------------------------
                                                  LIMITED LIABILITY
----------------------------------------------------------------------------------------------------------------------
A stockholder's liability will generally be limited to       Assuming the limited partners of a partnership do not
such stockholder's contribution to Pioneer Parent's          take part in the management or control of the business
capital. Under Delaware law, Pioneer Parent's stockholders   of such partnership, a limited partner's liability is
will not be liable for Pioneer Parent's debts or             generally limited to the limited partner's contribution
obligations.  The shares of Pioneer Parent common stock      to the capital of the partnership and such limited
offered by Pioneer Parent under this document, upon          partner's share of assets and undistributed profits of
issuance, will be fully paid and nonassessable.              the partnership.  A limited partner will receive a
                                                             return of the limited partner's capital contribution to
                                                             the partnership to the extent that a distribution to
                                                             the limited partner reduces the limited partner's share
                                                             of the fair value of the partnership's net assets below
                                                             the value of the limited partner's unreturned capital
                                                             contributions.  A substituted limited partner is
                                                             subject to the liabilities and obligations of the
                                                             substituted limited partner's assignor, except those
                                                             liabilities of which the substituted limited partner
                                                             was unaware at the time he became a substituted limited
                                                             partner and which could not be ascertained from the
                                                             partnership agreement of the partnership.
----------------------------------------------------------------------------------------------------------------------




                                      -77-
   88





----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
                                          BUSINESS ACTIVITIES AND FINANCING
----------------------------------------------------------------------------------------------------------------------
Pioneer Parent's mission is to provide its stockholders      The business operations of each partnership have
with superior investment returns through strategies that     consisted of the development and production of oil and
maximize Pioneer Parent's long-term profitability and net    gas reserves.  Each partnership has expended its
asset values.  The strategies employed to achieve this       initial partnership capital, and additional properties
mission are anchored by Pioneer Parent's long-lived          cannot be acquired.  Operations can be financed only
Spraberry oil and gas field and Hugoton and West Panhandle   through permitted borrowings, reinvestment of earnings
gas fields' reserves and production.  Underlying these       not distributed, permitted assessments, or permitted
fields are approximately 67% of Pioneer Parent's proved      sales of assets.  Each partnership generally is
oil and gas reserves which have a remaining productive       required to distribute to its partners all or
life in excess of 40 years.  The stable base of oil and      substantially all its net cash flow from operations,
gas production from these fields generates operating cash    after provision for any reserves deemed appropriate by
flows that allow Pioneer Parent the financial flexibility    Pioneer USA.
to selectively reinvest capital:


o    to develop and increase production from existing
     properties through low-risk development drilling
     activities;
o    to leverage cost containment opportunities to achieve
     operating and technical efficiencies; and
o    to pursue strategic acquisitions in Pioneer Parent's
     core areas that will complement Pioneer Parent's
     existing asset base and provide additional growth
     opportunities.

Pioneer Parent also has the financial flexibility to use
portions of its operating cash flows:

o    to selectively expand into new geographic areas that
     feature producing properties and provide exploration
     or exploitation opportunities;
o    to invest in the personnel and technology necessary
     to increase Pioneer Parent's exploration
     opportunities; and
o    to enhance liquidity.

This flexibility allows Pioneer Parent to take advantage
of future exploration, development and acquisition
opportunities.
Pioneer Parent may engage in any phase of the oil and gas
business and any other lawful business.  Pioneer Parent
may finance its operations and the acquisition of
additional properties through, among other things, the
issuance of additional shares of Pioneer Parent common
stock, borrowings, and the reinvestment of earnings not
distributed to stockholders.
----------------------------------------------------------------------------------------------------------------------
                                                 FINANCIAL REPORTING
----------------------------------------------------------------------------------------------------------------------
Pioneer Parent is subject to the reporting requirements of   For a list of the partnerships that are subject to the
the Securities Exchange Act of 1934.                         reporting requirements of the Securities Exchange Act
                                                             of 1934, see "Where You Can Find More Information" on
                                                             the inside front cover page of this document. In
                                                             addition, the partnership agreement of each partnership
                                                             requires that some reports be delivered to the limited
                                                             partners.
----------------------------------------------------------------------------------------------------------------------



                                      -78-
   89





----------------------------------------------------------------------------------------------------------------------
                          SHARES                                              PARTNERSHIP INTERESTS
----------------------------------------------------------------------------------------------------------------------
                                                          
                                                   TAX INFORMATION
----------------------------------------------------------------------------------------------------------------------
"Double taxation" at the corporate and stockholder levels    None of the partnerships is a taxable entity for
typically results when a corporation such as Pioneer         federal income tax purposes.  The partners of each
Parent earns income and distributes that income to its       partnership are required to take into account their pro
stockholders in the form of dividends.  Stockholders will    rata share of the partnership's income, gains, losses,
only recognize income on amounts actually distributed by     and deductions, regardless of whether they receive any
Pioneer Parent.  Distributions made by Pioneer Parent out    cash distributions from the partnership.  Some partners
of current or accumulated earnings and profits are taxed     may be entitled to percentage depletion.  A partner
as dividend income.  Distributions in excess of current or   will be required to recapture some deductions and
accumulated earnings and profits are treated as a            credits upon the sale of all or a portion of his
non-taxable return of basis to the extent of stockholders'   partnership interests.
adjusted basis in their shares, with the excess taxed as
capital gain.
Dividends, if any, received by stockholders from Pioneer     A partner's share of a partnership's income and loss
Parent generally will constitute portfolio income, and       will be subject to the "passive activity" limitations.
cannot be offset with losses from "passive activities."      Under the passive activity rules, losses of a partner
Losses and credits generated within Pioneer Parent do not    arising from his ownership of partnership interests may
pass through to the stockholders.  After the end of          be used to offset passive income from another passive
Pioneer Parent's taxable year, stockholders will receive     investment and income of a partner arising from his
Form 1099-DIV to report their dividend income.               ownership of partnership interests may only be offset
                                                             with passive losses from another passive investment.
                                                             For a discussion of the tax consequences associated
                                                             with the merger of each partnership, see "The Merger of
                                                             Each Partnership-- Material U.S. Federal Income Tax
                                                             Consequences."
----------------------------------------------------------------------------------------------------------------------
                       DIVIDEND OR DISTRIBUTION POLICY AND PARTICIPATION IN PROFITS AND LOSSES
----------------------------------------------------------------------------------------------------------------------
The shares of Pioneer Parent common stock constitute         For a description of the distribution policies of each
equity interests in Pioneer Parent.  Each stockholder will   partnership, see "Risk Factors-- Risks Associated with
be entitled to his pro rata share of the dividends made      an Investment in Pioneer Parent-- Pioneer Parent Might
with respect to the Pioneer Parent common stock.  The        Not Declare Dividends." The average quarterly cash
dividends payable to the stockholders are not fixed in       distributions by each partnership for 1999, 2000 and
amount and are only paid if, as and when declared by         the year-to-date in 2001 are set forth in Table 7 of
Pioneer Parent's board of directors.  Dividends payable      Appendix A. For a description of the provisions of the
with respect to the shares of Pioneer Parent common stock    partnership agreement of each partnership governing the
depend upon the performance of Pioneer Parent.               allocation of costs and revenues among the
                                                             partnership's partners, see Table 9 of Appendix A.
----------------------------------------------------------------------------------------------------------------------



                                  LEGAL MATTERS


     Vinson & Elkins L.L.P., counsel to Pioneer Parent, will pass upon the
validity of the Pioneer Parent common stock to be issued upon the merger of each
partnership and material federal income tax matters related to the merger of
each partnership. The limited partners' special legal counsel,         , Dallas,
Texas, will deliver the legal opinion referred to in "The Merger of Each
Partnership -- Legal Opinion for Limited Partners" on page 47 of this document.
That special counsel may rely as to matters of law of jurisdictions other than
the United States and the State of Texas on the opinion of counsel in such other
jurisdictions.


           INDEPENDENT AUDITORS AND INDEPENDENT PETROLEUM CONSULTANTS


     The consolidated financial statements of Pioneer Parent appearing in its
Annual Report (Form 10-K) for the year ended December 31, 2000, have been
audited by Ernst & Young LLP, independent auditors, as set forth in their
report, which is incorporated by reference into this document. Such consolidated
financial statements are incorporated by reference in reliance upon such report
given on the authority of such firm as experts in accounting and auditing.


     The financial statements of each partnership listed on pages 4 and 5 of
this document at December 31, 2000 and 1999 and for each of the three years in
the period ended December 31, 2000 have been audited by Ernst & Young

                                      -79-
   90


LLP, independent auditors, as set forth in their reports included in the
supplemental information to this document for each partnership. Such financial
statements are included in the supplemental information of each partnership in
reliance upon such reports given on the authority of such firm as experts in
accounting and auditing.


     Williamson Petroleum Consultants, Inc., independent petroleum consultants,
estimated each partnership's reserves as of December 31, 2000, and reviewed
Pioneer Parent's and Pioneer USA's estimates of each partnership's reserves as
of March 31, 2001 and the present value of the estimated future net revenues
from those estimated reserves included in the summary reserve reports included
in this document and such summary reserve reports and estimates and the review
as of March 31, 2001, are included in this document in reliance upon their
reports given upon their authority as experts on the matters covered by the
summary reserve report and review.





                                      -80-
   91


                         COMMONLY USED OIL AND GAS TERMS

     The definitions set forth below shall apply to the indicated terms as used
in this document. All volumes of natural gas referred to herein are stated at
the legal pressure base of the state or area where the reserves exist and at 60
degrees Fahrenheit and in most instances are rounded to the nearest major
multiple.

     "Bbl" means a standard barrel of 42 U.S. gallons and represents the basic
unit for measuring the production of crude oil, natural gas liquids and
condensate.

     "Bcf" means one billion cubic feet under prescribed conditions of pressure
and temperature and represents the basic unit for measuring the production of
natural gas.

     "BOE" means a barrel-of-oil-equivalent and is a customary convention used
in the United States to express oil and gas volumes on a comparable basis. It is
determined on the basis of the estimated relative energy content of natural gas
to oil, being approximately six Mcf of natural gas per Bbl of oil.

     "BTU" means British thermal unit.


     "development drilling" means drilling within the proved area of an oil or
gas reservoir to the depth of a stratigraphic horizon known to be productive.



     "exploration activity" means drilling activity to find and produce oil or
natural gas in an area that is not known to be an oil or natural gas reservoir,
or drilling activity to extend a known reservoir.


     "Mbbl" means one thousand Bbls.

     "MBOE" means one thousand BOEs.

     "Mcf" means one thousand cubic feet under prescribed conditions of pressure
and temperature and represents the basic unit for measuring the production of
natural gas.

     "MMBbl" means one million Bbls.

     "MMcf" means one million cubic feet under prescribed conditions of pressure
and temperature and represents the basic unit for measuring the production of
natural gas.

     "NGLs" means natural gas liquids.

     "proved reserves" means the estimated quantities of crude oil, natural gas,
and natural gas liquids which geological and engineering data demonstrate with
reasonable certainty to be recoverable in future years from known reservoirs
under existing economic and operating conditions, i.e., prices and costs as of
the date the estimate is made. Prices include consideration of changes in
existing prices provided only by contractual arrangements, but not on
escalations based upon future conditions.

               (i) Reservoirs are considered proved if economic producibility is
          supported by either actual production or conclusive formation test.
          The area of a reservoir considered proved includes (A) that portion
          delineated by drilling and defined by gas-oil and/or oil-water
          contacts, if any; and (B) the immediately adjoining portions not yet
          drilled, but which can be reasonably judged as economically productive
          on the basis of available geological and engineering data. In the
          absence of information on fluid contacts, the lowest known structural
          occurrence of hydrocarbons controls the power proved limit of the
          reservoir.

               (ii)Reserves which can be produced economically through
          application of improved recovery techniques (such as fluid injection)
          are included in the "proved" classification when successful testing by
          a pilot project, or the operation of an installed program in the
          reservoir, provides support for the engineering analysis on which the
          project or program was based.

               (iii) Estimates of proved reserves do not include the following:
          (A) oil that may become available from known reservoirs but is
          classified separately as "indicated additional reserves"; (B) crude
          oil, natural gas, and natural gas liquids, the recovery of which is
          subject to reasonable doubt because of uncertainty as to geology,
          reservoir characteristics, or economic factors; (C) crude oil, natural
          gas, and natural gas liquids, that may occur in undrilled prospects;
          and (D) crude oil, natural gas, and natural gas liquids, that may be
          recovered from oil shales, coal, gilsonite and other such sources.


                                      -81-
   92
                        PIONEER NATURAL RESOURCES COMPANY

                UNAUDITED PRO FORMA COMBINED FINANCIAL STATEMENTS

INTRODUCTORY STATEMENTS


     The unaudited pro forma combined financial statements of Pioneer Parent
have been prepared to give effect to Pioneer Parent's offer to acquire 46
limited partnerships (collectively, the "Combined Partnerships") that Pioneer
USA serves as the sole or managing general partner.

     The unaudited pro forma combined balance sheet of Pioneer Parent as of
March 31, 2001 has been prepared to give effect to the acquisition of the
Combined Partnerships as if it had occurred on March 31, 2001.

     The unaudited pro forma combined statements of operations of Pioneer Parent
for the three months ended March 31, 2001 and for the year ended December 31,
2000 have been prepared to give effect to the acquisition of the Combined
Partnerships as if it had occurred on January 1, 2000.

     The unaudited pro forma combined financial statements included herein are
not necessarily indicative of the results that might have occurred had the
transaction taken place on the dates that are assumed for the pro forma
presentations and are not intended to be a projection of future results. Future
results may vary significantly from the results reflected in the accompanying
unaudited pro forma combined financial statements because of normal production
declines, changes in product prices, future acquisitions and divestitures,
future development and exploration activities, and other factors.

     The following unaudited pro forma combined financial statements should be
read in conjunction with the Consolidated Financial Statements (and the related
notes) of Pioneer Parent included in the Annual Report on Form 10-K for the year
ended December 31, 2000, the Quarterly Report on Form 10-Q for the three months
ended March 31, 2001 and the historical financial statements of each partnership
in which you own an interest contained in the supplement to this document for
the partnership.





                                      P-1
   93



                        PIONEER NATURAL RESOURCES COMPANY


                   UNAUDITED PRO FORMA COMBINED BALANCE SHEET
                              AS OF MARCH 31, 2001
                        (IN THOUSANDS, EXCEPT SHARE DATA)





                                                        ASSETS

                                                      PIONEER         COMBINED           PRO FORMA         PRO FORMA
                                                       PARENT       PARTNERSHIPS        ADJUSTMENTS      PIONEER PARENT
                                                    ------------    ------------       ------------      --------------
                                                                                             
Current assets:
  Cash and cash equivalents .....................   $     18,305    $      5,153       $     (5,153)(c)   $     18,305
  Accounts receivable:
    Trade, net ..................................        102,437           7,362                               109,799
    Affiliates ..................................          1,479            --                 (929)(b)            550
  Inventories ...................................         12,965            --                                  12,965
  Deferred income taxes .........................          4,800            --                                   4,800
  Other current assets ..........................         18,242            --                                  18,242
                                                    ------------    ------------                          ------------
      Total current assets ......................        158,228          12,515                               164,661
                                                    ------------    ------------                          ------------

Property, plant and equipment, at cost:
  Oil and gas properties, using the successful
    efforts method of accounting:
        Proved properties........................      3,288,356         356,847           (255,941)(a)      3,389,262
        Unproved properties......................        216,322            --                                 216,322
  Accumulated depletion, depreciation and
    amortization ................................       (947,580)       (310,495)           310,495 (a)       (947,580)
                                                    ------------    ------------                          ------------
                                                       2,557,098          46,352                             2,658,004
                                                    ------------    ------------                          ------------

Deferred income taxes ...........................         85,200            --                                  85,200
Other property and equipment, net ...............         22,497            --                                  22,497
Other assets, net ...............................         99,185            --                                  99,185
                                                    ------------    ------------                          ------------
                                                    $  2,922,208    $     58,867                          $  3,029,547
                                                    ============    ============                          ============

                                         LIABILITIES AND STOCKHOLDERS' EQUITY
Current liabilities:
  Accounts payable:
    Trade .......................................   $    110,795    $         24       $      1,911 (c)   $    112,730
    Affiliates ..................................          1,802             929               (929)(b)          1,802
  Interest payable ..............................         38,863            --                                  38,863
  Other current liabilities:
    Derivative obligations ......................        109,118            --                                 109,118
    Other .......................................         50,713            --                                  50,713
                                                    ------------    ------------                          ------------
      Total current liabilities .................        311,291             953                               313,226
                                                    ------------    ------------                          ------------

Long-term debt, less current maturities .........      1,550,230            --                               1,550,230
Other noncurrent liabilities ....................        194,615            --                                 194,615
Deferred income taxes ...........................         25,100            --                                  25,100
Partners' capital ...............................           --            57,914            (57,914)(a)(c)        --
Stockholders' equity:
  Common stock ..................................          1,015            --                   59 (a)          1,074
  Additional paid-in capital ....................      2,354,778            --              105,345 (a)      2,460,123
  Treasury stock ................................        (44,752)           --                                 (44,752)
  Accumulated deficit ...........................     (1,354,784)           --                              (1,354,784)
  Accumulated other comprehensive income:
    Deferred hedge gains and losses .............       (110,507)           --                                (110,507)
    Unrealized gain on available for sale
      securities ................................          1,054            --                                   1,054
    Cumulative translation adjustment ...........         (5,832)           --                                  (5,832)
                                                    ------------    ------------                          ------------
      Total stockholders' equity and
         partners' capital ......................        840,972          57,914                               946,376
                                                    ------------    ------------                          ------------
Commitments and contingencies ...................   $  2,922,208    $     58,867                          $  3,029,547
                                                    ============    ============                          ============




         The accompanying notes are an integral part of these unaudited
                    pro forma combined financial statements.




                                      P-2
   94



                        PIONEER NATURAL RESOURCES COMPANY


              UNAUDITED PRO FORMA COMBINED STATEMENT OF OPERATIONS
                        THREE MONTHS ENDED MARCH 31, 2001
                      (IN THOUSANDS, EXCEPT PER SHARE DATA)





                                                                                                                 PRO FORMA
                                                           PIONEER         COMBINED            PRO FORMA          PIONEER
                                                            PARENT       PARTNERSHIPS         ADJUSTMENTS         PARENT
                                                         ------------    ------------       ---------------    ------------
                                                                                                   
Revenues:
  Oil and gas ........................................   $    257,986    $     13,727       $       (959)(d)   $    270,754
  Interest and other .................................          5,167             101                 (7)(d)          5,261
  Gain on disposition of assets, net .................          7,293              75               --                7,368
                                                         ------------    ------------                          ------------
                                                              270,446          13,903                               283,383
                                                         ------------    ------------                          ------------
Cost and expenses:
  Oil and gas production .............................         55,802           5,228                (83)(d)
                                                                                                  (1,414)(e)         59,533
  Depletion, depreciation and
    amortization .....................................         52,161             892                701 (f)         53,754
  Exploration and abandonments .......................         22,883              41               --               22,924
  General and administrative .........................         10,448             445                (25)(d)
                                                                                                   1,414 (e)         12,282
  Interest ...........................................         35,616            --                                  35,616
  Other ..............................................         25,217            --                                  25,217
                                                         ------------    ------------                          ------------
                                                              202,127           6,606                               209,326
                                                         ------------    ------------                          ------------

Income from continuing operations before
   income taxes ......................................         68,319           7,297                                74,057
Income tax benefit ...................................           (400)           --                 --   (h)           (400)
                                                         ------------    ------------                          ------------
Income from continuing operations ....................   $     67,919    $      7,297                          $     73,657
                                                         ============    ============                          ============

Income from continuing operations per common share:
    Basic ............................................   $        .69                                          $        .71
                                                         ============                                          ============
    Diluted ..........................................   $        .68                                          $        .70
                                                         ============                                          ============
Weighted average shares outstanding:
    Basic ............................................         98,379                              5,856 (i)        104,235
                                                         ============                                          ============
    Diluted ..........................................         99,708                              5,856 (i)        105,564
                                                         ============                                          ============




                  See accompanying notes to unaudited pro forma
                         combined financial statements.



                                      P-3
   95


                        PIONEER NATURAL RESOURCES COMPANY



              UNAUDITED PRO FORMA COMBINED STATEMENT OF OPERATIONS
                          YEAR ENDED DECEMBER 31, 2000
                      (IN THOUSANDS, EXCEPT PER SHARE DATA)





                                                     PIONEER            COMBINED            PRO FORMA           PRO FORMA
                                                      PARENT          PARTNERSHIPS         ADJUSTMENTS        PIONEER PARENT
                                                   -------------    -----------------    -----------------    ---------------
                                                                                                     
Revenues:
  Oil and gas...............................       $    852,738       $       52,013      $   (3,369)(d)         $   901,382
  Interest and other........................             25,775                  484             (28)(d)              26,231
  Gain on disposition of assets, net........             34,184                  247              (6)(d)              34,425
                                                   ------------       --------------                             -----------
                                                        912,697               52,744                                 962,038
                                                   ------------       --------------                             -----------
Cost and expenses:
  Oil and gas production....................            189,265               19,958          (1,392)(d)
                                                                                              (5,655)(e)             202,176
  Depletion, depreciation and
    amortization............................            214,938                3,236           3,768 (f)             221,942
  Impairment of oil and gas properties......                 --                  663            (663)(g)                --
  Exploration and abandonments..............             87,550                   72              (3)(d)              87,619
  General and administrative................             33,262                1,599            (110)(d)
                                                                                               5,655 (e)              40,406
  Interest..................................            161,952                   --                                 161,952
  Other.....................................             67,231                   --                                  67,231
                                                   ------------       --------------                             -----------
                                                        754,198               25,528                                 781,326
                                                   ------------       --------------                             -----------

Income from continuing operations before
   income taxes.............................            158,499               27,216                                 180,712
Income tax benefit..........................              6,000                   --              -- (h)               6,000
                                                   ------------       --------------                             -----------
Income from continuing operations...........       $    164,499       $       27,216                             $   186,712
                                                   ============       ==============                             ===========

Income from continuing operations per
   common share:
    Basic...................................       $       1.65                                                  $      1.77
                                                   ============                                                  ===========
    Diluted.................................       $       1.65                                                  $      1.77
                                                   ============                                                  ===========
Weighted average shares outstanding:
    Basic...................................             99,378                                5,856(i)              105,234
                                                   ============                                                  ===========
    Diluted.................................             99,762                                5,856(i)              105,618
                                                   ============                                                  ===========




                  See accompanying notes to unaudited pro forma
                         combined financial statements.



                                      P-4
   96
                        PIONEER NATURAL RESOURCES COMPANY


                      NOTES TO UNAUDITED PRO FORMA COMBINED
                              FINANCIAL STATEMENTS
                      MARCH 31, 2001 AND DECEMBER 31, 2000



NOTE 1.  BASIS OF PRESENTATION


     The unaudited pro forma combined financial information of Pioneer Natural
Resources Company ("Pioneer Parent") has been prepared to give effect to Pioneer
Parent's offer to acquire 46 limited partnerships (collectively, the "Combined
Partnerships") that Pioneer USA serves as the sole or managing general partner.
The unaudited pro forma combined balance sheet as of March 31, 2001 has been
prepared to give effect to the acquisition of the Combined Partnerships as if it
had occurred on March 31, 2001. The unaudited pro forma combined statements of
operations for the three months ended March 31, 2001 and for the year ended
December 31, 2000 are presented as if the acquisition of the Combined
Partnerships occurred on January 1, 2000.


     Following is a description of the individual columns included in these
unaudited pro forma combined financial statements:


     Pioneer Parent - Represents the consolidated balance sheet of Pioneer
  Parent as of March 31, 2001, and the consolidated statements of operations of
  Pioneer Parent for the three months ended March 31, 2001 and the year ended
  December 31, 2000.



     Combined Partnerships - Represents the combined balance sheets of the 46
  limited partnerships as of March 31, 2001 and the combined statements of
  operations of such limited partnerships for the three months ended March 31,
  2001 and the year ended December 31, 2000.


NOTE 2.  PRO FORMA ADJUSTMENTS

     Following are descriptions of the pro forma adjustments used in the
preparation of the accompanying unaudited pro forma combined financial
statements:


  (a)  To record the acquisition of the Combined Partnerships, using the
       purchase method of accounting, for $105.4 million in Pioneer common
       stock, representing 5,855,813 shares assuming an $18.00 average stock
       price. The allocation of the purchase price to the acquired assets and
       liabilities is preliminary and, therefore, subject to change.



       The purchase price allocation as of March 31, 2001 reflects the fair
       value of the Combined Partnerships' assets and liabilities as of that
       date. A final purchase price allocation will be done at closing based
       upon the fair value of the Combined Partnerships' assets and liabilities
       at that time. The date three business days prior to the special meeting
       of limited partners of each partnership to be held on , 2001 will be the
       measurement date for determining the final number of shares of Pioneer
       Parent common stock to be issued (the "Measurement Date"). Pioneer Parent
       will value the shares to be issued using the average closing price of
       Pioneer Parent common stock for the five-day period comprised of the two
       days prior to the Measurement Date, the Measurement Date and the two
       business days subsequent to the Measurement Date. The final allocation is
       not anticipated to change materially other than for cash flow generated
       from the Combined Partnerships' property interests between March 31, 2001
       and closing, which will be reflected as a reduction to oil and gas
       properties and an increase to working capital in the final purchase price
       allocation.



  (b)  To eliminate affiliate receivables and affiliate payables between Pioneer
       Parent and the Combined Partnerships.



  (c)  To adjust pro forma cash, accounts payable and partners' capital for the
       $7.1 million cash distribution that will be disbursed to existing
       partners other than Pioneer USA during July 2001.



  (d)  To eliminate Pioneer Parent's proportionate share of the Combined
       Partnerships that is already reflected in Pioneer Parent's consolidated
       statements of operations for the three months ended March 31, 2001 and
       for the year ended December 31, 2000.



                                      P-5
   97
                        PIONEER NATURAL RESOURCES COMPANY


                      NOTES TO UNAUDITED PRO FORMA COMBINED
                              FINANCIAL STATEMENTS
                      MARCH 31, 2001 AND DECEMBER 31, 2000




  (e)  To eliminate the Combined Partnership's share of operating overhead
       charged by Pioneer Parent that was recorded by the Combined Partnerships
       as an increase in lease operating expenses and by Pioneer Parent as a
       reduction to general and administrative expense.



  (f)  To adjust depreciation, depletion and amortization expense for the basis
       allocated to the oil and gas properties acquired and accounted for using
       the successful efforts method of accounting.



  (g)  To eliminate the Combined Partnerships impairment of oil and gas
       properties that would not occur on a pro forma basis with Pioneer Parent
       due to the basis in oil and gas properties reflecting the value assigned
       using the purchase method of accounting.



  (h)  Pioneer Parent has unused net operating loss carryovers in the United
       States that could be used to offset any incremental earnings of the
       Combined Partnerships. Accordingly, no pro forma adjustment was recorded
       for additional income tax expense. See Note 3. below.



  (i)  To adjust the weighted average basic and diluted common shares
       outstanding for the issuance of 5,855,813 shares of Pioneer Parent common
       stock to acquire the Combined Partnerships.



       The pro forma numerator for basic and diluted earnings per share
       calculations equals "income from continuing operations" per the Unaudited
       Pro Forma Combined Statement of Operations (see page P-3). Following is a
       reconciliation of the pro forma weighted average basic and diluted shares
       outstanding (in thousands):





                                                             March 31, 2001      December 31, 2000
                                                             --------------      -----------------
                                                                           
        Pioneer Parent weighted average basic common
        shares outstanding...............................         98,379                 99,378

        Shares offered attributable to the additional
        nonmanaging general partners' interests..........             11                     11

        Shares offered attributable to the additional
        limited partners' interests......................          5,845                  5,845
                                                               ---------              ---------
        Pro forma Pioneer Parent weighted average basic
        shares outstanding...............................        104,235                105,234

        Effect of dilutive common stock options..........          1,329                    384
                                                               ---------              ---------
        Pro forma Pioneer Parent weighted average diluted
        shares outstanding...............................        105,564                105,618
                                                               =========              =========



NOTE 3.  INCOME TAXES


     Pioneer Parent will account for income taxes in accordance with the
provisions of Statement of Financial Accounting Standards No. 109, "Accounting
for Income Taxes". In accordance therewith, Pioneer Parent will prepare separate
tax calculations for each tax jurisdiction in which Pioneer Parent will be
subject to income taxes. Pioneer Parent has unused net operating loss carryovers
and alternative minimum tax net operating loss carryovers that would be utilized
to reduce incremental United States income taxes that would otherwise be
incurred as a result of pro forma pre-tax earnings of the Combined Partnerships.
Accordingly, Pioneer Parent has not recognized incremental income tax expense in
the accompanying unaudited pro forma combined statements of operations for the
three months ended March 31, 2001 and the year ended December 31, 2000.


NOTE 4.  OIL AND GAS RESERVE DATA


     The following unaudited pro forma supplemental information regarding the
oil and gas activities of Pioneer Parent is presented pursuant to the disclosure
requirements promulgated by the Securities and Exchange Commission and Statement
of Financial Accounting Standards No. 69, "Disclosures About Oil and Gas
Producing Activities". The pro forma combined reserve information is presented
as if the acquisition of the Combined Partnerships had occurred on January 1,
2000. Information for oil and NGL's are presented in barrels (Bbls) and for gas
in thousands of cubic feet (Mcf).




                                      P-6
   98
                        PIONEER NATURAL RESOURCES COMPANY


                      NOTES TO UNAUDITED PRO FORMA COMBINED
                              FINANCIAL STATEMENTS
                      MARCH 31, 2001 AND DECEMBER 31, 2000




     Pioneer Parent emphasizes that reserve estimates are inherently imprecise
and subject to revision and that estimates of new discoveries are more imprecise
than those of producing oil and gas properties. Accordingly, the estimates are
expected to change as future information becomes available and such changes
could be significant.



     For additional information regarding the oil and gas activities of Pioneer
Parent and the Combined Partnerships, from which the following unaudited pro
forma supplemental information was derived, please see: (a) Pioneer Parent's
Annual Report on Form 10-K for the year ended December 31, 2000 for information
regarding Pioneer Parent's stand-alone oil and gas activities, (b) Table 11 of
Appendix A and (c) the review by Williamson Petroleum Consultants, Inc. of the
Summary Reserve Report for the Combined Partnerships included in Appendix B for
the volumes and values attributable to the Combined Partnerships.





                                      P-7
   99
                        PIONEER NATURAL RESOURCES COMPANY


                      NOTES TO UNAUDITED PRO FORMA COMBINED
                              FINANCIAL STATEMENTS
                      MARCH 31, 2001 AND DECEMBER 31, 2000



QUANTITIES OF OIL AND GAS RESERVES

     Set forth below is a pro forma summary of the changes in the net quantities
of oil, NGL and natural gas reserves for the year ended December 31, 2000.




                                        OIL
                                        & NGLs         GAS
                                       (MBbls)        (MMcf)         MBOE
                                      ----------    ----------    ----------
                                                         
TOTAL PROVED RESERVES:

UNITED STATES
Balance, January 1 ................      290,683     1,365,530       518,271
Revisions of previous estimates ...       18,704        54,518        27,790
Purchases of minerals-in-place ....        1,237        28,071         5,916
New discoveries and extensions ....        4,819        66,486        15,900
Production ........................      (18,571)      (86,206)      (32,939)
Sales of minerals-in-place ........         (743)      (35,054)       (6,586)
                                      ----------    ----------    ----------
Balance, December 31 ..............      296,129     1,393,345       528,352


ARGENTINA
Balance, January 1 ................       29,797       415,620        99,067
Revisions of previous estimates ...        1,411       (15,558)       (1,182)
Purchases of minerals-in-place ....         --            --            --
New discoveries and extensions ....        8,066        43,914        15,385
Production ........................       (3,431)      (35,694)       (9,380)
Sales of minerals-in-place ........         --            --            --
                                      ----------    ----------    ----------
Balance, December 31 ..............       35,843       408,282       103,890

CANADA
Balance, January 1 ................        3,970       145,251        28,179
Revisions of previous estimates ...          429       (10,013)       (1,240)
Purchases of minerals-in-place ....          140         7,768         1,435
New discoveries and extensions ....          138         6,132         1,160
Production ........................         (611)      (16,219)       (3,315)
Sales of minerals-in-place ........         --            --            --
                                      ----------    ----------    ----------
Balance, December 31 ..............        4,066       132,919        26,219

SOUTH AFRICA
Balance, January 1 ................         --            --            --
New discoveries and extensions ....        5,552          --           5,552
                                      ----------    ----------    ----------
Balance, December 31 ..............        5,552          --           5,552

TOTAL
Balance, January 1 ................      324,450     1,926,401       645,517
Revisions of previous estimates ...       20,544        28,947        25,368
Purchases of minerals-in-place ....        1,377        35,839         7,351
New discoveries and extensions ....       18,575       116,532        37,997
Production ........................      (22,613)     (138,119)      (45,634)
Sales of minerals-in-place ........         (743)      (35,054)       (6,586)
                                      ----------    ----------    ----------
Balance, December 31 ..............      341,590     1,934,546       664,013
                                      ==========    ==========    ==========

PROVED DEVELOPED RESERVES:
  United States ...................      241,253     1,169,664       436,198
  Argentina .......................       22,931       358,124        82,618
  Canada ..........................        2,598        61,210        12,800
                                      ----------    ----------    ----------
    January 1 .....................      266,782     1,588,998       531,616
                                      ==========    ==========    ==========

  United States ...................      236,249     1,120,610       423,018
  Argentina .......................       22,679       345,281        80,226
  Canada ..........................        2,930        80,953        16,422
                                      ----------    ----------    ----------
    December 31 ...................      261,858     1,546,844       519,666
                                      ==========    ==========    ==========






                                      P-8
   100
                        PIONEER NATURAL RESOURCES COMPANY


                      NOTES TO UNAUDITED PRO FORMA COMBINED
                              FINANCIAL STATEMENTS
                      MARCH 31, 2001 AND DECEMBER 31, 2000



STANDARDIZED MEASURE OF DISCOUNTED FUTURE NET CASH FLOWS

     The pro forma standardized measure of discounted future net cash flow is
computed by applying year-end prices of oil and gas (with consideration of price
changes only to the extent provided by contractual arrangements) to the
estimated future production of oil and gas reserves less estimated future
expenditures (based on year-end costs) to be incurred in developing and
producing the proved reserves discounted using a rate of 10 percent per year to
reflect the estimated timing of the future cash flows. Future income taxes are
calculated by comparing undiscounted future cash flows to the tax basis of oil
and gas properties plus available carryforwards and credits and applying the
current tax rate to the difference.



                                                                DECEMBER 31, 2000
                                                                -----------------
                                                                 (IN THOUSANDS)
                                                              
UNITED STATES
Oil and gas producing activities:
  Future cash inflows ........................................   $ 19,615,577
  Future production costs ....................................     (5,290,990)
  Future development costs ...................................       (479,290)
  Future income tax expenses .................................     (3,945,569)
                                                                 ------------
                                                                    9,899,728
  10% annual discount factor .................................     (4,991,172)
                                                                 ------------
  Standardized measure of discounted future net cash flows ...   $  4,908,556
                                                                 ============

ARGENTINA
Oil and gas producing activities:
  Future cash inflows ........................................   $  1,183,652
  Future production costs ....................................       (215,853)
  Future development costs ...................................       (114,606)
  Future income tax expenses .................................        (81,705)
                                                                 ------------
                                                                      771,488
  10% annual discount factor .................................       (264,126)
                                                                 ------------
  Standardized measure of discounted future net cash flows ...   $    507,362
                                                                 ============

CANADA
Oil and gas producing activities:
  Future cash inflows ........................................   $  1,029,007
  Future production costs ....................................       (104,189)
  Future development costs ...................................        (35,443)
  Future income tax expenses .................................       (306,399)
                                                                 ------------
                                                                      582,976
  10% annual discount factor .................................       (168,441)
                                                                 ------------
  Standardized measure of discounted future net cash flows ...   $    414,535
                                                                 ============

SOUTH AFRICA
Oil and gas producing activities:
  Future cash inflows ........................................   $    126,134
  Future production costs ....................................        (65,232)
  Future development costs ...................................        (47,970)
  Future income tax expenses .................................           --
                                                                 ------------
                                                                       12,932
  10% annual discount factor .................................         (5,782)
                                                                 ------------
  Standardized measure of discounted future net cash flows ...   $      7,150
                                                                 ============

TOTAL
Oil and gas producing activities:
  Future cash inflows ........................................   $ 21,954,370
  Future production costs ....................................     (5,676,264)
  Future development costs ...................................       (677,309)
  Future income tax expenses .................................     (4,333,673)
                                                                 ------------
                                                                   11,267,124
  10% annual discount factor .................................     (5,429,521)
                                                                 ------------
  Standardized measure of discounted future net cash flows ...   $  5,837,603
                                                                 ============




                                      P-9
   101
                        PIONEER NATURAL RESOURCES COMPANY


                      NOTES TO UNAUDITED PRO FORMA COMBINED
                              FINANCIAL STATEMENTS
                      MARCH 31, 2001 AND DECEMBER 31, 2000



CHANGES RELATING TO THE PRO FORMA STANDARDIZED MEASURE OF DISCOUNTED FUTURE NET
CASH FLOWS

     The principal sources of the change in the pro forma combined standardized
measure of discounted future net cash flows for the year ended December 31, 2000
are as follows (in thousands):



                                                                             
                Oil and gas sales, net of production costs................      $    (699,206)
                Net changes in prices and production costs................          3,920,249
                Extension and discoveries.................................            525,361
                Development costs incurred during the period..............            101,350
                Sales of minerals-in-place................................            (72,624)
                Purchases of mineral-in-place.............................            187,097
                Revisions of estimated future development costs...........           (200,734)
                Revisions of previous quantity estimates..................            329,124
                Accretion of discount.....................................            313,281
                Changes in production rates, timing and other.............           (270,400)
                                                                                -------------
                Change in present value of future net revenues............          4,133,498
                Net change in present value of future income taxes........         (1,428,700)
                                                                                -------------
                                                                                    2,704,798
                Balance, beginning of year................................          3,132,805
                                                                                -------------
                Balance, end of year......................................      $   5,837,603
                                                                                =============








                                      P-10
   102
                                   APPENDIX A

                                       TO

                           PROXY STATEMENT/PROSPECTUS

                GENERAL INFORMATION RELATING TO EACH PARTNERSHIP


Table 1   Jurisdiction of Organization, Initial Subscription Price for Each
          Unit, Initial Investment by Limited Partners and Number of Limited
          Partners as of March 31, 2001


Table 2   Merger Value Attributable to Pioneer USA, Nonmanaging General
          Partners and Limited Partners



Table 3   Merger Value Attributable to Partnership Interests of Limited
          Partners Per $1,000 Investment



Table 4   Ownership Percentage and Merger Value Attributable to Nonmanaging
          General Partners Other Than Pioneer USA



Table 5   Ownership Percentage and Merger Value Attributable to Pioneer USA
          in Its Capacities as General Partner, Nonmanaging General Partner and
          Limited Partner


Table 6   Voting Percentage and Initial Investment Owned by Pioneer USA in
          Its Capacity as a Limited Partner as of March 31, 2001


Table 7   Historical Quarterly Partnership Distributions to the Limited
          Partners Per $1,000 Investment from Inception through July 31, 2001


Table 8   Annual Repurchase Prices and Aggregate Annual Repurchase Payments

Table 9   Participation in Costs and Revenues of Each Partnership

Table 10  Average Oil, Natural Gas Liquids and Gas Sales Prices and
          Production Costs for the Three Months Ended March 31, 2001 and 2000
          and the Years Ended December 31, 2000, 1999 and 1998

Table 11  Proved Reserves Attributable to Pioneer USA, Nonmanaging General
          Partners and Limited Partners as of December 31, 2000


Table 12  Partnership Estimated Reserves Attributable to Pioneer USA,
          Nonmanaging General Partners and Limited Partners as of March 31, 2001


Table 13  Oil, Natural Gas Liquids and Gas Production for the Three Months
          Ended March 31, 2001 and 2000 and the Years Ended December 31, 2000,
          1999 and 1998


Table 14  Productive Wells and Developed Acreage as of March 31, 2001


Table 15  Recent Trades of Partnership Interests Per $1,000 Investments for
          the Three Months Ended March 31, 2001 and the Years Ended December 31,
          2000 and 1999


Table 16  Reserve Value Attributable to Pioneer USA, Nonmanaging General
          Partners and Limited Partners as of March 31, 2001





                                      A-1
   103



                                     TABLE 1

     JURISDICTION OF ORGANIZATION, INITIAL SUBSCRIPTION PRICE FOR EACH UNIT,
      INITIAL INVESTMENT BY LIMITED PARTNERS AND NUMBER OF LIMITED PARTNERS
                              AS OF MARCH 31, 2001






                                                                                                 INITIAL
                                                                               INITIAL          INVESTMENT
                                                                             SUBSCRIPTION       BY LIMITED           NUMBER OF
                                                          JURISDICTION OF      PRICE FOR         PARTNERS             LIMITED
                                                            ORGANIZATION       EACH UNIT      (IN THOUSANDS)          PARTNERS
                                                          ---------------   --------------    ---------------       -----------
                                                                                                        
PARKER & PARSLEY 81-I, LTD.                                         Texas   $         5,000   $         7,410               135
PARKER & PARSLEY 81-II, LTD.                                        Texas             5,000             6,440               158
PARKER & PARSLEY 82-I, LTD.                                         Texas             2,000            11,805               606
PARKER & PARSLEY 82-II, LTD.                                        Texas             2,000            12,252               770
PARKER & PARSLEY 82-III, LTD.                                       Texas             2,000             6,882               418
PARKER & PARSLEY 83-A, LTD.                                         Texas             1,000            19,505             1,269
PARKER & PARSLEY 83-B, LTD.                                         Texas             1,000            23,370             1,374
PARKER & PARSLEY 84-A, LTD.                                         Texas             1,000            19,435             1,244
PARKER & PARSLEY 85-A, LTD.                                         Texas             1,000             9,613               796
PARKER & PARSLEY 85-B, LTD.                                         Texas             1,000             7,988               717
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.                      Texas            40,000             5,000               107
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.               Texas            40,000             4,690                79
PARKER & PARSLEY 86-A, LTD.                                         Texas             1,000            10,131               962
PARKER & PARSLEY 86-B, LTD.                                         Texas             1,000            17,208             1,390
PARKER & PARSLEY 86-C, LTD.                                         Texas             1,000            19,317             1,327
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                        Texas            40,000             4,920               103
PARKER & PARSLEY 87-A CONV., LTD.                                   Texas             1,000             3,856               214
PARKER & PARSLEY 87-A, LTD.                                         Texas             1,000            28,811             2,132
PARKER & PARSLEY 87-B CONV., LTD.                                   Texas             1,000             4,919               259
PARKER & PARSLEY 87-B, LTD.                                         Texas             1,000            20,089             1,464
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.                    Texas               500            12,213             1,098
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.                    Texas               500             6,096               549
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                        Texas            40,000            10,480               197
PARKER & PARSLEY 88-A CONV., L.P.                                Delaware             1,000             3,793               236
PARKER & PARSLEY 88-A, L.P.                                      Delaware             1,000            12,935               981
PARKER & PARSLEY 88-B CONV., L.P.                                Delaware             1,000             3,636               240
PARKER & PARSLEY 88-B, L.P.                                      Delaware             1,000             8,954               690
PARKER & PARSLEY 88-C CONV., L.P.                                Delaware             1,000             3,411               219
PARKER & PARSLEY 88-C, L.P.                                      Delaware             1,000             2,431               191
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.                 Delaware               500             5,611               507
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                     Delaware            40,000             9,960               153
PARKER & PARSLEY 89-A CONV., L.P.                                Delaware             1,000             2,797               191
PARKER & PARSLEY 89-A, L.P.                                      Delaware             1,000             8,317               608
PARKER & PARSLEY 89-B CONV., L.P.                                Delaware             1,000             6,307               341
PARKER & PARSLEY 89-B, L.P.                                      Delaware             1,000             6,949               460
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                     Delaware            40,000             7,060               128
PARKER & PARSLEY 90-A CONV., L.P.                                Delaware             1,000             2,359               139
PARKER & PARSLEY 90-A, L.P.                                      Delaware             1,000             6,811               525
PARKER & PARSLEY 90-B CONV., L.P.                                Delaware             1,000            11,897               664
PARKER & PARSLEY 90-B, L.P.                                      Delaware             1,000            32,264             2,195
PARKER & PARSLEY 90-C CONV., L.P.                                Delaware             1,000             7,531               505
PARKER & PARSLEY 90-C, L.P.                                      Delaware             1,000            12,107               886
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                     Delaware            40,000            10,970               197
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.                 Delaware            40,000             5,200               105
PARKER & PARSLEY 91-A, L.P.                                      Delaware             1,000            11,620               725
PARKER & PARSLEY 91-B, L.P.                                      Delaware             1,000            11,249               681
                                                                                                                ---------------
                               TOTAL                                                                                     28,935
                                                                                                                ===============




                                       A-2
   104




                                     TABLE 2

              MERGER VALUE ATTRIBUTABLE TO PIONEER USA, NONMANAGING
                    GENERAL PARTNERS AND LIMITED PARTNERS (a)






                                                                          NONMANAGING
                                                                            GENERAL        LIMITED
                                                         PIONEER USA (b)  PARTNERS (c)   PARTNERS (d)      TOTAL
                                                         --------------   ------------   ------------   ------------
                                                                                            
PARKER & PARSLEY 81-I, LTD.                                $    225,691   $     16,187   $    628,935   $    870,813
PARKER & PARSLEY 81-II, LTD.                                    142,209          5,774        469,750        617,733
PARKER & PARSLEY 82-I, LTD.                                     384,588         13,293        843,604      1,241,485
PARKER & PARSLEY 82-II, LTD.                                    417,948         12,957      1,198,982      1,629,887
PARKER & PARSLEY 82-III, LTD.                                   305,950          9,928        787,723      1,103,601
PARKER & PARSLEY 83-A, LTD.                                     940,944         37,001      2,662,986      3,640,931
PARKER & PARSLEY 83-B, LTD.                                   1,233,793         48,095      3,472,973      4,754,861
PARKER & PARSLEY 84-A, LTD.                                   1,285,776         56,545      3,830,437      5,172,758
PARKER & PARSLEY 85-A, LTD.                                      41,068           --        1,362,562      1,403,630
PARKER & PARSLEY 85-B, LTD.                                      20,207           --        1,155,401      1,175,608
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.                   50,076           --        1,433,225      1,483,301
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.            24,401           --          883,142        907,543
PARKER & PARSLEY 86-A, LTD.                                      24,320           --        1,787,869      1,812,189
PARKER & PARSLEY 86-B, LTD.                                      67,657           --        3,828,747      3,896,404
PARKER & PARSLEY 86-C, LTD.                                      41,133           --        3,104,794      3,145,927
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                     12,640           --        1,251,314      1,263,954
PARKER & PARSLEY 87-A CONV., LTD.                                14,150           --          731,138        745,288
PARKER & PARSLEY 87-A, LTD.                                      88,920           --        5,463,944      5,552,864
PARKER & PARSLEY 87-B CONV., LTD.                                12,012           --          987,950        999,962
PARKER & PARSLEY 87-B, LTD.                                      49,926           --        4,036,481      4,086,407
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.                 35,132           --        2,569,999      2,605,131
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.                 62,154           --        2,336,072      2,398,226
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                     29,502           --        2,920,727      2,950,229
PARKER & PARSLEY 88-A CONV., L.P.                                21,672           --          918,526        940,198
PARKER & PARSLEY 88-A, L.P.                                      74,684           --        3,138,812      3,213,496
PARKER & PARSLEY 88-B CONV., L.P.                                18,200           --        1,160,138      1,178,338
PARKER & PARSLEY 88-B, L.P.                                      59,211           --        2,844,288      2,903,499
PARKER & PARSLEY 88-C CONV., L.P.                                12,256           --          937,636        949,892
PARKER & PARSLEY 88-C, L.P.                                       8,093           --          664,276        672,369
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.                 34,210           --        1,992,312      2,026,522
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                     34,558           --        3,421,198      3,455,756
PARKER & PARSLEY 89-A CONV., L.P.                                 9,323           --          922,978        932,301
PARKER & PARSLEY 89-A, L.P.                                      62,481           --        2,714,640      2,777,121
PARKER & PARSLEY 89-B CONV., L.P.                                23,671           --        1,777,880      1,801,551
PARKER & PARSLEY 89-B, L.P.                                      40,152           --        1,941,940      1,982,092
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                     30,131           --        1,900,223      1,930,354
PARKER & PARSLEY 90-A CONV., L.P.                                 9,110           --          564,755        573,865
PARKER & PARSLEY 90-A, L.P.                                      52,103           --        1,608,971      1,661,074
PARKER & PARSLEY 90-B CONV., L.P.                                53,040           --        3,131,176      3,184,216
PARKER & PARSLEY 90-B, L.P.                                     108,517           --        8,540,497      8,649,014
PARKER & PARSLEY 90-C CONV., L.P.                                25,877           --        1,829,980      1,855,857
PARKER & PARSLEY 90-C, L.P.                                      36,317           --        2,938,575      2,974,892
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                     53,018           --        3,386,441      3,439,459
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.                 15,154           --        1,500,276      1,515,430
PARKER & PARSLEY 91-A, L.P.                                      65,151           --        4,644,353      4,709,504
PARKER & PARSLEY 91-B, L.P.                                      54,733           --        4,975,820      5,030,553




----------

(a)      The merger value for each partnership is equal to the sum of the
         present value of estimated future net revenues from the partnership's
         estimated oil and gas reserves and its net working capital in each case
         as of March 31, 2001, less its pro rata share, based on its reserve
         value, of the estimated expenses and fees of the mergers of all of the
         partnerships and less the cash distribution on or about July 9, 2001,
         by the partnership to its partners.

(b)      Represents Pioneer USA's partnership interests in each partnership as:
         (1) the sole or managing general partner of the partnership; (2) a
         limited partner of the partnership; and (3) the sole general partner of
         each nonmanaging general partner. Pioneer USA will not receive any
         Pioneer common stock or cash payment for its partnership interests in
         any participating partnership. However, as a result of the merger of
         each participating partnership, Pioneer USA will own 100% of the
         properties of the partnership including properties attributable to its
         partnership interests in the partnership.

(c)      Represents four unaffiliated individuals' partnership interests as
         limited partners of each nonmanaging general partner. Excludes Pioneer
         USA's partnership interests as general partner of each nonmanaging
         general partner.

(d)      Represents the partnership interests of unaffiliated limited partners
         of each partnership. Excludes Pioneer USA's partnership interests as a
         limited partner of any partnership.


                                      A-3
   105



                                     TABLE 3

               MERGER VALUE ATTRIBUTABLE TO PARTNERSHIP INTERESTS
                               OF LIMITED PARTNERS
                              PER $1,000 INVESTMENT





                                                                                  LIMITED PARTNERS
                                                                                PER $1,000 INVESTMENT
                                                      ---------------------------------------------------------------------------
                                                                                              AGGREGATE        LESS
                                                       RESERVE  WORKING CAPITAL    EXPENSES     MERGER      JULY 2001     MERGER
                                                        VALUE       VALUE          AND FEES      VALUE    DISTRIBUTIONS   VALUE
                                                      --------- ---------------   ---------    ---------  ------------- ---------
                                                                                                      
PARKER & PARSLEY 81-I, LTD.                           $   89.88   $    9.32       $   (1.64)   $   97.56   $   (7.43)   $   90.13
PARKER & PARSLEY 81-II, LTD.                              70.80       10.16           (1.29)       79.67       (6.33)       73.34
PARKER & PARSLEY 82-I, LTD.                               79.20        9.69           (1.44)       87.45       (7.39)       80.06
PARKER & PARSLEY 82-II, LTD.                              98.62        9.83           (1.80)      106.65       (5.04)      101.61
PARKER & PARSLEY 82-III, LTD.                            121.37       10.28           (2.21)      129.44       (7.72)      121.72
PARKER & PARSLEY 83-A, LTD.                              137.31       15.18           (2.50)      149.99       (8.56)      141.43
PARKER & PARSLEY 83-B, LTD.                              148.27       17.04           (2.70)      162.61       (8.20)      154.41
PARKER & PARSLEY 84-A, LTD.                              196.55       20.97           (3.58)      213.94      (12.51)      201.43
PARKER & PARSLEY 85-A, LTD.                              140.29       16.15           (2.56)      153.88       (9.33)      144.55
PARKER & PARSLEY 85-B, LTD.                              140.24       17.78           (2.56)      155.46       (9.76)      145.70
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.           290.83       24.78           (5.30)      310.31      (16.62)      293.69
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.    191.78       20.14           (3.50)      208.42      (16.85)      191.57
PARKER & PARSLEY 86-A, LTD.                              170.64       10.64           (3.11)      178.17       (1.08)      177.09
PARKER & PARSLEY 86-B, LTD.                              218.42       22.98           (3.98)      237.42      (13.25)      224.17
PARKER & PARSLEY 86-C, LTD.                              157.16       21.31           (2.86)      175.61      (14.38)      161.23
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.             251.34       24.39           (4.58)      271.15      (16.82)      254.33
PARKER & PARSLEY 87-A CONV., LTD.                        185.77       24.00           (3.39)      206.38      (15.03)      191.35
PARKER & PARSLEY 87-A, LTD.                              184.98       24.23           (3.37)      205.84      (15.03)      190.81
PARKER & PARSLEY 87-B CONV., LTD.                        193.71       23.92           (3.53)      214.10      (12.85)      201.25
PARKER & PARSLEY 87-B, LTD.                              193.71       24.05           (3.53)      214.23      (12.85)      201.38
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.         203.00       32.10           (3.70)      231.40      (20.23)      211.17
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.         389.13       26.85           (7.09)      408.89      (19.38)      389.51
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.             280.46       23.09           (5.11)      298.44      (19.75)      278.69
PARKER & PARSLEY 88-A CONV., L.P.                        238.46       31.69           (4.35)      265.80      (20.40)      245.40
PARKER & PARSLEY 88-A, L.P.                              238.46       32.24           (4.35)      266.35      (20.40)      245.95
PARKER & PARSLEY 88-B CONV., L.P.                        314.31       30.88           (5.73)      339.46      (18.63)      320.83
PARKER & PARSLEY 88-B, L.P.                              314.31       31.07           (5.73)      339.65      (18.63)      321.02
PARKER & PARSLEY 88-C CONV., L.P.                        268.92       28.93           (4.90)      292.95      (17.26)      275.69
PARKER & PARSLEY 88-C, L.P.                              268.92       27.05           (4.90)      291.07      (17.26)      273.81
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.         325.76       58.49           (5.94)      378.31      (20.76)      357.55
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.             337.43       32.64           (6.15)      363.92      (20.42)      343.50
PARKER & PARSLEY 89-A CONV., L.P.                        323.16       33.65           (5.89)      350.92      (20.93)      329.99
PARKER & PARSLEY 89-A, L.P.                              323.16       34.23           (5.89)      351.50      (20.93)      330.57
PARKER & PARSLEY 89-B CONV., L.P.                        275.97       30.92           (5.03)      301.86      (19.07)      282.79
PARKER & PARSLEY 89-B, L.P.                              275.45       31.03           (5.02)      301.46      (19.07)      282.39
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.             266.72       27.07           (4.86)      288.93      (18.24)      270.69
PARKER & PARSLEY 90-A CONV., L.P.                        233.70       30.00           (4.26)      259.44      (18.61)      240.83
PARKER & PARSLEY 90-A, L.P.                              233.70       30.61           (4.26)      260.05      (18.61)      241.44
PARKER & PARSLEY 90-B CONV., L.P.                        264.06       26.06           (4.81)      285.31      (20.34)      264.97
PARKER & PARSLEY 90-B, L.P.                              264.28       26.27           (4.82)      285.73      (20.34)      265.39
PARKER & PARSLEY 90-C CONV., L.P.                        240.17       23.39           (4.38)      259.18      (15.22)      243.96
PARKER & PARSLEY 90-C, L.P.                              240.18       22.68           (4.38)      258.48      (15.22)      243.26
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.             308.08       28.37           (5.61)      330.84      (20.44)      310.40
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.         288.77       27.40           (5.26)      310.91      (22.40)      288.51
PARKER & PARSLEY 91-A, L.P.                              401.35       33.61           (7.31)      427.65      (26.41)      401.24
PARKER & PARSLEY 91-B, L.P.                              439.13       36.88           (8.00)      468.01      (25.28)      442.73




                                      A-4
   106



                                     TABLE 4

              OWNERSHIP PERCENTAGE AND MERGER VALUE ATTRIBUTABLE TO
               NONMANAGING GENERAL PARTNERS OTHER THAN PIONEER USA






                                                                    NONMANAGING GENERAL                       NONMANAGING
                                                                         PARTNERS (a)                  GENERAL PARTNERS' MERGER
                                                            --------------------------------------     VALUE AS A PERCENTAGE OF
                                                               OWNERSHIP               MERGER                MERGER VALUE
                                                             PERCENTAGE (b)           VALUE (c)        FOR THE PARTNERSHIP (d)
                                                            ----------------      ----------------     ------------------------
                                                                                              
PARKER & PARSLEY 81-I, LTD.                                             2.00%     $         16,187                    1.86%
PARKER & PARSLEY 81-II, LTD.                                            1.00%                5,774                    0.93%
PARKER & PARSLEY 82-I, LTD.                                             1.13%               13,293                    1.07%
PARKER & PARSLEY 82-II, LTD.                                            0.84%               12,957                    0.79%
PARKER & PARSLEY 82-III, LTD.                                           0.94%                9,928                    0.90%
PARKER & PARSLEY 83-A, LTD.                                             1.05%               37,001                    1.02%
PARKER & PARSLEY 83-B, LTD.                                             1.05%               48,095                    1.01%
PARKER & PARSLEY 84-A, LTD.                                             1.13%               56,545                    1.09%




----------

(a)      Represents four unaffiliated individuals' partnership interests as
         limited partners of each nonmanaging general partner. Excludes Pioneer
         USA's partnership interests as general partner of each nonmanaging
         general partner.

(b)      Percentage owned is based upon ownership within the partnership as set
         forth in the revenue sharing provisions of the partnership agreement
         for the partnership.

(c)      See "Method of Determining Merger Value for Each Partnership and Amount
         of Pioneer Common Stock and Cash Offered."

(d)      Represents the dollar amount in the nonmanaging general partners'
         merger value column divided by the merger value for the partnership as
         set forth in Table 2.




                                      A-5
   107



                                     TABLE 5

                      OWNERSHIP PERCENTAGE AND MERGER VALUE
                ATTRIBUTABLE TO PIONEER USA IN ITS CAPACITIES AS
        GENERAL PARTNER, NONMANAGING GENERAL PARTNER AND LIMITED PARTNER







                                                                                                               PIONEER USA'S
                                                                                  PIONEER USA (a)            MERGER VALUE AS A
                                                                      ------------------------------------     PERCENTAGE OF
                                                                        OWNERSHIP             MERGER           MERGER VALUE
                                                                      PERCENTAGE (b)          VALUE (c)     FOR THE PARTNERSHIP (d)
                                                                      ---------------      ---------------  ----------------------
                                                                                                   
PARKER & PARSLEY 81-I, LTD.                                                     27.38%     $       225,691               25.92%
PARKER & PARSLEY 81-II, LTD.                                                    24.41%             142,209               23.02%
PARKER & PARSLEY 82-I, LTD.                                                     31.92%             384,588               30.98%
PARKER & PARSLEY 82-II, LTD.                                                    26.92%             417,948               25.64%
PARKER & PARSLEY 82-III, LTD.                                                   28.54%             305,950               27.72%
PARKER & PARSLEY 83-A, LTD.                                                     26.55%             940,944               25.84%
PARKER & PARSLEY 83-B, LTD.                                                     26.76%           1,233,793               25.95%
PARKER & PARSLEY 84-A, LTD.                                                     25.49%           1,285,776               24.86%
PARKER & PARSLEY 85-A, LTD.                                                      2.93%              41,068                2.93%
PARKER & PARSLEY 85-B, LTD.                                                      1.72%              20,207                1.72%
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.                                   3.38%              50,076                3.38%
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.                            2.69%              24,401                2.69%
PARKER & PARSLEY 86-A, LTD.                                                      1.34%              24,320                1.34%
PARKER & PARSLEY 86-B, LTD.                                                      1.74%              67,657                1.74%
PARKER & PARSLEY 86-C, LTD.                                                      1.31%              41,133                1.31%
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                                     1.00%              12,640                1.00%
PARKER & PARSLEY 87-A CONV., LTD.                                                1.90%              14,150                1.90%
PARKER & PARSLEY 87-A, LTD.                                                      1.60%              88,920                1.60%
PARKER & PARSLEY 87-B CONV., LTD.                                                1.20%              12,012                1.20%
PARKER & PARSLEY 87-B, LTD.                                                      1.22%              49,926                1.22%
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.                                 1.35%              35,132                1.35%
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.                                 2.59%              62,154                2.59%
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                                     1.00%              29,502                1.00%
PARKER & PARSLEY 88-A CONV., L.P.                                                2.31%              21,672                2.31%
PARKER & PARSLEY 88-A, L.P.                                                      2.32%              74,684                2.32%
PARKER & PARSLEY 88-B CONV., L.P.                                                1.54%              18,200                1.54%
PARKER & PARSLEY 88-B, L.P.                                                      2.04%              59,211                2.04%
PARKER & PARSLEY 88-C CONV., L.P.                                                1.29%              12,256                1.29%
PARKER & PARSLEY 88-C, L.P.                                                      1.20%               8,093                1.20%
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.                                 1.69%              34,210                1.69%
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                                     1.00%              34,558                1.00%
PARKER & PARSLEY 89-A CONV., L.P.                                                1.00%               9,323                1.00%
PARKER & PARSLEY 89-A, L.P.                                                      2.25%              62,481                2.25%
PARKER & PARSLEY 89-B CONV., L.P.                                                1.31%              23,671                1.31%
PARKER & PARSLEY 89-B, L.P.                                                      2.03%              40,152                2.03%
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                                     1.56%              30,131                1.56%
PARKER & PARSLEY 90-A CONV., L.P.                                                1.59%               9,110                1.59%
PARKER & PARSLEY 90-A, L.P.                                                      3.14%              52,103                3.14%
PARKER & PARSLEY 90-B CONV., L.P.                                                1.67%              53,040                1.67%
PARKER & PARSLEY 90-B, L.P.                                                      1.25%             108,517                1.25%
PARKER & PARSLEY 90-C CONV., L.P.                                                1.39%              25,877                1.39%
PARKER & PARSLEY 90-C, L.P.                                                      1.22%              36,317                1.22%
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                                     1.54%              53,018                1.54%
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.                                 1.00%              15,154                1.00%
PARKER & PARSLEY 91-A, L.P.                                                      1.38%              65,151                1.38%
PARKER & PARSLEY 91-B, L.P.                                                      1.09%              54,733                1.09%




---------------

(a)      Represents Pioneer USA's partnership interests in each partnership as:
         (1) the sole or managing general partner of the partnership; (2) a
         limited partner of the partnership; and (3) the sole general partner of
         each nonmanaging general partner. Pioneer USA will not receive any
         Pioneer common stock or cash payment for its partnership interests in
         any participating partnership. However, as a result of the merger of
         each participating partnership, Pioneer USA will own 100% of the
         properties of the partnership including properties attributable to its
         partnership interests in the partnership.

(b)      Percentage owned is based upon ownership within the partnership as set
         forth in the revenue sharing provisions of the partnership agreement
         for the partnership.

(c)      See "Method of Determining Merger Value for Each Partnership and Amount
         of Pioneer Common Stock and Cash Offered."

(d)      Represents the dollar amount in Pioneer USA's merger value column
         divided by the merger value for the partnership as set forth in Table
         2.




                                      A-6
   108



                                     TABLE 6

          VOTING PERCENTAGE AND INITIAL INVESTMENT OWNED BY PIONEER USA
                      IN ITS CAPACITY AS A LIMITED PARTNER
                              AS OF MARCH 31, 2001





                                                                                         Initial Investment
                                                                       Pioneer Usa            Owned by
                                                                          Voting           Pioneer Usa (d)
                                                                     Percentage (A) (B)    (In Thousands)
                                                                     ------------------  ------------------
                                                                                     
PARKER & PARSLEY 81-I, LTD.                                                      5.84%     $          433
PARKER & PARSLEY 81-II, LTD.                                                     0.55%                 35
PARKER & PARSLEY 82-I, LTD.                                                     10.73%              1,267
PARKER & PARSLEY 82-II, LTD.                                                     3.69%                452
PARKER & PARSLEY 82-III, LTD.                                                    5.97%                411
PARKER & PARSLEY 83-A, LTD.                                                      3.47%                676
PARKER & PARSLEY 83-B, LTD.                                                      3.75%                877
PARKER & PARSLEY 84-A, LTD.                                                      2.16%                419
PARKER & PARSLEY 85-A, LTD. (c)                                                  0.00%                187
PARKER & PARSLEY 85-B, LTD. (c)                                                  0.00%                 58
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD. (c)                               0.00%                120
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD. (c)                        0.00%                 80
PARKER & PARSLEY 86-A, LTD.                                                      0.35%                 35
PARKER & PARSLEY 86-B, LTD.                                                      0.74%                128
PARKER & PARSLEY 86-C, LTD.                                                      0.31%                 60
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD. (c)                                 0.00%                 --
PARKER & PARSLEY 87-A CONV., LTD.                                                0.91%                 35
PARKER & PARSLEY 87-A, LTD.                                                      0.61%                175
PARKER & PARSLEY 87-B CONV., LTD.                                                0.20%                 10
PARKER & PARSLEY 87-B, LTD.                                                      0.22%                 45
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.                                 0.35%                 43
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.                                 1.61%                 98
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                                     0.00%                 --
PARKER & PARSLEY 88-A CONV., L.P.                                                1.32%                 50
PARKER & PARSLEY 88-A, L.P.                                                      1.34%                173
PARKER & PARSLEY 88-B CONV., L.P.                                                0.55%                 20
PARKER & PARSLEY 88-B, L.P.                                                      1.05%                 94
PARKER & PARSLEY 88-C CONV., L.P.                                                0.29%                 10
PARKER & PARSLEY 88-C, L.P.                                                      0.21%                  5
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.                                 0.70%                 39
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                                     0.00%                 --
PARKER & PARSLEY 89-A CONV., L.P.                                                0.00%                 --
PARKER & PARSLEY 89-A, L.P.                                                      1.26%                105
PARKER & PARSLEY 89-B CONV., L.P.                                                0.32%                 20
PARKER & PARSLEY 89-B, L.P.                                                      1.04%                 72
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                                     0.57%                 40
PARKER & PARSLEY 90-A CONV., L.P.                                                0.59%                 14
PARKER & PARSLEY 90-A, L.P.                                                      2.16%                147
PARKER & PARSLEY 90-B CONV., L.P.                                                0.67%                 80
PARKER & PARSLEY 90-B, L.P.                                                      0.26%                 83
PARKER & PARSLEY 90-C CONV., L.P.                                                0.40%                 30
PARKER & PARSLEY 90-C, L.P.                                                      0.22%                 27
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                                     0.55%                 60
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.                                 0.00%                 --
PARKER & PARSLEY 91-A, L.P. (c)                                                  0.00%                 45
PARKER & PARSLEY 91-B, L.P. (c)                                                  0.00%                 10




----------

(a)      Represents Pioneer USA's partnership interests in each partnership as a
         limited partner of the partnership. Pioneer USA will not receive any
         Pioneer common stock or cash payment for its partnership interests in
         any participating partnership. However, as a result of the merger of
         each participating partnership, Pioneer USA will own 100% of the
         properties of the partnership including properties attributable to its
         partnership interests in the partnership.

(b)      Represents percentage of limited partners' vote that Pioneer USA is
         entitled to vote. The voting percentage is calculated by dividing (1)
         Pioneer USA's ownership percentage of the partnership interests held as
         a limited partner, by (2) the percentage of partnership interests held
         by all limited partners in the partnership. For example, if the limited
         partners of a partnership represent 99% of the partnership and Pioneer
         USA owns 5% of the partnership interests as a limited partner in that
         partnership, Pioneer USA's voting percentage is 5.05%.

(c)      Pioneer USA is not entitled to vote partnership interests it holds as
         limited partner in this partnership.

(d)      Represents Pioneer USA's share of the initial investment by limited
         partners as shown on Table 1.




                                      A-7
   109



                                     TABLE 7

     HISTORICAL QUARTERLY PARTNERSHIP DISTRIBUTIONS TO THE LIMITED PARTNERS
                              Per $1,000 Investment
                      From Inception Through July 31, 2001






                                                                              QUARTERLY DISTRIBUTIONS
                                                                                 TO LIMITED PARTNERS
                                                                                PER $1,000 INVESTMENT (a)
                                                          ----------------------------------------------------------------
                                                          Inception  Quarter  Quarter  Quarter   Quarter  Quarter  Quarter
                                                              To      ended    ended    ended    ended     ended    ended
                                                          12/31/98   3/31/99  6/30/99  9/30/99  12/31/99  3/31/00  6/30/00
                                                          ---------  -------  -------  -------  --------  -------  -------
                                                                                              
PARKER & PARSLEY 81-I, LTD.                               $  616.71   $ 0.69   $   --   $ 3.26   $ 2.42   $ 4.24   $ 5.53
PARKER & PARSLEY 81-II, LTD.                                 808.37       --     0.35     1.26     2.71     2.01     2.99
PARKER & PARSLEY 82-I, LTD.                                  946.73     0.62     0.53     2.03     1.09     3.93     4.77
PARKER & PARSLEY 82-II, LTD.                               1,099.24     0.83       --     3.34     3.48     4.98     6.07
PARKER & PARSLEY 82-III, LTD.                                924.16       --     1.69     2.92     5.07     7.49     7.80
PARKER & PARSLEY 83-A, LTD.                                1,264.54       --       --     4.11     5.20     7.22     7.30
PARKER & PARSLEY 83-B, LTD.                                1,458.60     0.96     1.79     4.89     6.30     8.70     9.68
PARKER & PARSLEY 84-A, LTD.                                1,384.63     0.80     2.78     4.69     6.81     8.28    11.17
PARKER & PARSLEY 85-A, LTD.                                  678.73     0.83     1.49     4.98     9.55     7.09    11.26
PARKER & PARSLEY 85-B, LTD.                                  876.32       --     3.17     4.12     7.19     7.95     9.04
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.               997.86     3.16     5.23     8.79    12.34    15.51    20.44
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.        872.24     1.66       --     4.33     6.68     9.18    11.68
PARKER & PARSLEY 86-A, LTD.                                1,279.93     0.79     2.23     6.38     5.82     8.66    11.38
PARKER & PARSLEY 86-B, LTD.                                1,469.69     1.53     5.01     5.85     8.40    10.40    13.08
PARKER & PARSLEY 86-C, LTD.                                1,401.81     0.82     2.38     1.77     7.30     8.35     9.67
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.               1,525.50     1.23     1.22     5.88     5.44    14.07     9.36
PARKER & PARSLEY 87-A CONV., LTD.                          1,228.63     1.83     2.20     6.07     7.90    11.58    15.18
PARKER & PARSLEY 87-A, LTD.                                1,228.70     1.83     2.20     6.07     7.90    11.58    15.18
PARKER & PARSLEY 87-B CONV., LTD.                          1,154.18     1.85     2.29     5.50     8.64    10.07    12.58
PARKER & PARSLEY 87-B, LTD.                                1,154.25     1.85     2.29     5.50     8.64    10.07    12.58
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.             889.65     1.49     0.89     6.21     9.75    10.92    13.50
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.             956.04     3.97     1.02     8.98    13.99    18.53    24.65
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.               1,457.32     2.20     4.09     8.56     9.55    12.55    13.19
PARKER & PARSLEY 88-A CONV., L.P.                            991.51     3.16     3.06     7.97    11.11    12.48    15.67
PARKER & PARSLEY 88-A, L.P.                                  991.61     3.16     3.06     7.97    11.11    12.48    15.67
PARKER & PARSLEY 88-B CONV., L.P.                            966.33     3.44     2.88     8.95    13.65    18.22    20.69
PARKER & PARSLEY 88-B, L.P.                                  966.37     3.44     2.88     8.95    13.65    18.22    20.69
PARKER & PARSLEY 88-C CONV., L.P.                            913.42     3.92     2.34     4.27    11.12    16.38    18.34
PARKER & PARSLEY 88-C, L.P.                                  913.01     3.92     2.34     4.27    11.12    16.38    18.34
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.           1,075.69     6.51     4.02     7.58    11.34    21.95    19.09
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.               1,031.07     3.57     6.66     8.39    12.47    15.99    19.23
PARKER & PARSLEY 89-A CONV., L.P.                            911.13     2.66     2.77     9.16    13.97    17.96    18.39
PARKER & PARSLEY 89-A, L.P.                                  911.19     2.66     2.77     9.16    13.97    17.96    18.39
PARKER & PARSLEY 89-B CONV., L.P.                            787.19     3.26     1.22     8.31    11.43    14.28    18.94
PARKER & PARSLEY 89-B, L.P.                                  787.20     3.26     1.22     8.31    11.43    14.28    18.94
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                 689.19     1.02     1.85     6.67     4.97    13.32    15.00
PARKER & PARSLEY 90-A CONV., L.P.                            784.83     3.18     1.68     8.12     9.46    12.70    14.52
PARKER & PARSLEY 90-A, L.P.                                  784.89     3.18     1.68     8.12     9.46    12.70    14.52
PARKER & PARSLEY 90-B CONV., L.P.                            600.45     2.10     1.80     7.47    11.46    14.98    15.20
PARKER & PARSLEY 90-B, L.P.                                  600.53     2.10     1.80     7.47    11.46    14.98    15.20
PARKER & PARSLEY 90-C CONV., L.P.                            537.51     0.95       --     6.26    10.83    13.62    14.90
PARKER & PARSLEY 90-C, L.P.                                  537.52     0.95       --     6.26    10.83    13.62    14.90
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                 673.63     2.14     3.11     5.62    12.23    15.05    18.11
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.             632.08     3.71     3.09     6.40    13.59    16.68    13.98
PARKER & PARSLEY 91-A, L.P.                                  663.47     3.99     6.33    11.37    15.54    20.76    23.19
PARKER & PARSLEY 91-B, L.P.                                  526.98     3.95     7.05    13.55    18.24    21.87    26.88


                                                                              QUARTERLY DISTRIBUTIONS
                                                                                 TO LIMITED PARTNERS
                                                                                PER $1,000 INVESTMENT (a)
                                                       ---------------------------------------------------------------------------
                                                        Quarter      Quarter      Quarter      Quarter       Month      Inception
                                                         ended        ended         ended       ended        ended         To
                                                        9/30/00      12/31/00      3/31/01      6/30/01     7/31/01      7/31/01
                                                       ----------   ----------   ----------   ----------   ----------   ----------
                                                                                                      
PARKER & PARSLEY 81-I, LTD.                            $     4.53   $     5.41   $     6.91   $       --   $     7.43   $   657.13
PARKER & PARSLEY 81-II, LTD.                                 5.00         5.97         6.88           --         6.33       841.87
PARKER & PARSLEY 82-I, LTD.                                  6.70         4.06         8.08           --         7.39       985.93
PARKER & PARSLEY 82-II, LTD.                                 4.58         6.41         8.01           --         5.04     1,141.98
PARKER & PARSLEY 82-III, LTD.                                9.38         8.84        10.27           --         7.72       985.34
PARKER & PARSLEY 83-A, LTD.                                  9.04        10.25        12.04           --         8.56     1,328.26
PARKER & PARSLEY 83-B, LTD.                                 11.28        10.66        11.10           --         8.20     1,532.16
PARKER & PARSLEY 84-A, LTD.                                 12.41        13.00        14.37           --        12.51     1,471.45
PARKER & PARSLEY 85-A, LTD.                                  9.94        10.41        13.70           --         9.33       757.31
PARKER & PARSLEY 85-B, LTD.                                  9.26        12.47        15.53           --         9.76       954.81
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.              16.65        16.32        18.72           --        16.62     1,131.64
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.       12.92        12.98        18.63           --        16.85       967.15
PARKER & PARSLEY 86-A, LTD.                                 12.54        13.08        18.73           --         1.08     1,360.62
PARKER & PARSLEY 86-B, LTD.                                 14.24        15.95        18.32           --        13.25     1,575.72
PARKER & PARSLEY 86-C, LTD.                                 12.04        12.45        15.95           --        14.38     1,486.92
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                17.03        15.11        22.67           --        16.82     1,634.33
PARKER & PARSLEY 87-A CONV., LTD.                           13.96        12.79        16.86           --        15.03     1,332.03
PARKER & PARSLEY 87-A, LTD.                                 13.96        12.79        16.86           --        15.03     1,332.10
PARKER & PARSLEY 87-B CONV., LTD.                           13.53        12.84        17.13           --        12.85     1,251.46
PARKER & PARSLEY 87-B, LTD.                                 13.53        12.84        17.13           --        12.85     1,251.53
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.            12.12        14.11        21.51           --        20.23     1,000.38
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.            26.75        26.21        27.53           --        19.38     1,127.05
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                14.14        16.03        18.36           --        19.75     1,575.74
PARKER & PARSLEY 88-A CONV., L.P.                           17.33        16.95        20.80           --        20.40     1,120.44
PARKER & PARSLEY 88-A, L.P.                                 17.33        16.95        20.80           --        20.40     1,120.54
PARKER & PARSLEY 88-B CONV., L.P.                           22.63        25.37        28.91           --        18.63     1,129.70
PARKER & PARSLEY 88-B, L.P.                                 22.63        25.37        28.91           --        18.63     1,129.74
PARKER & PARSLEY 88-C CONV., L.P.                           19.83        21.01        24.91           --        17.26     1,052.80
PARKER & PARSLEY 88-C, L.P.                                 19.83        21.01        24.91           --        17.26     1,052.39
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.            18.82        21.76        27.21           --        20.76     1,234.73
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                23.09        21.51        23.55           --        20.42     1,185.95
PARKER & PARSLEY 89-A CONV., L.P.                           20.40        23.38        29.49           --        20.93     1,070.24
PARKER & PARSLEY 89-A, L.P.                                 20.40        23.38        29.49           --        20.93     1,070.30
PARKER & PARSLEY 89-B CONV., L.P.                           20.23        20.99        26.50           --        19.07       931.42
PARKER & PARSLEY 89-B, L.P.                                 20.23        20.99        26.50           --        19.07       931.43
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                16.66        20.33        13.22           --        18.24       800.47
PARKER & PARSLEY 90-A CONV., L.P.                           17.43        19.18        19.99           --        18.61       909.70
PARKER & PARSLEY 90-A, L.P.                                 17.43        19.18        19.99           --        18.61       909.76
PARKER & PARSLEY 90-B CONV., L.P.                           19.51        19.68        23.73           --        20.34       736.72
PARKER & PARSLEY 90-B, L.P.                                 19.51        19.68        23.73           --        20.34       736.80
PARKER & PARSLEY 90-C CONV., L.P.                           19.01        17.84        21.19           --        15.22       657.33
PARKER & PARSLEY 90-C, L.P.                                 19.01        17.84        21.18           --        15.22       657.33
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                20.29        25.10        27.49           --        20.44       823.21
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.            14.00        13.98        20.44           --        22.40       760.35
PARKER & PARSLEY 91-A, L.P.                                 26.03        30.05        27.29           --        26.41       854.43
PARKER & PARSLEY 91-B, L.P.                                 33.92        35.07        24.81           --        25.28       737.60




----------


(a) Past cash distributions to limited partners are not necessarily indicative
of future cash distributions. Limited partners should not assume that any
nonparticipating partnership will continue to make cash distributions at levels
similar to those shown. See "The Merger of Each Partnership - Distribution of
Pioneer Common Stock and Cash Payment."



                                      A-8
   110


                                     TABLE 8
        ANNUAL REPURCHASE PRICES AND AGGREGATE ANNUAL REPURCHASE PAYMENTS






                                                2001                     2000                      1999
                                      -----------------------   -----------------------   -----------------------
                                      REPURCHASE    AGGREGATE    REPURCHASE   AGGREGATE   REPURCHASE   AGGREGATE
                                        PRICE        ANNUAL       PRICE        ANNUAL       PRICE        ANNUAL
                                      PER $1,000   REPURCHASE   PER $1,000   REPURCHASE   PER $1,000   REPURCHASE
                                      INVESTMENT    PAYMENTS    INVESTMENT    PAYMENTS    INVESTMENT    PAYMENTS
                                      ----------   ----------   ----------   ----------   ----------   ----------
                                                                                     
PARKER & PARSLEY 82-I, LTD.           $   137.97          (a)   $    71.89   $    4,745   $     7.52   $       94
PARKER & PARSLEY 82-II, LTD.              133.72          (a)       102.38        1,024        26.17          131
PARKER & PARSLEY 82-III, LTD.             150.59          (a)       109.73        1,097        12.17          284
PARKER & PARSLEY 83-A, LTD.               196.67          (a)       137.59        9,494        27.05          541
PARKER & PARSLEY 83-B, LTD.               210.15          (a)       153.89        3,078        43.46           --
PARKER & PARSLEY 84-A, LTD.               267.03          (a)       175.78        7,031        45.72        1,143
                                                                                          ----------   ----------
                                                                                          $   26,469   $    2,193
                                                                                          ==========   ==========




----------

(a)      Payments will not be made until the third quarter of 2001.



                                      A-9
   111


                                     TABLE 9

                       PARTICIPATION IN COSTS AND REVENUES
                               OF EACH PARTNERSHIP





                                                             CAPITAL COSTS                         REVENUES AND EXPENSES
                                                ---------------------------------------  --------------------------------------
                                                                            NONMANAGING                  NONMANAGING
                                                 GENERAL        GENERAL        LIMITED       GENERAL       GENERAL      LIMITED
                                                PARTNER (a)   PARTNERS (a)   PARTNERS (a)   PARTNER (a)  PARTNERS (a) PARTNERS (a)
                                                ----------   -------------  ------------  -------------  ------------ ------------
                                                                                                    
PARKER & PARSLEY 81-I, LTD.                              8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 81-II, LTD.                             8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 82-I, LTD.                              8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 82-II, LTD.                             8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 82-III, LTD.                            8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 83-A, LTD. (b)                          8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 83-B, LTD. (b)                          8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 84-A, LTD. (b)                          8%              2%          90%            20%           5%          75%
PARKER & PARSLEY 85-A, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 85-B, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.           1%             --           99%             1%          --           99%
PARKER & PARSLEY SELECTED 85 PRIVATE
  INVESTMENT, LTD.                                       1%             --           99%             1%          --           99%
PARKER & PARSLEY 86-A, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 86-B, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 86-C, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.             1%             --           99%             1%          --           99%
PARKER & PARSLEY 87-A CONV., LTD.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 87-A, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 87-B CONV., LTD.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 87-B, LTD.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.         1%             --           99%             1%          --           99%
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.         1%             --           99%             1%          --           99%
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.             1%             --           99%             1%          --           99%
PARKER & PARSLEY 88-A CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 88-A, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 88-B CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 88-B, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 88-C CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 88-C, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.         1%             --           99%             1%          --           99%
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.             1%             --           99%             1%          --           99%
PARKER & PARSLEY 89-A CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 89-A, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 89-B CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 89-B, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.             1%             --           99%             1%          --           99%
PARKER & PARSLEY 90-A CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 90-A, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 90-B CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 90-B, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 90-C CONV., L.P.                        1%             --           99%             1%          --           99%
PARKER & PARSLEY 90-C, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.             1%             --           99%             1%          --           99%
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.         1%             --           99%             1%          --           99%
PARKER & PARSLEY 91-A, L.P.                              1%             --           99%             1%          --           99%
PARKER & PARSLEY 91-B, L.P.                              1%             --           99%             1%          --           99%




----------

(a)      These percentages represent the sharing ownerships as set forth in the
         prospectus for each partnership. Includes Pioneer USA's partnership
         interests in each partnership as: (1) the sole or managing general
         partner of the partnership; (2) a limited partner of the partnership;
         and (3) the sole general partner of each nonmanaging general partner.
         Pioneer USA will not receive any Pioneer common stock or cash payment
         for its partnership interests in any participating partnership.

(b)      Incremental direct costs 100% to limited partners.



                                      A-10
   112


                                    TABLE 10

   AVERAGE OIL, NATURAL GAS LIQUIDS AND GAS SALES PRICES AND PRODUCTION COSTS
                  FOR THE THREE MONTHS ENDED MARCH 31, 2001 AND
           2000 AND THE YEARS ENDED DECEMBER 31, 2000, 1999 AND 1998





                                                                              AVERAGE SALES PRICE
                                                        --------------------------------------------------------------
                                                                                 OIL (PER BBL)
                                                        --------------------------------------------------------------
                                                         FOR THE THREE MONTHS              FOR THE YEAR ENDED
                                                             ENDED MARCH 31,                   DECEMBER 31,
                                                           2001         2000         2000         1999         1998
                                                        ----------   ----------   ----------   ----------   ----------
                                                                                             
PARKER & PARSLEY 81-I, LTD.                             $    28.55   $    27.16   $    29.26   $    16.94   $    13.33
PARKER & PARSLEY 81-II, LTD.                                 27.86        27.34        29.26        16.67        13.16
PARKER & PARSLEY 82-I, LTD.                                  28.02        27.23        29.39        16.61        13.32
PARKER & PARSLEY 82-II, LTD.                                 28.12        27.27        29.47        17.08        13.14
PARKER & PARSLEY 82-III, LTD.                                28.58        27.64        29.67        17.13        13.31
PARKER & PARSLEY 83-A, LTD.                                  28.05        27.44        29.54        16.96        13.34
PARKER & PARSLEY 83-B, LTD.                                  28.39        27.66        29.69        17.18        13.30
PARKER & PARSLEY 84-A, LTD.                                  27.16        27.61        29.55        17.36        13.30
PARKER & PARSLEY 85-A, LTD.                                  28.29        27.40        29.38        17.11        13.27
PARKER & PARSLEY 85-B, LTD.                                  28.85        28.65        30.02        18.07        13.30
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.               28.73        27.36        30.19        16.91        13.20
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.        28.33        27.34        29.59        17.27        13.44
PARKER & PARSLEY 86-A, LTD.                                  28.20        27.46        28.87        17.00        13.32
PARKER & PARSLEY 86-B, LTD.                                  28.95        27.60        29.45        17.18        13.08
PARKER & PARSLEY 86-C, LTD.                                  27.96        27.56        29.43        17.18        13.26
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                 28.55        27.55        29.45        17.34        13.34
PARKER & PARSLEY 87-A CONV., LTD.                            27.84        27.18        29.46        17.06        13.22
PARKER & PARSLEY 87-A, LTD.                                  27.84        27.18        29.46        17.06        13.22
PARKER & PARSLEY 87-B CONV., LTD.                            27.55        27.69        29.31        16.71        13.17
PARKER & PARSLEY 87-B, LTD.                                  27.55        27.69        29.31        16.71        13.17
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.             27.48        27.47        29.34        16.80        13.04
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.             27.14        27.54        29.36        17.44        13.05
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                 27.13        27.10        29.56        16.82        13.05
PARKER & PARSLEY 88-A CONV., L.P.                            25.98        27.90        29.28        16.91        13.59
PARKER & PARSLEY 88-A, L.P.                                  25.98        27.90        29.28        16.91        13.59
PARKER & PARSLEY 88-B CONV., L.P.                            29.80        26.41        29.29        17.17        13.24
PARKER & PARSLEY 88-B, L.P.                                  29.80        26.41        29.29        17.17        13.24
PARKER & PARSLEY 88-C CONV., L.P.                            30.11        26.37        29.33        17.24        13.30
PARKER & PARSLEY 88-C, L.P.                                  30.11        26.37        29.33        17.24        13.30
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.             27.40        27.98        29.44        16.82        13.14
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                 27.93        27.22        29.45        17.01        13.31
PARKER & PARSLEY 89-A CONV., L.P.                            28.10        27.48        29.59        17.11        13.23
PARKER & PARSLEY 89-A, L.P.                                  28.10        27.48        29.59        17.11        13.23
PARKER & PARSLEY 89-B CONV., L.P.                            28.41        27.13        29.21        16.96        13.26
PARKER & PARSLEY 89-B, L.P.                                  28.41        27.13        29.21        16.96        13.26
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                 27.47        26.78        29.00        17.06        13.28
PARKER & PARSLEY 90-A CONV., L.P.                            28.38        27.38        29.32        17.06        13.20
PARKER & PARSLEY 90-A, L.P.                                  28.38        27.38        29.32        17.06        13.20
PARKER & PARSLEY 90-B CONV., L.P.                            29.26        27.70        29.23        17.23        13.12
PARKER & PARSLEY 90-B, L.P.                                  29.26        27.70        29.23        17.23        13.12
PARKER & PARSLEY 90-C CONV., L.P.                            28.08        27.16        29.34        17.13        13.24
PARKER & PARSLEY 90-C, L.P.                                  28.08        27.16        29.34        17.13        13.24
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                 28.27        27.27        29.35        17.30        13.19
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.             27.96        26.99        29.17        17.04        13.06
PARKER & PARSLEY 91-A, L.P.                                  27.99        27.88        29.90        17.57        13.15
PARKER & PARSLEY 91-B, L.P.                                  28.83        28.53        30.09        17.90        13.33



                                                                              AVERAGE SALES PRICE
                                                        --------------------------------------------------------------
                                                                                  NGL (PER BBL)
                                                         -------------------------------------------------------------
                                                           FOR THE THREE MONTHS              FOR THE YEAR ENDED
                                                              ENDED MARCH 31,                   DECEMBER 31,
                                                            2001         2000         2000         1999        1998
                                                         ----------   ----------   ----------   ----------   ----------
                                                                                              
PARKER & PARSLEY 81-I, LTD.                              $    16.71   $    14.58   $    14.60   $     9.22   $     6.40
PARKER & PARSLEY 81-II, LTD.                                  20.90        17.54        15.59         8.70         6.73
PARKER & PARSLEY 82-I, LTD.                                   19.68        12.67        14.44         8.96         7.20
PARKER & PARSLEY 82-II, LTD.                                  19.54        13.18        15.01         9.80         6.93
PARKER & PARSLEY 82-III, LTD.                                 16.89        12.20        13.86         9.13         6.42
PARKER & PARSLEY 83-A, LTD.                                   19.07        14.18        15.58         9.42         6.49
PARKER & PARSLEY 83-B, LTD.                                   18.66        13.48        15.47        10.00         6.79
PARKER & PARSLEY 84-A, LTD.                                   16.20        12.70        14.00         9.03         6.08
PARKER & PARSLEY 85-A, LTD.                                   17.68        12.16        14.20         9.71         6.51
PARKER & PARSLEY 85-B, LTD.                                   18.94        14.41        15.96        10.10         6.95
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.                17.26        13.27        15.22         9.95         6.49
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.         18.19        13.50        15.52        10.49         6.99
PARKER & PARSLEY 86-A, LTD.                                   18.84        13.90        14.94         9.63         6.53
PARKER & PARSLEY 86-B, LTD.                                   19.15        13.37        15.00         9.39         6.80
PARKER & PARSLEY 86-C, LTD.                                   18.08        13.64        15.06         9.27         6.46
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                  18.32        13.33        15.01         9.27         6.69
PARKER & PARSLEY 87-A CONV., LTD.                             18.62        15.12        16.01         9.81         6.76
PARKER & PARSLEY 87-A, LTD.                                   18.62        15.12        16.01         9.81         6.76
PARKER & PARSLEY 87-B CONV., LTD.                             18.92        15.18        16.90         9.73         6.82
PARKER & PARSLEY 87-B, LTD.                                   18.92        15.18        16.90         9.73         6.82
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.              13.37        11.93        12.12         7.32         5.46
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.              19.07        14.93        16.68        10.32         6.58
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                  19.52        14.77        16.17         9.41         6.55
PARKER & PARSLEY 88-A CONV., L.P.                             18.12        13.93        15.30         9.30         6.57
PARKER & PARSLEY 88-A, L.P.                                   18.12        13.93        15.30         9.30         6.57
PARKER & PARSLEY 88-B CONV., L.P.                             19.97        14.34        16.02        10.03         6.91
PARKER & PARSLEY 88-B, L.P.                                   19.97        14.34        16.02        10.03         6.91
PARKER & PARSLEY 88-C CONV., L.P.                             19.45        14.26        15.83        10.42         6.94
PARKER & PARSLEY 88-C, L.P.                                   19.45        14.26        15.83        10.42         6.94
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.              16.07        13.03        14.28         9.18         6.31
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                  18.85        14.02        15.61         9.32         6.79
PARKER & PARSLEY 89-A CONV., L.P.                             17.36        13.84        15.42         9.54         6.95
PARKER & PARSLEY 89-A, L.P.                                   17.36        13.84        15.42         9.54         6.95
PARKER & PARSLEY 89-B CONV., L.P.                             19.38        14.82        15.56         9.57         6.94
PARKER & PARSLEY 89-B, L.P.                                   19.38        14.82        15.56         9.57         6.94
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                  16.74        11.59        14.86         8.69         6.57
PARKER & PARSLEY 90-A CONV., L.P.                             19.39        13.78        15.62         9.58         7.02
PARKER & PARSLEY 90-A, L.P.                                   19.39        13.78        15.62         9.58         7.02
PARKER & PARSLEY 90-B CONV., L.P.                             18.25        13.89        15.45         9.49         6.60
PARKER & PARSLEY 90-B, L.P.                                   18.25        13.89        15.45         9.49         6.60
PARKER & PARSLEY 90-C CONV., L.P.                             18.95        12.95        14.91         9.31         6.80
PARKER & PARSLEY 90-C, L.P.                                   18.95        12.95        14.91         9.31         6.80
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                  19.81        14.06        15.82         9.46         6.77
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.              19.29        14.49        15.56         9.70         6.89
PARKER & PARSLEY 91-A, L.P.                                   14.86        13.65        14.94         9.34         6.44
PARKER & PARSLEY 91-B, L.P.                                   18.47        15.13        16.50        10.15         6.79






                                                                           AVERAGE SALES PRICE
                                                     -------------------------------------------------------------
                                                                              GAS (PER MCF)
                                                     -------------------------------------------------------------
                                                     FOR THE THREE MONTHS            FOR THE YEAR ENDED
                                                        ENDED MARCH 31,                  DECEMBER 31,
                                                       2001         2000          2000       1999          1998
                                                     ---------   ----------   ----------   ----------   ----------
                                                                                         
PARKER & PARSLEY 81-I, LTD.                               6.07   $     1.83   $     3.22   $     1.78   $     1.78
PARKER & PARSLEY 81-II, LTD.                              6.36         1.26         3.07         1.82         1.80
PARKER & PARSLEY 82-I, LTD.                               5.65         2.33         3.29         1.95         1.82
PARKER & PARSLEY 82-II, LTD.                              5.65         1.90         2.98         1.79         1.64
PARKER & PARSLEY 82-III, LTD.                             5.49         1.60         2.54         1.65         1.53
PARKER & PARSLEY 83-A, LTD.                               5.93         1.76         3.02         1.78         1.60
PARKER & PARSLEY 83-B, LTD.                               5.74         1.76         2.83         1.66         1.54
PARKER & PARSLEY 84-A, LTD.                               4.80         1.54         2.49         1.47         1.33
PARKER & PARSLEY 85-A, LTD.                               5.42         1.71         2.66         1.70         1.56
PARKER & PARSLEY 85-B, LTD.                               5.77         1.84         2.92         1.72         1.58
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.            5.42         1.58         2.65         1.54         1.41
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.     5.37         1.70         2.77         1.67         1.56
PARKER & PARSLEY 86-A, LTD.                               5.76         1.63         2.56         1.57         1.46
PARKER & PARSLEY 86-B, LTD.                               6.27         1.76         2.82         1.71         1.58
PARKER & PARSLEY 86-C, LTD.                               5.59         1.62         2.78         1.58         1.49
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.              5.70         1.81         2.90         1.73         1.61
PARKER & PARSLEY 87-A CONV., LTD.                         5.51         1.75         2.86         1.68         1.54
PARKER & PARSLEY 87-A, LTD.                               5.51         1.75         2.86         1.68         1.54
PARKER & PARSLEY 87-B CONV., LTD.                         6.24         1.75         2.98         1.64         1.49
PARKER & PARSLEY 87-B, LTD.                               6.24         1.75         2.98         1.64         1.49
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.          4.69         1.84         2.56         1.46         1.23
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.          5.93         1.78         2.88         1.62         1.46
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.              6.07         1.86         2.99         1.71         1.59
PARKER & PARSLEY 88-A CONV., L.P.                         4.62         1.73         2.99         1.69         1.56
PARKER & PARSLEY 88-A, L.P.                               4.62         1.73         2.99         1.69         1.56
PARKER & PARSLEY 88-B CONV., L.P.                         9.14         1.73         2.87         1.70         1.56
PARKER & PARSLEY 88-B, L.P.                               9.14         1.73         2.87         1.70         1.56
PARKER & PARSLEY 88-C CONV., L.P.                         8.12         1.70         2.82         1.70         1.55
PARKER & PARSLEY 88-C, L.P.                               8.12         1.70         2.82         1.70         1.55
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.          5.11         1.53         2.55         1.48         1.41
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.              6.05         1.75         2.82         1.69         1.55
PARKER & PARSLEY 89-A CONV., L.P.                         6.16         1.91         3.07         1.81         1.74
PARKER & PARSLEY 89-A, L.P.                               6.16         1.91         3.07         1.81         1.74
PARKER & PARSLEY 89-B CONV., L.P.                         5.95         1.79         2.90         1.72         1.60
PARKER & PARSLEY 89-B, L.P.                               5.95         1.79         2.90         1.72         1.60
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.              5.45         1.56         2.73         1.57         1.46
PARKER & PARSLEY 90-A CONV., L.P.                         6.12         1.82         2.94         1.76         1.64
PARKER & PARSLEY 90-A, L.P.                               6.12         1.82         2.94         1.76         1.64
PARKER & PARSLEY 90-B CONV., L.P.                         5.76         1.68         2.84         1.62         1.50
PARKER & PARSLEY 90-B, L.P.                               5.76         1.68         2.84         1.62         1.50
PARKER & PARSLEY 90-C CONV., L.P.                         6.33         1.71         2.89         1.70         1.55
PARKER & PARSLEY 90-C, L.P.                               6.33         1.71         2.89         1.70         1.55
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.              6.09         1.77         2.90         1.72         1.57
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.          5.91         1.68         2.91         1.65         1.60
PARKER & PARSLEY 91-A, L.P.                               6.25         1.81         3.06         1.70         1.56
PARKER & PARSLEY 91-B, L.P.                               6.43         1.73         2.93         1.61         1.47




                                                                   AVERAGE PRODUCTION COSTS (LIFTING)
                                                     -------------------------------------------------------------
                                                                       COST PER EQUIVALENT BBL (a)
                                                     -------------------------------------------------------------
                                                      FOR THE THREE MONTHS            FOR THE YEAR ENDED
                                                        ENDED MARCH 31,                   DECEMBER 31,
                                                       2001         2000         2000         1999          1998
                                                     ---------   ----------   ----------   ----------   ----------
                                                                                         
PARKER & PARSLEY 81-I, LTD.                              11.67   $     8.77   $     9.52   $     8.39   $     8.74
PARKER & PARSLEY 81-II, LTD.                             13.89        16.26        11.46         8.57         8.80
PARKER & PARSLEY 82-I, LTD.                              13.01        10.27        11.91         9.80         9.88
PARKER & PARSLEY 82-II, LTD.                             13.90         9.34        10.25         8.09         7.88
PARKER & PARSLEY 82-III, LTD.                            12.40         7.80         9.20         8.06         9.00
PARKER & PARSLEY 83-A, LTD.                              12.81        10.68        10.52         8.64         8.76
PARKER & PARSLEY 83-B, LTD.                              13.44         8.42         9.12         7.60         8.27
PARKER & PARSLEY 84-A, LTD.                               9.71         7.95         8.64         7.70         7.66
PARKER & PARSLEY 85-A, LTD.                              10.51         9.78         9.66         7.02         8.70
PARKER & PARSLEY 85-B, LTD.                               9.58         9.21        10.19         7.70         8.48
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.            8.44         7.02         7.78         6.40         6.96
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.    10.42         8.91         9.43         8.01         7.82
PARKER & PARSLEY 86-A, LTD.                              12.39         8.67         8.86         7.83         9.36
PARKER & PARSLEY 86-B, LTD.                              11.17         8.77         8.87         7.89         7.64
PARKER & PARSLEY 86-C, LTD.                              10.92        10.72        10.31         8.66         7.67
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.             11.57        10.78        10.84         9.08         7.67
PARKER & PARSLEY 87-A CONV., LTD.                         9.79         8.31         9.11         7.19         7.78
PARKER & PARSLEY 87-A, LTD.                               9.79         8.31         9.11         7.19         7.78
PARKER & PARSLEY 87-B CONV., LTD.                        11.92         7.45         8.63         7.44         6.65
PARKER & PARSLEY 87-B, LTD.                              11.92         7.45         8.63         7.44         6.65
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.         11.49        10.34        12.48         8.97         9.26
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.          9.97         8.79         8.42         8.30         7.84
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.             10.31         9.30         9.13         6.77         6.81
PARKER & PARSLEY 88-A CONV., L.P.                         8.33        10.22         8.85         5.98         7.06
PARKER & PARSLEY 88-A, L.P.                               8.33        10.22         8.85         5.98         7.06
PARKER & PARSLEY 88-B CONV., L.P.                         9.94         6.52         7.84         7.04         7.51
PARKER & PARSLEY 88-B, L.P.                               9.94         6.52         7.84         7.04         7.51
PARKER & PARSLEY 88-C CONV., L.P.                         9.68         7.37         8.10         7.43         7.84
PARKER & PARSLEY 88-C, L.P.                               9.68         7.37         8.10         7.43         7.84
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.          8.45         9.70         9.69         6.31         5.87
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.             10.03         8.20         7.57         6.04         6.60
PARKER & PARSLEY 89-A CONV., L.P.                         8.42         7.97         8.23         6.75         6.92
PARKER & PARSLEY 89-A, L.P.                               8.42         7.97         8.23         6.75         6.92
PARKER & PARSLEY 89-B CONV., L.P.                         9.95         8.45         8.59         7.58         7.30
PARKER & PARSLEY 89-B, L.P.                               9.95         8.45         8.59         7.58         7.30
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.             15.47         8.91         8.99         8.69         6.80
PARKER & PARSLEY 90-A CONV., L.P.                         9.33         7.92         9.43         7.38         6.93
PARKER & PARSLEY 90-A, L.P.                               9.33         7.92         9.43         7.38         6.93
PARKER & PARSLEY 90-B CONV., L.P.                         9.44         8.57         8.68         7.28         7.31
PARKER & PARSLEY 90-B, L.P.                               9.44         8.57         8.68         7.28         7.31
PARKER & PARSLEY 90-C CONV., L.P.                        11.92         9.49         8.83         7.93         8.22
PARKER & PARSLEY 90-C, L.P.                              11.92         9.49         8.83         7.93         8.22
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.              8.66         7.39         8.22         7.01         8.24
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.          8.20         9.35         8.97         7.41         7.44
PARKER & PARSLEY 91-A, L.P.                               9.87         7.38         7.38         6.31         6.04
PARKER & PARSLEY 91-B, L.P.                               9.33         7.18         6.88         5.72         5.96




---------------

(a) Gas production is converted to oil equivalents at the rate of six mcf per
barrel, representing the relative energy content of natural gas and oil.



                                      A-11
   113


                                    TABLE 11

                  PROVED RESERVES ATTRIBUTABLE TO PIONEER USA,
                NONMANAGING GENERAL PARTNERS AND LIMITED PARTNERS
                             AS OF DECEMBER 31, 2000






                                                                      TOTAL PROVED RESERVES
                                   ----------------------------------------------------------------------------------------------
                                                               NONMANAGING
                                        PIONEER USA (a)     GENERAL PARTNERS (b)     LIMITED PARTNERS (c)        TOTAL (D)
                                   ----------------------  ----------------------  ----------------------  ----------------------
                                      OIL &                  OIL &                   OIL &                   OIL &
                                   NGL (BBLS)   GAS (MCF)  NGL (BBLS)  GAS (MCF)   NGL (BBLS)  GAS (MCF)   NGL (BBLS)  GAS (MCF)
                                   ----------  ----------  ----------  ----------  ----------  ----------  ----------  ----------
                                                                                               
PARKER & PARSLEY 81-I, LTD.            57,816     116,841       4,224       8,535     149,140     301,399     211,180     426,775
PARKER & PARSLEY 81-II, LTD.           49,524      72,494       2,029       2,970     151,342     221,535     202,895     296,999
PARKER & PARSLEY 82-I, LTD.           114,245     257,041       4,026       9,058     239,586     539,046     357,857     805,145
PARKER & PARSLEY 82-II, LTD.          109,901     167,908       3,444       5,262     294,856     450,483     408,201     623,653
PARKER & PARSLEY 82-III, LTD.          88,780      85,126       2,916       2,796     219,396     210,367     311,092     298,289
PARKER & PARSLEY 83-A, LTD.           275,918     409,246      10,912      16,185     752,434   1,116,022   1,039,264   1,541,453
PARKER & PARSLEY 83-B, LTD.           340,686     554,365      13,365      21,748     918,850   1,495,154   1,272,901   2,071,267
PARKER & PARSLEY 84-A, LTD.           344,084     570,471      15,185      25,176     990,507   1,642,204   1,349,776   2,237,851
PARKER & PARSLEY 85-A, LTD.            11,187      15,154          --          --     371,156     502,769     382,343     517,923
PARKER & PARSLEY 85-B, LTD.             5,233       7,901          --          --     299,222     451,758     304,455     459,659
PARKER & PARSLEY PRIVATE
  INVESTMENT 85-A, LTD.                11,095      12,053          --          --     317,553     344,957     328,648     357,010
PARKER & PARSLEY SELECTED 85
  PRIVATE INVESTMENT                    6,238      10,351          --          --     225,761     374,615     231,999     384,966
PARKER & PARSLEY 86-A, LTD.             6,075      11,653          --          --     446,620     856,663     452,695     868,316
PARKER & PARSLEY 86-B, LTD.            16,246      21,064          --          --     919,385   1,192,033     935,631   1,213,097
PARKER & PARSLEY 86-C, LTD.            11,745      16,465          --          --     886,520   1,242,812     898,265   1,259,277
PARKER & PARSLEY PRIVATE
  INVESTMENT 86, LTD.                   3,174       4,960          --          --     314,198     491,002     317,372     495,962
PARKER & PARSLEY 87-A CONV., LTD.       3,451       5,510          --          --     178,340     284,684     181,791     290,194
PARKER & PARSLEY 87-A, LTD.            21,378      34,166          --          --   1,313,604   2,099,440   1,334,982   2,133,606
PARKER & PARSLEY 87-B CONV., LTD.       2,988       4,431          --          --     245,753     364,425     248,741     368,856
PARKER & PARSLEY 87-B, LTD.            12,411      18,405          --          --   1,003,438   1,487,986   1,015,849   1,506,391
PARKER & PARSLEY PRODUCING
  PROPERTIES 87-A, LTD.                 9,632       9,615          --          --     704,591     703,402     714,223     713,017
PARKER & PARSLEY PRODUCING
  PROPERTIES 87-B, LTD.                13,937      22,316          --          --     523,830     838,757     537,767     861,073
PARKER & PARSLEY PRIVATE
  INVESTMENT 87, LTD.                   7,631       9,691          --          --     755,457     959,391     763,088     969,082
PARKER & PARSLEY 88-A CONV., L.P.       5,253       7,315          --          --     222,619     310,018     227,872     317,333
PARKER & PARSLEY 88-A, L.P.            18,059      25,149          --          --     758,976   1,056,963     777,035   1,082,112
PARKER & PARSLEY 88-B CONV., L.P.       4,220       5,515          --          --     269,028     351,572     273,248     357,087
PARKER & PARSLEY 88-B, L.P.            13,722      17,933          --          --     659,140     861,434     672,862     879,367
PARKER & PARSLEY 88-C CONV., L.P.       2,870       4,039          --          --     219,589     308,985     222,459     313,024
PARKER & PARSLEY 88-C, L.P.             1,908       2,685          --          --     156,634     220,398     158,542     223,083
PARKER & PARSLEY PRODUCING
  PROPERTIES 88-A, L.P                  7,216       9,530          --          --     420,265     555,001     427,481     564,531
PARKER & PARSLEY PRIVATE
  INVESTMENT 88, L.P.                   7,708       9,375          --          --     763,081     928,143     770,789     937,518
PARKER & PARSLEY 89-A CONV., L.P.       2,027       2,852          --          --     200,631     282,306     202,658     285,158
PARKER & PARSLEY 89-A, L.P.            13,556      19,075          --          --     588,978     828,781     602,534     847,856
PARKER & PARSLEY 89-B CONV., L.P.       5,782       7,927          --          --     434,277     595,395     440,059     603,322
PARKER & PARSLEY 89-B, L.P.             9,810      13,454          --          --     474,439     650,677     484,249     664,131
PARKER & PARSLEY PRIVATE
  INVESTMENT 89, L.P.                   7,311       7,715          --          --     461,062     486,555     468,373     494,270
PARKER & PARSLEY 90-A CONV., L.P.       2,145       2,701          --          --     132,990     167,459     135,135     170,160
PARKER & PARSLEY 90-A, L.P.            12,362      15,527          --          --     381,738     479,494     394,100     495,021
PARKER & PARSLEY 90-B CONV., L.P.      12,549      16,252          --          --     740,794     959,455     753,343     975,707
PARKER & PARSLEY 90-B, L.P.            25,709      33,227          --          --   2,023,300   2,615,035   2,049,009   2,648,262
PARKER & PARSLEY 90-C CONV., L.P.       6,507       6,522          --          --     460,152     461,213     466,659     467,735
PARKER & PARSLEY 90-C, L.P.             9,158       9,179          --          --     741,036     742,738     750,194     751,917
PARKER & PARSLEY PRIVATE
  INVESTMENT 90, L.P.                  12,668      12,480          --          --     809,113     797,112     821,781     809,592
PARKER & PARSLEY 90
  SPRABERRY PRIVATE DEV., L.P           4,177       3,814          --          --     413,544     377,597     417,721     381,411
PARKER & PARSLEY 91-A, L.P.            13,541      19,696          --          --     965,302   1,404,059     978,843   1,423,755
PARKER & PARSLEY 91-B, L.P.            11,335      13,334          --          --   1,030,441   1,212,237   1,041,776   1,225,571
                                    ---------   ---------      ------      ------  ----------  ----------  ----------  ----------
                TOTAL (D)           1,732,968   2,702,523      56,101      91,730  25,548,668  34,823,531  27,337,737  37,617,784
                                    =========   =========      ======      ======  ==========  ==========  ==========  ==========




----------

(a)      Represents Pioneer USA's partnership interests in each partnership as:
         (1) the sole or managing general partner of the partnership; (2) a
         limited partner of the partnership; and (3) the sole general partner of
         each nonmanaging general partner. Pioneer USA will not receive any
         Pioneer common stock or cash payment for its partnership interests in
         any participating partnership. However, as a result of the merger of
         each participating partnership, Pioneer USA will acquire 100% of the
         properties of the partnership including properties attributable to its
         partnership interests in the partnerships.

(b)      Represents four unaffiliated individuals' partnership interests as
         limited partners of each nonmanaging general partner. Excludes Pioneer
         USA's partnership interests as general partner of each nonmanaging
         general partner.

(c)      Represents the partnership interests of unaffiliated limited partners
         of each partnership. Excludes Pioneer USA's partnership interests as a
         limited partner of any partnership.

(d)      Corresponds to amounts in the reserve report prepared by Williamson
         Petroleum Consultants, Inc. as of December 31, 2000.


                                      A-12
   114

                                    TABLE 12

           PARTNERSHIP ESTIMATED RESERVES ATTRIBUTABLE TO PIONEER USA,
                NONMANAGING GENERAL PARTNERS AND LIMITED PARTNERS
                              AS OF MARCH 31, 2001






                                                                 TOTAL PARTNERSHIP ESTIMATED RESERVES
                                                       ---------------------------------------------------
                                                                                     NON MANAGING
                                                            PIONEER USA (a)       GENERAL PARTNERS (b)
                                                       -----------------------   -----------------------
                                                         OIL &                     OIL &
                                                       NGL (BBLS)   GAS (MCF)    NGL (BBLS)   GAS (MCF)
                                                       ----------   ----------   ----------   ----------
                                                                                  
PARKER & PARSLEY 81-I, LTD.                                44,015       89,859        3,183        6,506
PARKER & PARSLEY 81-II, LTD.                               34,163       51,620        1,399        2,115
PARKER & PARSLEY 82-I, LTD.                                82,220      182,248        2,887        6,397
PARKER & PARSLEY 82-II, LTD.                               83,829      124,152        2,621        3,875
PARKER & PARSLEY 82-III, LTD.                              70,421       67,391        2,308        2,201
PARKER & PARSLEY 83-A, LTD.                               214,832      320,743        8,496       12,685
PARKER & PARSLEY 83-B, LTD.                               275,618      448,098       10,813       17,579
PARKER & PARSLEY 84-A, LTD.                               285,567      482,485       12,603       21,293
PARKER & PARSLEY 85-A, LTD.                                 8,498       11,656           --           --
PARKER & PARSLEY 85-B, LTD.                                 3,895        5,745           --           --
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.              9,600       10,166           --           --
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.       5,008        8,464           --           --
PARKER & PARSLEY 86-A, LTD.                                 4,687        8,889           --           --
PARKER & PARSLEY 86-B, LTD.                                13,080       17,075           --           --
PARKER & PARSLEY 86-C, LTD.                                 8,652       11,999           --           --
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                2,479        3,864           --           --
PARKER & PARSLEY 87-A CONV., LTD.                           2,683        4,348           --           --
PARKER & PARSLEY 87-A, LTD.                                16,718       27,103           --           --
PARKER & PARSLEY 87-B CONV., LTD.                           2,359        3,531           --           --
PARKER & PARSLEY 87-B, LTD.                                 9,798       14,667           --           --
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.            7,415        7,413           --           --
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.           11,686       18,860           --           --
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                6,337        8,010           --           --
PARKER & PARSLEY 88-A CONV., L.P.                           4,229        5,872           --           --
PARKER & PARSLEY 88-A, L.P.                                14,541       20,192           --           --
PARKER & PARSLEY 88-B CONV., L.P.                           3,480        4,558           --           --
PARKER & PARSLEY 88-B, L.P.                                11,314       14,819           --           --
PARKER & PARSLEY 88-C CONV., L.P.                           2,345        3,297           --           --
PARKER & PARSLEY 88-C, L.P.                                 1,559        2,192           --           --
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.            6,055        7,923           --           --
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                6,543        7,829           --           --
PARKER & PARSLEY 89-A CONV., L.P.                           1,698        2,414           --           --
PARKER & PARSLEY 89-A, L.P.                                11,359       16,152           --           --
PARKER & PARSLEY 89-B CONV., L.P.                           4,604        6,368           --           --
PARKER & PARSLEY 89-B, L.P.                                 7,808       10,804           --           --
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                5,909        6,237           --           --
PARKER & PARSLEY 90-A CONV., L.P.                           1,744        2,199           --           --
PARKER & PARSLEY 90-A, L.P.                                 9,949       12,544           --           --
PARKER & PARSLEY 90-B CONV., L.P.                          10,224       13,186           --           --
PARKER & PARSLEY 90-B, L.P.                                20,923       26,947           --           --
PARKER & PARSLEY 90-C CONV., L.P.                           5,218        5,187           --           --
PARKER & PARSLEY 90-C, L.P.                                 7,344        7,301           --           --
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.               10,449       10,006           --           --
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.            3,482        3,172           --           --
PARKER & PARSLEY 91-A, L.P.                                11,647       16,716           --           --
PARKER & PARSLEY 91-B, L.P.                                 9,825       11,641           --           --
                                                       ----------   ----------   ----------   ----------
                  TOTAL                                 1,375,809    2,145,942       44,310       72,651
                                                       ==========   ==========   ==========   ==========



                                                                TOTAL PARTNERSHIP ESTIMATED RESERVES
                                                          -------------------------------------------------
                                                           LIMITED PARTNERS (c)             TOTAL
                                                          -----------------------   -----------------------
                                                            OIL &                    OIL &
                                                          NGL (BBLS)   GAS (MCF)    NGL (BBLS)    GAS (MCF)
                                                          ----------   ----------   ----------   ----------
                                                                                     
PARKER & PARSLEY 81-I, LTD.                                  119,464      242,599      166,662      338,964
PARKER & PARSLEY 81-II, LTD.                                 106,202      158,535      141,764      212,270
PARKER & PARSLEY 82-I, LTD.                                  174,292      386,652      259,399      575,297
PARKER & PARSLEY 82-II, LTD.                                 229,733      344,629      316,183      472,656
PARKER & PARSLEY 82-III, LTD.                                176,244      171,833      248,973      241,425
PARKER & PARSLEY 83-A, LTD.                                  585,852      874,674      809,180    1,208,102
PARKER & PARSLEY 83-B, LTD.                                  743,358    1,208,548    1,029,789    1,674,225
PARKER & PARSLEY 84-A, LTD.                                  822,057    1,388,920    1,120,227    1,892,698
PARKER & PARSLEY 85-A, LTD.                                  281,965      386,713      290,463      398,369
PARKER & PARSLEY 85-B, LTD.                                  222,731      328,479      226,626      334,224
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.               274,765      290,970      284,365      301,136
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.        181,256      306,332      186,264      314,796
PARKER & PARSLEY 86-A, LTD.                                  344,581      653,460      349,268      662,349
PARKER & PARSLEY 86-B, LTD.                                  740,201      966,261      753,281      983,336
PARKER & PARSLEY 86-C, LTD.                                  653,081      905,703      661,733      917,702
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                 245,444      382,576      247,923      386,440
PARKER & PARSLEY 87-A CONV., LTD.                            138,639      224,665      141,322      229,013
PARKER & PARSLEY 87-A, LTD.                                1,027,295    1,665,437    1,044,013    1,692,540
PARKER & PARSLEY 87-B CONV., LTD.                            193,991      290,404      196,350      293,935
PARKER & PARSLEY 87-B, LTD.                                  792,129    1,185,806      801,927    1,200,473
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.             542,443      542,313      549,858      549,726
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.             439,208      708,847      450,894      727,707
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                 627,335      792,961      633,672      800,971
PARKER & PARSLEY 88-A CONV., L.P.                            179,233      248,890      183,462      254,762
PARKER & PARSLEY 88-A, L.P.                                  611,107      848,608      625,648      868,800
PARKER & PARSLEY 88-B CONV., L.P.                            221,815      290,537      225,295      295,095
PARKER & PARSLEY 88-B, L.P.                                  543,481      711,836      554,795      726,655
PARKER & PARSLEY 88-C CONV., L.P.                            179,408      252,233      181,753      255,530
PARKER & PARSLEY 88-C, L.P.                                  127,978      179,932      129,537      182,124
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.             352,641      461,401      358,696      469,324
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                 647,747      775,098      654,290      782,927
PARKER & PARSLEY 89-A CONV., L.P.                            168,085      239,019      169,783      241,433
PARKER & PARSLEY 89-A, L.P.                                  493,498      701,759      504,857      717,911
PARKER & PARSLEY 89-B CONV., L.P.                            345,765      478,251      350,369      484,619
PARKER & PARSLEY 89-B, L.P.                                  377,628      522,545      385,436      533,349
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                 372,674      393,332      378,583      399,569
PARKER & PARSLEY 90-A CONV., L.P.                            108,108      136,309      109,852      138,508
PARKER & PARSLEY 90-A, L.P.                                  307,219      387,363      317,168      399,907
PARKER & PARSLEY 90-B CONV., L.P.                            603,559      778,404      613,783      791,590
PARKER & PARSLEY 90-B, L.P.                                1,646,642    2,120,743    1,667,565    2,147,690
PARKER & PARSLEY 90-C CONV., L.P.                            369,034      366,832      374,252      372,019
PARKER & PARSLEY 90-C, L.P.                                  594,276      590,739      601,620      598,040
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                 667,438      639,137      677,887      649,143
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.             344,669      314,060      348,151      317,232
PARKER & PARSLEY 91-A, L.P.                                  830,236    1,191,626      841,883    1,208,342
PARKER & PARSLEY 91-B, L.P.                                  893,203    1,058,325      903,028    1,069,966
                                                          ----------   ----------   ----------   ----------
                  TOTAL                                   20,647,710   28,094,296   22,067,829   30,312,889
                                                          ==========   ==========   ==========   ==========




----------


(a)  Represents Pioneer USA's partnership interests in each partnership as: (1)
     the sole or managing general partner of the partnership; (2) a limited
     partner of the partnership; and (3) the sole general partner of each
     nonmanaging general partner. Pioneer USA will not receive any Pioneer
     common stock or cash payment for its partnership interests in any
     participating partnership. However, as a result of the merger of each
     participating partnership, Pioneer USA will acquire 100% of the properties
     of the partnership including properties attributable to its partnership
     interests in the partnerships.

(b)  Represents four unaffiliated individuals' partnership interests as limited
     partners of each nonmanaging general partner. Excludes Pioneer USA's
     partnership interests as general partner of each nonmanaging general
     partner.

(c)  Represents the partnership interests of unaffiliated limited partners of
     each partnership. Excludes Pioneer USA's partnership interests as a limited
     partner of any partnership.





                                      A-13
   115



                                    TABLE 13

                   OIL, NATURAL GAS LIQUIDS AND GAS PRODUCTION
                  FOR THE THREE MONTHS ENDED MARCH 31, 2001 AND
           2000 AND THE YEARS ENDED DECEMBER 31, 2000, 1999 AND 1998





                                                                           OIL & NGL (BBLS)
                                                        --------------------------------------------------------------
                                                          FOR THE THREE MONTHS            FOR THE YEAR ENDED
                                                            ENDED MARCH 31,                   DECEMBER 31,
                                                        -----------------------   ------------------------------------
                                                           2001         2000         2000        1999          1998
                                                        ----------   ----------   ----------   ----------   ----------
                                                                                            
PARKER & PARSLEY 81-I, LTD.                                  2,927        3,619       13,976       14,970       13,937
PARKER & PARSLEY 81-II, LTD.                                 2,704        2,737       13,921       13,232       16,033
PARKER & PARSLEY 82-I, LTD.                                  5,318        6,243       24,158       23,886       25,898
PARKER & PARSLEY 82-II, LTD.                                 5,618        6,483       24,922       27,554       27,854
PARKER & PARSLEY 82-III, LTD.                                4,200        5,615       20,646       20,801       19,540
PARKER & PARSLEY 83-A, LTD.                                 13,844       16,424       66,679       69,238       67,612
PARKER & PARSLEY 83-B, LTD.                                 15,777       21,782       81,814       89,446       93,695
PARKER & PARSLEY 84-A, LTD.                                 20,020       21,791       85,485       85,868       88,702
PARKER & PARSLEY 85-A, LTD.                                  6,052        7,435       27,458       31,246       27,808
PARKER & PARSLEY 85-B, LTD.                                  4,994        4,993       20,809       21,410       24,803
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.               3,847        4,692       17,619       20,664       21,200
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.        3,732        3,625       15,698       14,598       15,439
PARKER & PARSLEY 86-A, LTD.                                  6,352        7,966       31,785       33,226       31,472
PARKER & PARSLEY 86-B, LTD.                                 11,736       15,880       62,337       63,132       70,399
PARKER & PARSLEY 86-C, LTD.                                 15,075       16,610       66,329       64,894       74,674
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                 4,163        5,424       20,938       20,843       22,245
PARKER & PARSLEY 87-A CONV., LTD.                            2,932        3,368       13,096       13,578       14,371
PARKER & PARSLEY 87-A, LTD.                                 21,902       25,185       97,824      101,441      107,375
PARKER & PARSLEY 87-B CONV., LTD.                            3,167        4,280       16,015       16,758       17,879
PARKER & PARSLEY 87-B, LTD.                                 12,941       17,478       65,401       68,433       73,036
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.            12,860       13,873       53,656       53,101       64,367
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.             7,142       10,018       33,115       35,770       40,796
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                 8,886        9,329       35,242       40,495       42,801
PARKER & PARSLEY 88-A CONV., L.P.                            3,883        3,496       14,604       17,052       16,899
PARKER & PARSLEY 88-A, L.P.                                 13,238       11,946       49,808       58,141       57,635
PARKER & PARSLEY 88-B CONV., L.P.                            3,683        4,667       18,572       16,986       17,610
PARKER & PARSLEY 88-B, L.P.                                  9,068       11,503       45,729       41,830       43,365
PARKER & PARSLEY 88-C CONV., L.P.                            3,111        3,815       15,453       14,136       14,859
PARKER & PARSLEY 88-C, L.P.                                  2,211        2,729       11,023       10,071       10,596
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.             6,273        6,060       26,976       30,280       34,491
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                 9,637       10,892       46,284       48,802       48,933
PARKER & PARSLEY 89-A CONV., L.P.                            3,016        3,150       13,092       14,166       14,102
PARKER & PARSLEY 89-A, L.P.                                  8,974        9,366       38,923       42,129       41,931
PARKER & PARSLEY 89-B CONV., L.P.                            6,485        7,859       30,959       32,585       35,481
PARKER & PARSLEY 89-B, L.P.                                  7,140        8,656       34,089       35,879       39,063
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                 7,528        7,721       30,738       30,310       36,741
PARKER & PARSLEY 90-A CONV., L.P.                            2,168        2,527        9,876       10,130       11,399
PARKER & PARSLEY 90-A, L.P.                                  6,265        7,290       28,519       29,248       32,915
PARKER & PARSLEY 90-B CONV., L.P.                           11,994       12,969       53,388       53,864       58,543
PARKER & PARSLEY 90-B, L.P.                                 32,546       35,197      144,804      146,064      158,775
PARKER & PARSLEY 90-C CONV., L.P.                            6,670        7,745       32,773       32,618       33,187
PARKER & PARSLEY 90-C, L.P.                                 10,718       12,449       52,686       52,433       53,358
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                11,435       13,108       52,913       46,335       49,468
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.             5,193        5,215       22,593       20,688       20,835
PARKER & PARSLEY 91-A, L.P.                                 13,120       16,199       64,129       64,820       70,623
PARKER & PARSLEY 91-B, L.P.                                 11,599       17,038       69,550       65,056       66,527
                                                        ----------    ---------  -----------   ----------   ----------
                  TOTAL                                    392,144      456,447    1,816,404    1,858,207    1,969,272
                                                        ==========    =========  ===========   ==========   ==========


                                                                               GAS (MCF)
                                                       -------------------------------------------------------------
                                                       FOR THE THREE MONTHS              FOR THE YEAR ENDED
                                                          ENDED MARCH 31,                   DECEMBER 31,
                                                       ----------------------   ------------------------------------
                                                         2001         2000          2000        1999          1998
                                                       ---------   ----------   ----------   ----------   ----------
                                                                                           
PARKER & PARSLEY 81-I, LTD.                                5,562        6,102       25,901       28,708       24,638
PARKER & PARSLEY 81-II, LTD.                               5,731        1,489       15,864       19,167       22,439
PARKER & PARSLEY 82-I, LTD.                               13,274       12,235       45,981       48,380       48,971
PARKER & PARSLEY 82-II, LTD.                              11,592        9,151       35,900       42,858       41,862
PARKER & PARSLEY 82-III, LTD.                              5,196        6,304       21,480       23,061       17,680
PARKER & PARSLEY 83-A, LTD.                               25,707       22,988       94,612      109,716       95,156
PARKER & PARSLEY 83-B, LTD.                               29,602       35,379      132,106      157,842      147,495
PARKER & PARSLEY 84-A, LTD.                               33,550       35,071      138,617      154,235      145,870
PARKER & PARSLEY 85-A, LTD.                               12,365       11,812       41,549       55,226       43,021
PARKER & PARSLEY 85-B, LTD.                                8,365        7,429       30,909       33,467       41,501
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.             4,506        5,061       20,905       23,218       22,343
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.      6,584        5,393       22,987       27,627       25,328
PARKER & PARSLEY 86-A, LTD.                               10,876       14,461       56,549       62,354       49,805
PARKER & PARSLEY 86-B, LTD.                               20,049       20,435       79,859       86,726       97,715
PARKER & PARSLEY 86-C, LTD.                               28,858       21,750       95,610      105,081      129,149
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.               8,951        7,936       33,570       30,923       33,219
PARKER & PARSLEY 87-A CONV., LTD.                          5,718        5,425       20,355       24,503       24,025
PARKER & PARSLEY 87-A, LTD.                               42,755       40,626      152,075      183,099      179,494
PARKER & PARSLEY 87-B CONV., LTD.                          4,549        6,437       23,682       24,436       25,477
PARKER & PARSLEY 87-B, LTD.                               18,570       26,331       96,740       99,771      104,072
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.          11,750        9,135       45,872       53,145       56,240
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.           9,834       14,555       49,380       48,774       50,220
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.              11,385       11,546       48,307       52,874       58,036
PARKER & PARSLEY 88-A CONV., L.P.                          8,645        4,685       21,399       27,417       25,367
PARKER & PARSLEY 88-A, L.P.                               29,495       15,987       72,965       93,498       86,501
PARKER & PARSLEY 88-B CONV., L.P.                          3,500        5,699       21,781       23,221       21,214
PARKER & PARSLEY 88-B, L.P.                                8,631       14,019       53,620       57,190       52,254
PARKER & PARSLEY 88-C CONV., L.P.                          3,530        4,769       19,618       21,119       19,764
PARKER & PARSLEY 88-C, L.P.                                2,517        3,392       13,979       15,049       14,091
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.           8,730        9,789       37,939       44,467       51,099
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.              14,638       15,649       59,532       66,701       61,718
PARKER & PARSLEY 89-A CONV., L.P.                          5,605        4,757       20,057       20,484       21,106
PARKER & PARSLEY 89-A, L.P.                               16,665       14,142       59,638       60,905       62,751
PARKER & PARSLEY 89-B CONV., L.P.                         12,480       11,218       42,179       46,681       52,345
PARKER & PARSLEY 89-B, L.P.                               13,738       12,352       46,454       51,400       57,643
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.              11,008        6,473       30,037       32,985       44,624
PARKER & PARSLEY 90-A CONV., L.P.                          4,098        3,430       13,365       14,989       16,309
PARKER & PARSLEY 90-A, L.P.                               11,838        9,897       38,570       43,302       47,086
PARKER & PARSLEY 90-B CONV., L.P.                         18,996       15,621       64,786       70,803       73,460
PARKER & PARSLEY 90-B, L.P.                               51,504       42,382      175,696      192,016      199,215
PARKER & PARSLEY 90-C CONV., L.P.                          8,151        6,434       30,423       29,399       30,348
PARKER & PARSLEY 90-C, L.P.                               13,106       10,341       48,907       47,265       48,787
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.              14,913       12,754       49,484       47,331       54,218
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.           8,177        3,949       22,121       19,579       24,095
PARKER & PARSLEY 91-A, L.P.                               19,051       22,979       94,315      100,615      108,617
PARKER & PARSLEY 91-B, L.P.                               10,623       19,802       85,556       74,025       68,244
                                                      ----------    ---------  -----------   ----------   ----------
                  TOTAL                                  634,968      607,571    2,451,231    2,695,632    2,724,612
                                                      ==========    =========  ===========   ==========   ==========



                                                                             TOTAL (BOE) (A)
                                                      --------------------------------------------------------------
                                                        FOR THE THREE MONTHS            FOR THE YEAR ENDED
                                                          ENDED MARCH 31,                 DECEMBER 31,
                                                      -----------------------   ------------------------------------
                                                         2001         2000         2000         1999         1998
                                                      ----------   ----------   ----------   ----------   ----------
                                                                                          
PARKER & PARSLEY 81-I, LTD.                                3,854        4,636       18,293       19,755       18,043
PARKER & PARSLEY 81-II, LTD.                               3,659        2,985       16,565       16,427       19,773
PARKER & PARSLEY 82-I, LTD.                                7,530        8,282       31,822       31,949       34,060
PARKER & PARSLEY 82-II, LTD.                               7,550        8,008       30,905       34,697       34,831
PARKER & PARSLEY 82-III, LTD.                              5,066        6,666       24,226       24,645       22,487
PARKER & PARSLEY 83-A, LTD.                               18,129       20,255       82,448       87,524       83,471
PARKER & PARSLEY 83-B, LTD.                               20,711       27,679      103,832      115,753      118,278
PARKER & PARSLEY 84-A, LTD.                               25,612       27,636      108,588      111,574      113,014
PARKER & PARSLEY 85-A, LTD.                                8,113        9,404       34,383       40,450       34,978
PARKER & PARSLEY 85-B, LTD.                                6,388        6,231       25,961       26,988       31,720
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.             4,598        5,536       21,103       24,534       24,924
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.      4,829        4,524       19,529       19,203       19,660
PARKER & PARSLEY 86-A, LTD.                                8,165       10,376       41,210       43,618       39,773
PARKER & PARSLEY 86-B, LTD.                               15,078       19,286       75,647       77,586       86,685
PARKER & PARSLEY 86-C, LTD.                               19,885       20,235       82,264       82,408       96,199
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.               5,655        6,747       26,533       25,997       27,782
PARKER & PARSLEY 87-A CONV., LTD.                          3,885        4,272       16,489       17,662       18,375
PARKER & PARSLEY 87-A, LTD.                               29,028       31,956      123,170      131,958      137,291
PARKER & PARSLEY 87-B CONV., LTD.                          3,925        5,353       19,962       20,831       22,125
PARKER & PARSLEY 87-B, LTD.                               16,036       21,867       81,524       85,062       90,381
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.          14,818       15,396       61,301       61,959       73,740
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.           8,781       12,444       41,345       43,899       49,166
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.              10,784       11,253       43,293       49,307       52,474
PARKER & PARSLEY 88-A CONV., L.P.                          5,324        4,277       18,171       21,622       21,127
PARKER & PARSLEY 88-A, L.P.                               18,154       14,611       61,969       73,724       72,052
PARKER & PARSLEY 88-B CONV., L.P.                          4,266        5,617       22,202       20,856       21,146
PARKER & PARSLEY 88-B, L.P.                               10,507       13,840       54,666       51,362       52,074
PARKER & PARSLEY 88-C CONV., L.P.                          3,699        4,610       18,723       17,656       18,153
PARKER & PARSLEY 88-C, L.P.                                2,631        3,294       13,353       12,579       12,945
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.           7,728        7,692       33,299       37,691       43,008
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.              12,077       13,500       56,206       59,919       59,219
PARKER & PARSLEY 89-A CONV., L.P.                          3,950        3,943       16,435       17,580       17,620
PARKER & PARSLEY 89-A, L.P.                               11,752       11,723       48,863       52,280       52,390
PARKER & PARSLEY 89-B CONV., L.P.                          8,565        9,729       37,989       40,365       44,205
PARKER & PARSLEY 89-B, L.P.                                9,430       10,715       41,831       44,446       48,670
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.               9,363        8,800       35,744       35,808       44,178
PARKER & PARSLEY 90-A CONV., L.P.                          2,851        3,099       12,104       12,628       14,117
PARKER & PARSLEY 90-A, L.P.                                8,238        8,940       34,947       36,465       40,763
PARKER & PARSLEY 90-B CONV., L.P.                         15,160       15,573       64,186       65,665       70,786
PARKER & PARSLEY 90-B, L.P.                               41,130       42,261      174,087      178,067      191,978
PARKER & PARSLEY 90-C CONV., L.P.                          8,029        8,817       37,844       37,518       38,245
PARKER & PARSLEY 90-C, L.P.                               12,902       14,173       60,837       60,311       61,489
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.              13,921       15,234       61,160       54,224       58,504
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.           6,556        5,873       26,280       23,951       24,851
PARKER & PARSLEY 91-A, L.P.                               16,295       20,029       79,848       81,589       88,726
PARKER & PARSLEY 91-B, L.P.                               13,370       20,338       83,809       77,394       77,901
                                                      ----------    ---------  -----------   ----------   ----------
                  TOTAL                                  497,977      557,715    2,224,946    2,307,486    2,423,377
                                                      ==========    =========  ===========   ==========   ==========





----------

(a) Gas production is converted to oil equivalents at the rate of six mcf per
barrel, representing the relative energy content of natural gas and oil.




                                      A-14
   116



                                    TABLE 14

                     PRODUCTIVE WELLS AND DEVELOPED ACREAGE
                              AS OF MARCH 31, 2001






                                                               PRODUCTIVE OIL AND
                                                                    GAS WELLS                  DEVELOPED ACRES
                                                            -------------------------     -------------------------
                                                             GROSS (a)       NET (b)      GROSS (a)       NET (b)
                                                            ----------     ----------     ----------     ----------
                                                                                             
PARKER & PARSLEY 81-I, LTD.                                         16           9.13          2,328          1,250
PARKER & PARSLEY 81-II, LTD.                                        12           8.40          1,563          1,050
PARKER & PARSLEY 82-I, LTD.                                         17          16.19          1,702          1,557
PARKER & PARSLEY 82-II, LTD.                                        16          15.38          1,882          1,489
PARKER & PARSLEY 82-III, LTD.                                       13          11.63          2,013          1,381
PARKER & PARSLEY 83-A, LTD.                                         42          36.59          5,154          3,602
PARKER & PARSLEY 83-B, LTD.                                         41          40.66          5,227          4,190
PARKER & PARSLEY 84-A, LTD.                                         38          37.55          4,929          4,019
PARKER & PARSLEY 85-A, LTD.                                         21          17.05          2,083          1,315
PARKER & PARSLEY 85-B, LTD.                                         17          13.05          2,536          1,215
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.                      11           7.78          1,204            658
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.               12           9.23          1,282            738
PARKER & PARSLEY 86-A, LTD.                                         26          21.86          1,689          1,108
PARKER & PARSLEY 86-B, LTD.                                         43          35.65          2,709          1,694
PARKER & PARSLEY 86-C, LTD.                                         53          44.36          4,432          2,786
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                        14          12.37          1,685          1,131
PARKER & PARSLEY 87-A CONV., LTD.                                   73           7.06          6,498            659
PARKER & PARSLEY 87-A, LTD.                                         73          52.76          6,498          4,926
PARKER & PARSLEY 87-B CONV., LTD.                                   48           8.13          4,465            796
PARKER & PARSLEY 87-B, LTD.                                         48          33.21          4,465          3,251
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.                    84          39.42         10,576          3,615
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.                    34          20.52          4,302          1,609
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                        24          19.65          1,685          1,130
PARKER & PARSLEY 88-A CONV., L.P.                                   39           8.01          3,286            592
PARKER & PARSLEY 88-A, L.P.                                         39          25.98          3,286          1,628
PARKER & PARSLEY 88-B CONV., L.P.                                   41           7.65          2,766            956
PARKER & PARSLEY 88-B, L.P.                                         41          18.82          2,766            412
PARKER & PARSLEY 88-C CONV., L.P.                                   41           6.97          2,757            343
PARKER & PARSLEY 88-C, L.P.                                         41           4.97          2,757            244
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.                    23          18.69          1,689          1,193
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                        22          19.18          1,873          1,211
PARKER & PARSLEY 89-A CONV., L.P.                                   31           5.73          2,811            553
PARKER & PARSLEY 89-A, L.P.                                         31          17.04          2,811          1,645
PARKER & PARSLEY 89-B CONV., L.P.                                   33          13.72          2,992          1,150
PARKER & PARSLEY 89-B, L.P.                                         33          15.12          2,992          1,267
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                        19          13.87          1,913          1,253
PARKER & PARSLEY 90-A CONV., L.P.                                   25           4.56          2,045            395
PARKER & PARSLEY 90-A, L.P.                                         25          13.17          2,045          1,141
PARKER & PARSLEY 90-B CONV., L.P.                                  103          23.18          9,729          2,086
PARKER & PARSLEY 90-B, L.P.                                        103          62.92          9,729          5,658
PARKER & PARSLEY 90-C CONV., L.P.                                   42          13.68          1,021            316
PARKER & PARSLEY 90-C, L.P.                                         42          21.99          1,021            509
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                        27          20.65          2,333          1,556
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.                    12           9.00          1,017            658
PARKER & PARSLEY 91-A, L.P.                                         47          24.71          4,389          1,891
PARKER & PARSLEY 91-B, L.P.                                         29          21.97          1,922          1,301
                                                              --------       --------       --------       --------
                               TOTAL                             1,665         909.21        150,857         73,127
                                                              ========       ========       ========       ========




----------

(a)      A "gross well" or "gross acre" is a well or an acre in which a working
         interest is owned. The number of gross wells or acres represents the
         sum of the wells or acres in which a working interest is owned.

(b)      A "net well" or "net acre" is deemed to exist when the sum of the
         fractional working interests in gross wells or acres equals one. The
         number of net wells or acres is the sum of the fractional working
         interests in gross wells or acres.





                                      A-15
   117



                                    TABLE 15

                   RECENT TRADES OF PARTNERSHIP INTERESTS (a)
                              PER $1,000 INVESTMENT
                  FOR THE THREE MONTHS ENDED MARCH 31, 2001 AND
                   THE YEARS ENDED DECEMBER 31, 2000 AND 1999







                                                                   PER $1,000 INVESTMENT
                                                   ------------------------------------------------------
                                                         FOR THE THREE MONTHS ENDED MARCH 31, 2001
                                                   -----------------------------------------------------
                                                           SALES PRICE
                                                   -------------------------     NUMBER         NUMBER
                                                      HIGH           LOW        OF SALES        SOLD
                                                   -----------   -----------   -----------   -----------
                                                                                 
PARKER & PARSLEY 82-1, LTD.                        $        --   $        --            --            --
PARKER & PARSLEY 82-11, LTD.                             75.00         75.00             2            20
PARKER & PARSLEY 83-A, LTD.                             120.00        110.00             3            55
PARKER & PARSLEY 83-B, LTD.                             137.00        117.50             2            20
PARKER & PARSLEY 84-A, LTD.                             152.00        143.56             3            70
PARKER & PARSLEY 85-A, LTD.                                 --            --            --            --
PARKER & PARSLEY 85-B, LTD.                             145.00        145.00             1            10
PARKER & PARSLEY 86-A, LTD.                             140.00        140.00             1            10
PARKER & PARSLEY 86-B, LTD.                             165.00        165.00             1             5
PARKER & PARSLEY 86-C, LTD.                             147.66        130.00             2            15
PARKER & PARSLEY 87-A, LTD.                             163.75        145.00             3           155
PARKER & PARSLEY 87-B, LTD.                             157.20        157.20             1             5
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.        280.00        280.00             1            20
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.        138.00        138.00             1             4
PARKER & PARSLEY 88-A, L.P.                             210.00        186.00             3            35
PARKER & PARSLEY 88-B, L.P.                                 --            --            --            --
PARKER & PARSLEY 88-C, L.P.                             250.00        250.00             2            90
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.            --            --            --            --
PARKER & PARSLEY 89-A, L.P.                             215.00        215.00             2            30
PARKER & PARSLEY 89-B, L.P.                                 --            --            --            --
PARKER & PARSLEY 90-A, L.P.                                 --            --            --            --
PARKER & PARSLEY 90-B, L.P.                             260.00        211.12             4            50
PARKER & PARSLEY 90-C, L.P.                             225.00        112.30             2            35
PARKER & PARSLEY 91-A, L.P.                             275.00        275.00             1            10
PARKER & PARSLEY 91-B, L.P.                                 --            --            --            --



                                                                 PER $1,000 INVESTMENT
                                                  -------------------------------------------------------
                                                           FOR THE YEAR ENDED DECEMBER 31, 2000
                                                  -----------------------------------------------------
                                                        SALES PRICE
                                                  -------------------------    NUMBER         NUMBER
                                                     HIGH          LOW         OF SALES        SOLD
                                                  -----------   -----------   -----------   -----------
                                                                                
PARKER & PARSLEY 82-1, LTD.                       $     47.75   $     37.50             5            61
PARKER & PARSLEY 82-11, LTD.                            89.00         45.00             6            60
PARKER & PARSLEY 83-A, LTD.                            112.50         94.00             6            60
PARKER & PARSLEY 83-B, LTD.                            135.00         96.11             5           105
PARKER & PARSLEY 84-A, LTD.                            165.00        101.11             8           175
PARKER & PARSLEY 85-A, LTD.                                --            --            --            --
PARKER & PARSLEY 85-B, LTD.                            135.00        100.00             4            35
PARKER & PARSLEY 86-A, LTD.                            160.00         65.00             4            45
PARKER & PARSLEY 86-B, LTD.                            160.00         97.00             8           120
PARKER & PARSLEY 86-C, LTD.                            135.00         95.45             4            40
PARKER & PARSLEY 87-A, LTD.                            163.75         78.00            12           128
PARKER & PARSLEY 87-B, LTD.                            179.25        105.66            14           255
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.       280.00        184.00             2            12
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.       310.00        146.00             3            47
PARKER & PARSLEY 88-A, L.P.                            205.00        135.00             6            43
PARKER & PARSLEY 88-B, L.P.                            188.12        128.00             3           230
PARKER & PARSLEY 88-C, L.P.                            175.00        138.20             4            17
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.           --            --            --            --
PARKER & PARSLEY 89-A, L.P.                            221.00        140.00             7           100
PARKER & PARSLEY 89-B, L.P.                            215.00        215.00             1             5
PARKER & PARSLEY 90-A, L.P.                            230.00        126.11             3            35
PARKER & PARSLEY 90-B, L.P.                            211.12        100.00            19           275
PARKER & PARSLEY 90-C, L.P.                            210.00        112.30            12           251
PARKER & PARSLEY 91-A, L.P.                            259.00        212.00             2            22
PARKER & PARSLEY 91-B, L.P.                            235.11        235.11             1            10



                                                                 PER $1,000 INVESTMENT
                                                  -------------------------------------------------------
                                                         FOR THE YEAR ENDED DECEMBER 31, 1999
                                                  -----------------------------------------------------
                                                         SALES PRICE
                                                  -------------------------     NUMBER        NUMBER
                                                      HIGH           LOW        OF SALES       SOLD
                                                  -----------   -----------   -----------   -----------
                                                                                
PARKER & PARSLEY 82-1, LTD.                       $     15.00   $      4.17             2            24
PARKER & PARSLEY 82-11, LTD.                            30.83         10.50             3            41
PARKER & PARSLEY 83-A, LTD.                             54.00         36.75            10           151
PARKER & PARSLEY 83-B, LTD.                             63.11         43.00             2            35
PARKER & PARSLEY 84-A, LTD.                             72.00         44.00             8           104
PARKER & PARSLEY 85-A, LTD.                             61.00         10.00             5            50
PARKER & PARSLEY 85-B, LTD.                             75.00         75.00             2            30
PARKER & PARSLEY 86-A, LTD.                             55.00         10.00             2            40
PARKER & PARSLEY 86-B, LTD.                            111.00         62.34             9           108
PARKER & PARSLEY 86-C, LTD.                             80.00         45.00             5            32
PARKER & PARSLEY 87-A, LTD.                            112.00         65.00            10           155
PARKER & PARSLEY 87-B, LTD.                            101.67         10.00            12           205
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.       175.00        112.00             4            79
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.       170.00        128.00             3            30
PARKER & PARSLEY 88-A, L.P.                            105.11         57.00             3            25
PARKER & PARSLEY 88-B, L.P.                            111.00         62.00             4            50
PARKER & PARSLEY 88-C, L.P.                             56.00         56.00             1            25
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.       225.00        225.00             1             4
PARKER & PARSLEY 89-A, L.P.                            138.00         86.00             5            70
PARKER & PARSLEY 89-B, L.P.                            146.11        105.00             5            85
PARKER & PARSLEY 90-A, L.P.                             92.00         84.33             2            25
PARKER & PARSLEY 90-B, L.P.                            175.00         90.00            12           115
PARKER & PARSLEY 90-C, L.P.                            136.33         60.51             8           125
PARKER & PARSLEY 91-A, L.P.                            121.00         88.00             2            13
PARKER & PARSLEY 91-B, L.P.                            135.00        135.00             1            10





----------

(a)      This table contains historical information about recent trades of
         partnership interests on a per $1,000 investment as determined from
         "The Partnership Spectrum." The price information represents the prices
         reported to have been paid to the sellers net of commissions paid by
         buyers. This information should not be relied upon as any indication of
         the price at which the partnership interests may trade. There may have
         been other secondary sale transactions in the partnership interests,
         although no information regarding any such transactions is available to
         Pioneer USA. Because the information regarding sale transactions in the
         partnership interests in this table is provided without verification by
         Pioneer USA and because the information provided does not reflect
         sufficient activity to cause the prices shown to be representative of
         the market values of the partnership interests, the information should
         not be relied upon as indicative of the ability of limited partners to
         sell their partnership interests in secondary sale transactions or as
         to the prices at which the partnership interests may be sold.




                                      A-16
   118



                                    TABLE 16

     RESERVE VALUE ATTRIBUTABLE TO PIONEER USA, NONMANAGING GENERAL PARTNERS
                              AND LIMITED PARTNERS
                              AS OF MARCH 31, 2001





                                                                                    TOTAL RESERVE VALUE
                                                           ---------------------------------------------------------------------
                                                                              NONMANAGING           LIMITED
                                                           PIONEER USA (b) GENERAL PARTNERS (c)   PARTNERS (d)        TOTAL
                                                           --------------  -------------------   --------------   --------------
                                                                                                      
PARKER & PARSLEY 81-I, LTD.                                $      233,228     $       16,900     $      627,135   $      877,263
PARKER & PARSLEY 81-II, LTD.                                      146,961              6,020            453,478          606,459
PARKER & PARSLEY 82-I, LTD.                                       393,196             13,799            834,595        1,241,590
PARKER & PARSLEY 82-II, LTD.                                      424,071             13,255          1,163,695        1,601,021
PARKER & PARSLEY 82-III, LTD.                                     313,019             10,254            785,449        1,108,722
PARKER & PARSLEY 83-A, LTD.                                       948,058             37,495          2,585,378        3,570,931
PARKER & PARSLEY 83-B, LTD.                                     1,236,570             48,512          3,335,105        4,620,187
PARKER & PARSLEY 84-A, LTD.                                     1,298,417             57,301          3,737,727        5,093,445
PARKER & PARSLEY 85-A, LTD.                                        39,856                 --          1,322,363        1,362,219
PARKER & PARSLEY 85-B, LTD.                                        19,449                 --          1,112,104        1,131,553
PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.                     49,589                 --          1,419,276        1,468,865
PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.              24,427                 --            884,085          908,512
PARKER & PARSLEY 86-A, LTD.                                        23,434                 --          1,722,717        1,746,151
PARKER & PARSLEY 86-B, LTD.                                        65,922                 --          3,730,534        3,796,456
PARKER & PARSLEY 86-C, LTD.                                        40,095                 --          3,026,477        3,066,572
PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.                       12,491                 --          1,236,632        1,249,123
PARKER & PARSLEY 87-A CONV., LTD.                                  13,737                 --            709,821          723,558
PARKER & PARSLEY 87-A, LTD.                                        86,204                 --          5,297,076        5,383,280
PARKER & PARSLEY 87-B CONV., LTD.                                  11,562                 --            950,922          962,484
PARKER & PARSLEY 87-B, LTD.                                        48,024                 --          3,882,724        3,930,748
PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.                   33,772                 --          2,470,550        2,504,322
PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.                   62,095                 --          2,333,847        2,395,942
PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.                       29,690                 --          2,939,297        2,968,987
PARKER & PARSLEY 88-A CONV., L.P.                                  21,059                 --            892,537          913,596
PARKER & PARSLEY 88-A, L.P.                                        72,408                 --          3,043,164        3,115,572
PARKER & PARSLEY 88-B CONV., L.P.                                  17,830                 --          1,136,555        1,154,385
PARKER & PARSLEY 88-B, L.P.                                        57,973                 --          2,784,810        2,842,783
PARKER & PARSLEY 88-C CONV., L.P.                                  11,955                 --            914,613          926,568
PARKER & PARSLEY 88-C, L.P.                                         7,948                 --            652,411          660,359
PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.                   31,168                 --          1,815,156        1,846,324
PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.                       33,947                 --          3,360,773        3,394,720
PARKER & PARSLEY 89-A CONV., L.P.                                   9,130                 --            903,870          913,000
PARKER & PARSLEY 89-A, L.P.                                        61,080                 --          2,653,766        2,714,846
PARKER & PARSLEY 89-B CONV., L.P.                                  23,101                 --          1,735,034        1,758,135
PARKER & PARSLEY 89-B, L.P.                                        39,166                 --          1,894,254        1,933,420
PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.                       29,689                 --          1,872,378        1,902,067
PARKER & PARSLEY 90-A CONV., L.P.                                   8,840                 --            548,022          556,862
PARKER & PARSLEY 90-A, L.P.                                        50,432                 --          1,557,365        1,607,797
PARKER & PARSLEY 90-B CONV., L.P.                                  52,858                 --          3,120,422        3,173,280
PARKER & PARSLEY 90-B, L.P.                                       108,063                 --          8,504,751        8,612,814
PARKER & PARSLEY 90-C CONV., L.P.                                  25,475                 --          1,801,539        1,827,014
PARKER & PARSLEY 90-C, L.P.                                        35,856                 --          2,901,292        2,937,148
PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.                       52,622                 --          3,361,143        3,413,765
PARKER & PARSLEY 90 SPRABERRY PRIVATE DEV., L.P.                   15,168                 --          1,501,657        1,516,825
PARKER & PARSLEY 91-A, L.P.                                        65,170                 --          4,645,707        4,710,877
PARKER & PARSLEY 91-B, L.P.                                        54,289                 --          4,935,469        4,989,758
                                                           --------------     --------------     --------------   --------------
                                TOTAL                      $    6,439,094     $      203,536     $  103,097,675   $  109,740,305
                                                           ==============     ==============     ==============   ==============





----------

(a)  The reserve value is one of the components of the merger value for each
     partnership and represents the present value of estimated future net
     revenues from the partnership's estimated oil and gas reserves as of March
     31, 2001. The present value was calculated using: (1) a five-year New York
     Mercantile Exchange, or NYMEX, futures price for oil and gas as of March
     31, 2001 with prices held constant after year five at the year five price,
     less standard industry adjustments, (2) historical operating costs adjusted
     only for those items affected by commodity prices, such as production taxes
     and ad valorem taxes, and (3) a 10.0% discount rate. For 2001, the oil and
     gas prices were based on the average NYMEX futures price for the nine-month
     period beginning on April 1, 2001 and ending December 31, 2001.

(b)  Represents Pioneer USA's partnership interests in each partnership as: (1)
     the sole or managing general partner of the partnership; (2) a limited
     partner of the partnership; and (3) the sole general partner of each
     nonmanaging general partner. Pioneer USA will not receive any Pioneer
     common stock or cash payment for its partnership interests in any
     participating partnership. However, as a result of the merger of each
     participating partnership, Pioneer USA will acquire 100% of the properties
     of the partnership including properties attributable to its partnership
     interests in the partnerships.

(c)  Represents four unaffiliated individuals' partnership interests as limited
     partners of each nonmanaging general partner. Excludes Pioneer USA's
     partnership interests as general partner of each nonmanaging general
     partner.

(d)  Represents the partnership interests of unaffiliated limited partners of
     each partnership. Excludes Pioneer USA's partnership interests as a limited
     partner of any partnership.



                                      A-17
   119

                                   APPENDIX B
                                       TO
                           PROXY STATEMENT/PROSPECTUS

                         [TO BE PROVIDED BY AMENDMENT]




                                      B-1
   120

                                   APPENDIX C
                                       TO
                           PROXY STATEMENT/PROSPECTUS

                            SUMMARY RESERVE REPORT OF
                     WILLIAMSON PETROLEUM CONSULTANTS, INC.
                              FOR THE PARTNERSHIPS
                             AS OF DECEMBER 31, 2000



April 10, 2001


Pioneer Natural Resources USA, Inc.
5205 North O'Connor Boulevard, Suite 1400
Irving, Texas  75039

Attention Board of Directors

Gentlemen:

Subject: Letter Report Including 46 Reports Prepared
         by Williamson Petroleum Consultants, Inc.
         for Pioneer Natural Resources USA, Inc.
         to the Interests of Limited Partners
         or the Converted Limited Partners
         in Various Parker & Parsley Partnerships
         Managed by Pioneer Natural Resources USA, Inc.
         Effective December 31, 2000
         for Disclosure to the
         Securities and Exchange Commission
         Williamson Project 0.8839

In accordance with your request, Williamson Petroleum Consultants, Inc.
(Williamson) has prepared this summary letter for inclusion in the proxy
statement to be distributed to the limited partners of the referenced
partnerships by Pioneer Natural Resources USA, Inc. (Pioneer USA). This letter
includes 46 Williamson reports prepared for Pioneer USA to the interests of the
limited partners or the converted limited partners in various Parker & Parsley
partnerships managed by Pioneer USA effective December 31, 2000 for disclosure
to the Securities and Exchange Commission (SEC). A listing of the 46 Williamson
reports is included as Exhibit I.


I. ESTIMATED RESERVES AND ESTIMATED FUTURE NET REVENUES

The total Williamson estimated net proved reserves that are attributable to the
evaluated interests of the 46 partnership reports are shown in Exhibit II and
were based on economic parameters and operating condition considered applicable
as of December 31, 2000 and may be used in disclosure to the SEC.

The present values of the estimated future net revenues from proved reserves
were calculated using a discount rate of 10.00 percent per annum and were
computed in accordance with the financial reporting requirements of the SEC and
are presented in Exhibit II.



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Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 2



At the request of Pioneer USA, Williamson used the Landmark graphics and
reserves and economics evaluation software, Aries, to prepare this summary
report. In evaluations of these properties prior to December 31, 1991,
Williamson utilized its proprietary software programs. No comparative tests have
been performed to determine the difference in evaluation results of either
reserves or revenue quantities that may occur solely as a result of the
differences in the programs nor has Williamson performed tests to determine the
accuracy of Aries. However, in accordance with the request made by Pioneer USA
and the general acceptance of Aries by the oil and gas industry, Williamson has
used Aries to prepare this report.


II.  DEFINITIONS OF SEC RESERVES(1)

The estimated reserves presented in this summary letter are net proved reserves,
including proved developed producing, proved developed nonproducing, and proved
undeveloped reserves, and were computed in accordance with the financial
reporting requirements of the SEC. In preparing these evaluations, no attempt
has been made to quantify the element of uncertainty associated with any
category. Reserves were assigned to each category as warranted. The definitions
of oil and gas reserves pursuant to the requirements of the Securities Exchange
Act are:

Proved Reserves(2)

Proved reserves are the estimated quantities of crude oil, natural gas, and
natural gas liquids which geological and engineering data demonstrate with
reasonable certainty to be recoverable in future years from known reservoirs
under the economic criteria employed and existing operating conditions, i.e.,
prices and costs as of the date the estimate is made. Prices and costs include
consideration of changes provided only by contractual arrangements but not on
escalations based upon an estimate of future conditions.

----------

(1)  For evaluations prepared for disclosure to the Securities and Exchange
     Commission, see SEC Accounting Rules. Commerce Clearing House, Inc. October
     1981, Paragraph 290, Regulation 210.4-10, p. 329.

(2)  Any variations to these definitions will be clearly stated in the report.




                                      C-2
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Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 3



A.   Reservoirs are considered proved if economic producibility is supported by
     either actual production or conclusive formation test. The area of a
     reservoir considered proved includes:

     1.   that portion delineated by drilling and defined by gas-oil and/or
          oil-water contacts, if any; and

     2.   the immediately adjoining portions not yet drilled, but which can be
          reasonably judged as economically productive on the basis of available
          geological and engineering data. In the absence of information on
          fluid contacts, the lowest known structural occurrence of hydrocarbons
          controls the lower proved limit of the reservoir.

B.   Reserves which can be produced economically through application of improved
     recovery techniques (such as fluid injection) are included in the "proved"
     classification when successful testing by a pilot project, or the operation
     of an installed program in the reservoir, provides support for the
     engineering analysis on which the project or program was based.

C.   Estimates of proved reserves do not include the following:

     1.   oil that may become available from known reservoirs but is classified
          separately as "indicated additional reserves";

     2.   crude oil, natural gas, and natural gas liquids, the recovery of which
          is subject to reasonable doubt because of uncertainty as to geology,
          reservoir characteristics, or economic factors;

     3.   crude oil, natural gas, and natural gas liquids, that may occur in
          undrilled prospects; and

     4.   crude oil, natural gas, and natural gas liquids, that may be recovered
          from oil shales, coal(3), gilsonite, and other such sources.

----------

(3)  According to Staff Accounting Bulletin 85, excluding certain coalbed
     methane gas.



                                      C-3
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Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 4



Proved Developed Reserves(4)

Proved developed reserves are reserves that can be expected to be recovered
through existing wells with existing equipment and operating methods. Additional
oil and gas expected to be obtained through the application of fluid injection
or other improved recovery techniques for supplementing the natural forces and
mechanisms of primary recovery should be included as "proved developed reserves"
only after testing by a pilot project or after the operation of an installed
program has confirmed through production response that increased recovery will
be achieved.

Proved Undeveloped Reserves

Proved undeveloped reserves are reserves that are expected to be recovered from
new wells on undrilled acreage, or from existing wells where a relatively major
expenditure is required for recompletion. Reserves on undrilled acreage shall be
limited to those drilling units offsetting productive units that are reasonably
certain of production when drilled. Proved reserves for other undrilled units
can be claimed only where it can be demonstrated with certainty that there is
continuity of production from the existing productive formation. Under no
circumstances should estimates for proved undeveloped reserves be attributable
to any acreage for which an application of fluid injection or other improved
recovery technique is contemplated, unless such techniques have been proved
effective by actual tests in the area and in the same reservoir.

----------

(4)  Williamson Petroleum Consultants, Inc. separates proved developed reserves
     into proved developed producing and proved developed nonproducing reserves.
     This is to identify proved developed producing reserves as those to be
     recovered from actively producing wells; proved developed nonproducing
     reserves as those to be recovered from wells or intervals within wells,
     which are completed but shut in waiting on equipment or pipeline
     connections, or wells where a relatively minor expenditure is required for
     recompletion to another zone.



                                      C-4
   124

Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 5



III.  DISCUSSION OF SEC RESERVES

The properties evaluated in this report are located in the states of Oklahoma
and Texas with the majority of the value in the Spraberry (Trend Area) field,
Texas.

The individual projections of lease reserves and economics prepared to produce
this summary report include data that describe the production forecasts and
associated evaluation parameters such as interests, taxes, product prices,
operating costs, investments, salvage values, abandonment costs, and net profit
interests.

Net income to the evaluated interests is the future net revenue after
consideration of royalty revenue payable to others, taxes, operating expenses,
investments, salvage values, abandonment costs, and net profit interests, as
applicable. The future net revenue is before federal income tax and excludes
consideration of any encumbrances against the properties if such exist.

The future net revenue values presented in this report were based on projections
of oil and gas production. It was assumed there would be no significant delay
between the date of oil and gas production and the receipt of the associated
revenue for this production. No opinion is expressed by Williamson in this
report as to a fair market value of the evaluated properties.

Unless specifically identified and documented by Pioneer USA as having
curtailment problems, gas production trends have been assumed to be a function
of well productivity and not of market conditions. The effect of "take or pay"
clauses in gas contracts was not considered.

Oil and natural gas liquids (NGL) reserves are expressed in thousands of United
States (U.S.) barrels (MBBL) of 42 U.S. gallons. Gas volumes are expressed in
millions of cubic feet (MMCF) at 60 degrees Fahrenheit and at the legal pressure
base that prevails in the state which the reserves are located. No adjustment of
the individual gas volumes to a common pressure base has been made.

This report includes only those costs and revenues which are considered by
Pioneer USA to be directly attributable to individual leases and areas. There
could exist other revenues, overhead costs, or other costs associated with
Pioneer USA or the Limited Partners/Converted Limited Partners which are not
included in this report. Such additional costs and revenues are outside the
scope of this report. This report is not a financial statement for Pioneer USA
or the Limited Partners/Converted Limited Partners and should not be used as the
sole basis for any transaction concerning Pioneer USA, the Limited
Partners/Converted Limited Partners, or the evaluated properties.




                                      C-5
   125

Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 6



The reserves projections in this report are based on the use of the available
data and accepted industry engineering methods. Future changes in any
operational or economic parameters or production characteristics of the
evaluated properties could increase or decrease their reserves. Unforeseen
changes in market demand or allowables set by various regulatory agencies could
also cause actual production rates to vary from those projected. Williamson
reserves the right to alter any of the reserves projections and the associated
economics included in this evaluation in any future evaluations based on
additional data that may be acquired.

All data utilized in the preparation of this report with respect to interests,
reversionary status, oil and gas prices, gas categories, gas contract terms,
operating expenses, investments, salvage values, abandonment costs, net profit
interests, well information, and current operating conditions, as applicable,
were provided by Pioneer USA. Production data provided by Pioneer USA were
utilized. The production data was generally through October 2000. All data have
been reviewed for reasonableness and, unless obvious errors were detected, have
been accepted as correct. It should be emphasized that revisions to the
projections of reserves and economics included in this report may be required if
the provided data are revised for any reason. No inspection of the properties
was made as this was not considered within the scope of this evaluation. No
investigation was made of any environmental liabilities that might apply to the
evaluated properties, and no costs are included for any possible related
expenses.

Since sufficient production history and other data were available, the estimates
of reserves contained in this report were determined by extrapolation of
historical production trends and in accordance with the Definitions of SEC
Reserves included in this summary letter report.

Prices for oil sold as of December 31, 2000 were provided by Pioneer USA to be
used at the effective date. These prices include adjustments for API gravity,
transportation, and any bonus paid. These adjustments were made by Pioneer USA.
After the effective date, prices were held constant for the life of the
properties. No attempt has been made to account for oil price fluctuations which
have occurred in the market subsequent to the effective date of this report.

Prices for gas sold as of December 31, 2000 were provided by Pioneer USA to be
used at the effective date. These prices include adjustments for British thermal
unit content, shrinkage due to NGL removal, transportation and handling charges,
and any other known differences between sales and produced volumes. These
adjustments were made by Pioneer USA. After the effective date, prices were held
constant for the life of the properties unless Pioneer USA indicated



                                      C-6
   126

Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 7




that changes were provided for by contract. All gas prices were applied to
projected wellhead volumes.

Prices for NGL sold as of December 31, 2000 were provided by Pioneer USA to be
used at the effective date. NGL reserves were projected as a separate stream
using a constant ratio (barrels of NGL/thousand cubic feet of gas) based on
historical yields. After the effective date, prices were held constant for the
life of the properties. No attempt has been made to account for price
fluctuations which have occurred in the market subsequent to the effective date
of this report.

It should be emphasized that with the current economic uncertainties,
fluctuation in market conditions could significantly change the economics of the
properties included in this report.

Operating expenses were provided by Pioneer USA and represented, when possible,
the latest available 12-month average of all recurring expenses which are
billable to the working interest owners. These expenses included, but were not
limited to, all direct operating expenses, field overhead costs, and any ad
valorem taxes not deducted separately. Expenses for workovers, well
stimulations, and other maintenance were not included in the operating expenses
unless such work was expected on a recurring basis. Judgments for the exclusion
of the nonrecurring expenses were made by Pioneer USA. Operating costs were held
constant for the life of the properties.

State production and county ad valorem taxes have been deducted at the published
rates as provided by Pioneer USA. A 7.5 percent severance tax exemption was
applied until September 2001 for qualifying wells.

IV.  CONSENT AND DECLARATION OF INDEPENDENT STATUS

We understand that our estimates are to be included in a Schedule 13e-3 under
the Securities Exchange Act of 1934 to be filed by you with the SEC and in the
proxy statement included as an exhibit to such Schedule 13e-3. We understand
further that the estimates may be used by you to establish merger values for the
Partnerships. With this understanding in mind, we have consistently applied the
generally accepted petroleum engineering and evaluation principles in estimating
the proved oil and gas reserves and in computing the future net revenues derived
from such reserves for each property attributable to the interests held by the
Partnerships.

Based on information supplied by Pioneer USA, neither capital costs nor salvage
values were included in the projections of reserves and economics in this
report.

Williamson is an independent consulting firm and does not own any interests in
the oil and gas properties covered by this report. No employee, officer, or
director of Williamson is an employee, officer, or director of Pioneer USA or
any of the



                                      C-7
   127

Pioneer Natural Resources USA, Inc.
Board of Directors
April 10, 2001
Page 8



subject partnerships. Neither the employment of nor the compensation received by
Williamson is contingent upon the values assigned to the properties covered by
this report.

Yours very truly,

/s/ Williamson Petroleum Consultants, Inc.

WILLIAMSON PETROLEUM CONSULTANTS, INC.

JDS/chk

Enclosures




                                      C-8
   128

                                    EXHIBIT I

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

             LIST OF WILLIAMSON PETROLEUM CONSULTANTS, INC. REPORTS
                           EFFECTIVE DECEMBER 31, 2000

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 81-I, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 81-II, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 82-I, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 82-II, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 82-III, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 83-A, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 83-B, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 84-A, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 85-A, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 85-B, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"



                                      C-9
   129
                                    EXHIBIT I

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

             LIST OF WILLIAMSON PETROLEUM CONSULTANTS, INC. REPORTS
                           EFFECTIVE DECEMBER 31, 2000


"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Private Investment 85-A, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Selected 85 Private Investment, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 86-A, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 86-B, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 86-C, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Private Investment 86, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 87-A Converted, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 87-A, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 87-B Converted, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 87-B, Ltd. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"



                                      C-10
   130
                                    EXHIBIT I

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

             LIST OF WILLIAMSON PETROLEUM CONSULTANTS, INC. REPORTS
                           EFFECTIVE DECEMBER 31, 2000


"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Producing Properties 87-A, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Producing Properties 87-B, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Private Investment 87, Ltd. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 88-A Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 88-A, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 88-B Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 88-B, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 88-C Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 88-C, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"



                                      C-11
   131
                                    EXHIBIT I

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

             LIST OF WILLIAMSON PETROLEUM CONSULTANTS, INC. REPORTS
                           EFFECTIVE DECEMBER 31, 2000


"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Producing Properties 88-A, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Private Investment 88, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 89-A Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 89-A, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 89-B Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 89-B, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Private Investment 89, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 90-A Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 90-A, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"




                                      C-12
   132
                                    EXHIBIT I

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

             LIST OF WILLIAMSON PETROLEUM CONSULTANTS, INC. REPORTS
                           EFFECTIVE DECEMBER 31, 2000


"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 90-B Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 90-B, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Converted Limited
Partners in Parker & Parsley 90-C Converted, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 90-C, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley Private Investment 90, L.P. Managed by Pioneer Natural
Resources USA, Inc. Effective December 31, 2000 for Disclosure to the Securities
and Exchange Commission Summary Report Utilizing Aries Software Williamson
Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 90 Spraberry Private Development, L.P. Managed by Pioneer
Natural Resources USA, Inc. Effective December 31, 2000 for Disclosure to the
Securities and Exchange Commission Summary Report Utilizing Aries Software
Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 91-A, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"

"Evaluation of Oil and Gas Reserves to the Interests of the Limited Partners in
Parker & Parsley 91-B, L.P. Managed by Pioneer Natural Resources USA, Inc.
Effective December 31, 2000 for Disclosure to the Securities and Exchange
Commission Summary Report Utilizing Aries Software Williamson Project 0.8839"




                                      C-13
   133

                                   EXHIBIT II

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

                       NET RESERVES AND FUTURE NET REVENUE
         FROM REPORTS PREPARED BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                           EFFECTIVE DECEMBER 31, 2000




                                                                      TOTAL PROVED DEVELOPED PRODUCING
                                            ---------------------------------------------------------------------------------
                                                                                                  FUTURE NET REVENUE, M$
                                                        NET RESERVES TO                       -------------------------------
                                                     THE EVALUATED INTERESTS                                    DISCOUNTED
                                            --------------------------------------------                            PER
                                            OIL/CONDENSATE       LIQUID           GAS                            ANNUM AT
PIONEER FUNDS                                   (MBBL)           (MBBL)          (MMCF)       UNDISCOUNTED     10.00 PERCENT
-------------                               --------------      -------         --------      -------------    --------------
                                                                                                
Parker & Parsley 81-I, Ltd                      99.997           58.388          320.081        2,810.911        1,436.523
Parker & Parsley 81-II, Ltd.                    84.731           67.440          222.749        1,977.257        1,062.283
Parker & Parsley 82-I, Ltd.                    194.780           73.613          603.859        4,656.049        2,419.619
Parker & Parsley 82-II, Ltd.                   211.725           94.426          467.740        4,879.008        2,416.761
Parker & Parsley 82-III, Ltd.                  164.851           68.468          223.717        2,916.207        1,539.389
Parker & Parsley 83-A, Ltd.                    497.915          281.533        1,156.089       11,168.739        5,649.205
Parker & Parsley 83-B, Ltd.                    608.901          345.775        1,553.450       14,112.492        7,165.928
Parker & Parsley 84-A, Ltd.                    608.956          403.376        1,678.388       15,623.823        7,676.646
Parker & Parsley 85-A, Ltd.                    243.615          134.904          512.744        5,195.717        2,783.387
Parker & Parsley 85-B, Ltd.                    201.444           99.966          455.062        4,490.151        2,308.454
Parker & Parsley Private
  Investment  85-A, Ltd.                       228.363           96.999          353.440        5,194.664        2,383.495
Parker & Parsley Selected
  85 Private Investment, Ltd.                  130.193           99.486          381.116        3,650.520        1,810.634
Parker & Parsley 86-A, Ltd.                    250.327          197.841          859.633        7,179.394        3,574.162
Parker & Parsley 86-B, Ltd.                    618.084          308.191        1,200.966       14,120.080        7,029.228
Parker & Parsley 86-C, Ltd.                    563.752          325.531        1,246.684       11,898.910        6,501.998
Parker & Parsley Private
  Investment 86, Ltd.                          208.138          106.060          491.002        4,920.619        2,468.192
Parker  & Parsley 87-A Conv., Ltd.             113.696           66.277          287.292        2,873.802        1,450.827
Parker & Parsley 87-A, Ltd                     834.588          487.044        2,112.270       21,154.029       10,747.196
Parker & Parsley 87-B Conv., Ltd.              157.541           88.713          365.167        3,907.545        1,832.825
Parker & Parsley 87-B, Ltd.                    643.391          362.299        1,491.327       15,958.265        7,485.189
Parker & Parsley Producing
  Properties 87-A, Ltd.                        553.134          153.947          705.887        9,228.521        4,636.341
Parker & Parsley Producing
  Properties 87-B, Ltd.                        348.562          183.827          852.462        9,400.038        4,368.675
Parker & Parsley Private
  Investment 87, Ltd.                          525.646          229.811          959.391       12,336.452        5,141.312
Parker & Parsley 88-A Conv., L.P.              144.189           81.404          314.160        3,480.240        1,705.478
Parker & Parsley 88-A, L.P.                    491.675          277.590        1,071.291       11,868.418        5,816.075
Parker & Parsley 88-B Conv., L.P.              185.600           84.916          353.516        4,354.398        2,077.136
Parker & Parsley 88-B, L.P.                    457.018          209.116          870.573       10,723.127        5,115.146
Parker & Parsley 88-C Conv., L.P.              145.815           74.419          309.894        3,561.005        1,706.767



                                      C-14
   134
                                   EXHIBIT II

                   LETTER REPORT INCLUDING 46 REPORTS PREPARED
                    BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                     FOR PIONEER NATURAL RESOURCES USA, INC.
                      TO THE INTERESTS OF LIMITED PARTNERS
                        OR THE CONVERTED LIMITED PARTNERS
                    IN VARIOUS PARKER & PARSLEY PARTNERSHIPS
                 MANAGED BY PIONEER NATURAL RESOURCES USA, INC.
                           EFFECTIVE DECEMBER 31, 2000
                              FOR DISCLOSURE TO THE
                       SECURITIES AND EXCHANGE COMMISSION
                            WILLIAMSON PROJECT 0.8839

                       NET RESERVES AND FUTURE NET REVENUE
         FROM REPORTS PREPARED BY WILLIAMSON PETROLEUM CONSULTANTS, INC.
                           EFFECTIVE DECEMBER 31, 2000




                                                                      TOTAL PROVED DEVELOPED PRODUCING
                                            ---------------------------------------------------------------------------------
                                                                                                  FUTURE NET REVENUE, M$
                                                        NET RESERVES TO                       -------------------------------
                                                     THE EVALUATED INTERESTS                                    DISCOUNTED
                                            --------------------------------------------                            PER
                                            OIL/CONDENSATE       LIQUID           GAS                            ANNUM AT
PIONEER FUNDS                                   (MBBL)           (MBBL)          (MMCF)       UNDISCOUNTED     10.00 PERCENT
-------------                               --------------      -------         --------      -------------    --------------
                                                                                                
Parker & Parsley 88-C, L.P.                    103.921           53.036          220.852        2,537.908        1,216.403
Parker & Parsley Producing
  Properties 88-A, L.P.                        273.838          149.368          558.886        6,727.211        3,225.257
Parker & Parsley Private
  Investment 88, L.P.                          509.333          253.748          928.143       12,668.293        5,826.092
Parker & Parker  89-A Conv., L.P.              136.107           64.524          282.306        3,433.908        1,667.718
Parker & Parsley 89-A, L.P.                    404.668          191.841          839.377       10,210.849        4,959.027
Parker & Parsley 89-B Conv., L.P.              276.640          159.018          597.289        6,717.103        3,379.724
Parker & Parsley 89-B, L.P.                    304.369          175.038          657.490        7,386.746        3,718.741
Parker & Parsley Private
  Investment 89, L.P.                          324.948          138.741          489.327        6,929.194        3,302.639
Parker & Parsley 90-A Conv., L.P.               86.964           46.820          168.458        2,004.818        1,042.228
Parker & Parsley 90-A, L.P.                    253.836          136.323          490.071        5,806.774        3,011.223
Parker & Parsley 90-B Conv., L.P.              503.298          242.511          965.950       11,527.923        5,694.202
Parker & Parsley 90-B, L.P.                  1,370.202          658.317        2,621.779       31,316.135       15,461.210
Parker & Parsley 90-C Conv., L.P.              323.794          138.198          463.058        6,302.167        3,212.933
Parker & Parsley 90-C, L.P.                    520.528          222.164          744.398       10,131.499        5,165.181
Parker  & Parsley Private
  Investment 90, L.P.                          584.599          228.964          801.496       12,370.155        5,691.401
Parker & Parsley 90
  Spraberry Private Development, L.P.          313.028          100.516          377.597        5,906.691        2,549.362
Parker & Parsley 91-A, L.P.                    662.796          306.258        1,409.517       17,786.756        8,134.929
Parker & Parsley 91-B, L.P.                    719.664          311.695        1,213.315       17,109.740        8,280.085
                                            ----------        ---------       ----------      -----------      -----------
Total All Partnerships                      17,189.160        8,638.440       35,249.259      400,514.251      195,847.226






                                      C-15
   135

                                   APPENDIX D
                                       TO
                           PROXY STATEMENT/PROSPECTUS

                                     FORM OF
                FAIRNESS OPINION OF ROBERT A. STANGER & CO., INC.
                               (SUBJECT TO CHANGE)

                                                         , 2001


Board of Directors of
Pioneer Natural Resources USA, Inc.,
As the Sole or Managing General Partner of
The Partnerships Identified on Exhibit I
1400 Williams Square West
5205 North O'Connor Boulevard
Irving, Texas 75039

Gentlemen:


         Pioneer Natural Resources USA, Inc. ("Pioneer USA"), the sole or
managing general partner of the partnerships identified in Exhibit I attached
hereto ("the Partnerships"), has advised us that the Partnerships are
contemplating a transaction (the "Transaction") pursuant to an agreement (the
"Merger Agreement") in which the Partnerships will merge with and into Pioneer
USA and the interests of the limited partners (the "Limited Partners") in each
Partnership will be converted into the right to receive shares of common stock
(the "Pioneer Parent Shares") of Pioneer Natural Resources Company ("Pioneer
Parent") equal to the estimated value of such Partnership's oil and gas reserves
(the "Reserve Value") and net working capital (the "Working Capital Balance") as
of March 31, 2001 (collectively, the Reserve Value and the Working Capital
Balance are referred to herein as the "Merger Value"). We have been advised that
the Merger Value will be allocated and paid to holders of limited partnership
interests (the "Limited Partner Interests") of each Partnership in accordance
with the provisions of the Partnership agreement of each Partnership relating to
a liquidation of the Partnership.

         We have been further advised that the Reserve Value has been
established by Pioneer USA and its parent company, Pioneer Parent, based upon
the present value of estimated future net revenues (after certain expenses and
charges) from each Partnership's proved oil and gas reserves as of March 31,
2001 utilizing prices for 2001, 2002, 2003, 2004 and thereafter of $26.17,
$24.36, $22.83, $22.31 and $21.97 per barrel of oil and $5.18, $4.61, $4.16,
$4.09 and $4.12 per thousand cubic feet of gas, and a discount rate of 10.0%.
[We have been further advised that the Reserve Value is based upon the reserve
report of Pioneer USA and Pioneer Parent, as reviewed by Williamson Petroleum
Consultants, Inc. ("Williamson"), an independent petroleum engineering firm, as
of March 31, 2001, and to which Pioneer USA and Pioneer Parent applied the
prices previously stated (the "Reserve Analysis").]

         We have been advised that the Limited Partners in each Partnership will
have the opportunity to approve or reject the participation by their Partnership
in the Transaction pursuant to a proxy statement/prospectus (the "Proxy
Statement/Prospectus") and a Limited Partners meeting which will be prepared and
held, respectively, in connection with the Transaction, and further that Limited
Partners in each Partnership, in exchange for Limited Partner Interests, will




                                      D-1
   136

receive the allocated Merger Value in Pioneer Parent Shares. We have been
advised that the value to be ascribed to each share of Pioneer Parent, which is
listed on the New York Stock Exchange ("NYSE"), shall be equal to the average
closing price for such shares on the NYSE for the ten trading day period ending
three business days prior to the initial meeting of the Limited Partners
contemplated herein.


         You have requested that Robert A. Stanger & Co., Inc. ("Stanger")
provide an opinion as to the fairness from a financial point of view to the
unaffiliated Limited Partners of each Partnership and the unaffiliated limited
partners of the non-managing general partner of each applicable Partnership of
the Merger Value ascribed to each Partnership and the allocation thereof to: (i)
the Limited Partners of each Partnership, as a group; (ii) the general partners
of each Partnership as a group; (iii) Pioneer USA, as the managing or sole
general partner of each partnership; (iv) the unaffiliated Limited Partners of
each Partnership, as a group; and (v) the unaffiliated limited partners of the
non-managing general partner of each applicable Partnership as a group.

         Stanger, founded in 1978, has provided research, investment banking and
consulting services to clients located throughout the United States, including
major New York Stock Exchange member firms and insurance companies and over
seventy companies engaged in the management and operations of partnerships. The
investment banking activities of Stanger include financial advisory services,
asset and securities valuations, industry and company research and analysis,
litigation support and expert witness services, and due diligence investigations
in connection with both publicly registered and privately placed securities
transactions.

         Stanger, as part of its investment banking business, is regularly
engaged in the valuation of securities in connection with mergers, acquisitions,
and reorganizations and for estate, tax, corporate and other purposes. In
particular, Stanger's valuation practice principally involves partnerships,
partnership securities and assets typically owned through partnerships
including, but not limited to, oil and gas reserves, real estate, mortgages
secured by real estate, cable television systems, and equipment leasing assets.

         In arriving at the opinion set forth below, we have:

         o    Reviewed the Preliminary Proxy Statement/Prospectus;

         o    Reviewed a draft of the Merger Agreement which Pioneer USA has
              indicated to be in substantially the form which will be executed
              in connection with the Transaction;

         o    Reviewed the financial statements and forms 10K and 10Q, as
              applicable, of the Partnerships for the years ended December 31,
              1998, 1999 and 2000, and the three months ended March 31, 2001;


         o    [Reviewed the Reserve Report for each Partnership reviewed by
              Williamson Petroleum Consultants, Inc. as of March 31, 2001;]



                                      D-2
   137


         o    Reviewed the calculations prepared by Pioneer USA and Pioneer
              Parent of the Merger Value per $1,000 original investment in each
              Partnership;


         o    Reviewed Pioneer USA's analysis of other alternatives to the
              Transaction including going concern value, liquidation value,
              royalty trust and production payment;


         o    Reviewed estimates prepared by Pioneer USA and Pioneer Parent of
              the going-concern value and liquidation value per $1,000 original
              investment in each Partnership;


         o    Interviewed key management personnel of Pioneer USA regarding the
              oil and gas reserves, the financial condition of each Partnership
              and the terms of the Transaction;


         o    Reviewed the financial statements of Pioneer Parent for the years
              ended December 31, 1999 and 2000 and the three months ended March
              31, 2001;

         o    Reviewed pro forma financial data for Pioneer Parent assuming the
              completion of the transaction;


         o    Reviewed recent secondary market trading activity for interests in
              the Partnerships, as available;


         o    Reviewed recent trading activity in Pioneer Parent Shares; and


         o    Conducted such other studies, analyses, inquiries and
              investigations as we deemed appropriate.


         In rendering this opinion, we have relied, without independent
verification, on the accuracy and completeness in all material respects of all
financial and other information that was furnished or otherwise communicated to
us by Pioneer USA, Pioneer Parent and the Partnerships. We have been advised by
Pioneer USA and Pioneer Parent that the oil and gas properties owned by the
Partnerships are subject to operating agreements (the "Operating Agreements")
with Pioneer USA and that: (i) such Operating Agreements provide for the payment
of overhead charges and that such charges are reasonable compared to amounts
charged for similar services by third-party operators; and (ii) except for
cause, such Operating Agreements do not provide for the termination of Pioneer
USA as operator, and (iii) such Operating Agreements do not provide for the
revision of overhead charges, except as escalated under the terms of such
Operating Agreements. Furthermore, we have been advised by Pioneer USA and
Pioneer Parent that if each Partnership's reserves were offered for sale to a
third party, a condition of such sale would be that the oil and gas reserves
would continue to be subject to the Operating Agreements with Pioneer USA which
provide for the payment of overhead charges, and that it would be appropriate to
assume, when estimating the value of such reserves, that such charges would
continue. We have also been advised that the Reserve Value and Working Capital
Balance of each Partnership has been properly allocated between Pioneer USA, the
other general partners, if any, and Limited Partners of each Partnership in
accordance with the Partnership Agreement with respect to a liquidation of such
Partnership.




                                      D-3
   138


         We have not performed an independent appraisal of the oil and gas
reserves or other assets and liabilities of the Partnerships. [We have not
conducted any engineering studies and have relied on estimates of Pioneer USA
and Pioneer Parent, which were reviewed by Williamson Petroleum Consultants,
Inc., with respect to oil and gas reserve volumes, prices, operating costs, and
overhead charges.]

         We have relied on the assurance of Pioneer USA, Pioneer Parent and the
Partnerships that: (i) the Reserve Analysis provided to us was in the judgment
of Pioneer USA and the Partnerships reasonably prepared on bases consistent with
actual historical experience and reflect their best currently available
estimates and good faith judgments; (ii) any estimates of costs to remediate
environmental conditions included in the Reserve Analysis are based on detailed
analyses and reflect the best currently available estimates and good faith
judgments; (iii) any historical financial data, balance sheet data, transaction
cost estimates, Merger Value analyses, going-concern value analyses and
liquidation value analyses are accurate and complete in all material respects;
(iv) all allocations included within the calculations of Merger Values,
going-concern values and liquidation values have been made in accordance with
the Partnership Agreement for each Partnership; (v) no material changes have
occurred in the information reviewed or in the value of the oil and gas reserves
or Working Capital Balances of each Partnership between the date the information
was provided to us and the date of this letter; (vi) the relative ownership
interest of the Limited Partners, unaffiliated Limited Partners, general
partners, unaffiliated limited partners of the non-managing general partner of
each applicable Partnership and Pioneer USA, as manager or sole general partner,
is accurately included in accordance with the Partnership Agreements on the
analyses provided to us by Pioneer USA; (vii) neither Pioneer Parent or any of
its affiliates has during the thirty days prior to the date hereof commenced or
continued a share repurchase program or similar transaction which could affect
the Pioneer Parent Share price to be used in the Transaction; and (viii) Pioneer
USA, Pioneer Parent and the Partnerships are not aware of any information or
facts regarding the Partnerships, the oil and gas properties, the Reserve
Analysis or the Working Capital Balances of each Partnership that would cause
the information supplied to us to be incomplete or misleading in any material
respect.

         We have not been requested to, and therefore did not: (i) make any
recommendation to Pioneer USA, the Partnerships or the Limited Partners with
respect to whether to approve or reject the Transaction; (ii) determine or
negotiate the amount or form of the Merger Value to be paid for Limited Partner
Interests in the Transaction; (iii) offer the assets of the Partnerships for
sale to any third party; (iv) express any opinion as to: (a) the impact of the
Transaction with respect to Pioneer USA or the Limited Partners of any
Partnerships that do not participate in the Transaction; (b) the tax
consequences of the Transaction for Pioneer USA, other general partners or the
Limited Partners of any Partnership; (c) Pioneer USA's or Pioneer Parent's
ability to finance their obligations pursuant to the Merger Agreement or the
impact of a failure to obtain financing on the financial performance of Pioneer
USA, Pioneer Parent or the Partnerships; (d) Pioneer USA's decision to estimate
the Reserve Value of the oil and gas reserves of each Partnership based upon the
continued operation of the properties by Pioneer USA and the payment of overhead
charges in accordance with existing Operating Agreements or the impact, if any,
on the estimated values of the Partnerships' oil and gas reserves if Pioneer USA
and Pioneer Parent determined to offer or operate the assets subject to revised
Operating Agreements; (e) whether or not alternative methods of determining the
Merger Value would have also provided fair results or results substantially
similar to the methodology used; (f) alternatives to the





                                      D-4
   139


Transaction, including the offering of such assets for sale to third-party
buyers; (g) the trading price of Pioneer Parent Shares immediately following the
closing of the Transaction and the distribution of Pioneer Parent Shares in
connection therewith; (h) the fairness of the termination of the repurchase
obligations of Pioneer USA with respect to those partnerships wherein Pioneer
USA is obligated to offer to repurchase limited partnership interests annually
based upon a formula which, in certain circumstances including the repurchase
offers based upon December 31, 2000 oil and gas prices, result in repurchase
offer prices above the market value for the reserves of such Partnerships; or
(i) any other terms of the Transaction.


         This letter does not purport to be a complete description of the
analyses performed or the matters considered in rendering this opinion. The
analyses and the summary set forth herein must be considered as a whole, and
selecting portions of such summary or analyses without considering all factors
and analyses would create an incomplete view of the process underlying this
opinion. In rendering this opinion, judgment was applied to a variety of complex
analyses and assumptions. The assumptions made and the judgments applied in
rendering the opinion are not readily susceptible to partial analysis or summary
description. The fact that any specific analysis is referred to herein is not
meant to indicate that such analysis was given greater weight than any other
analyses.

         Our opinion is based on business, economic, oil and gas market, and
other conditions as of the date of our analysis and addresses the Merger Value
in the context of information available as of the date of our analysis. Events
occurring after that date could affect the value of the assets of the
Partnerships or the assumptions used in preparing this opinion.

         Based upon and subject to the foregoing, it is our opinion that, as of
the date of this letter and subject to the assumptions, limitations and
qualifications contained herein, the Merger Value ascribed to each Partnership
in connection with the Transaction and the allocation thereof to: (i) the
Limited Partners of each Partnership, as a group; (ii) the general partners of
each Partnership, as a group; (iii) Pioneer USA, as the managing or sole general
partner of each Partnership; (iv) the unaffiliated Limited Partners of each
Partnership, as a group; and (v) the unaffiliated limited partners of the
non-managing general partner of each applicable Partnership, as a group; is fair
to the unaffiliated Limited Partners of each Partnership and the unaffiliated
limited partners of the non-managing general partner of each applicable
Partnership, from a financial point of view.


Yours truly,


Robert A. Stanger & Co., Inc.
Shrewsbury, New Jersey
       , 2001



                                      D-5
   140

                                                                       EXHIBIT I

                                  PARTNERSHIPS


Parker & Parsley 81-I, Ltd.
Parker & Parsley 81-II, Ltd.
Parker & Parsley 82-I, Ltd.
Parker & Parsley 82-II, Ltd.
Parker & Parsley 82-III, Ltd.
Parker & Parsley 83-A, Ltd.
Parker & Parsley 83-B, Ltd.
Parker & Parsley 84-A, Ltd.
Parker & Parsley 85-A, Ltd.
Parker & Parsley 85-B, Ltd.
Parker & Parsley Private Investment 85-A, Ltd.
Parker& Parsley Selected 85 Private Investment, Ltd.
Parker & Parsley 86-A, Ltd.
Parker & Parsley 86-B, Ltd.
Parker & Parsley 86-C, Ltd.
Parker & Parsley Private Investment 86, Ltd.
Parker & Parsley 87-A Conv., Ltd.
Parker & Parsley 87-A, Ltd.
Parker & Parsley 87-B Conv., Ltd.
Parker & Parsley 87-B, Ltd.
Parker & Parsley Producing Properties 87-A, Ltd.
Parker & Parsley Producing Properties 87-B, Ltd.
Parker & Parsley Private Investment 87, Ltd.
Parker & Parsley 88-A Conv., Ltd.
Parker & Parsley 88-A, L.P.
Parker & Parsley 88-B Conv., L.P.
Parker & Parsley 88-B, L.P.
Parker & Parsley 88-C Conv., L.P.
Parker & Parsley 88-C, L.P.
Parker & Parsley Producing Properties 88-A, L.P.
Parker & Parsley Private Investment 88, L.P.
Parker & Parsley 89-A Conv., L.P.
Parker & Parsley 89-A, L.P.
Parker & Parsley 89-B Conv., L.P.
Parker & Parsley 89-B, L.P.
Parker & Parsley Private Investment 89, L.P.
Parker & Parsley 90-A Conv., L.P.
Parker & Parsley 90-A, L.P.
Parker & Parsley 90-B Conv., L.P.
Parker & Parsley 90-B, L.P.
Parker & Parsley 90-C Conv., L.P.
Parker & Parsley 90-C, L.P.
Parker & Parsley Private Investment 90, L.P.
Parker & Parsley 90 Spraberry Private Development, L.P.
Parker & Parsley 91-A, L.P.
Parker & Parsley 91-B, L.P.




                                      D-6
   141

                                   APPENDIX E

                                       TO

                           PROXY STATEMENT/PROSPECTUS


                              THE MERGER PROPOSALS

     The merger proposals for each partnership, except as otherwise indicated,
are set forth below. For each partnership, the merger proposals include the
approval of:

     o   the merger agreement for that partnership, pursuant to which:

         --   the partnership will be merged with and into Pioneer USA, on the
              terms and subject to the conditions set forth in the merger
              agreement as described in the proxy statement/prospectus; and


         --   each partner, whether limited or general, but other than Pioneer
              USA, will receive Pioneer Parent common stock in an amount based
              on the merger value of that partnership in exchange for that
              partner's partnership interests;


     o   the merger amendment for that partnership authorizing:

         --   the merger of the partnership with and into Pioneer USA, with
              Pioneer USA being the surviving entity; and

         --   the elimination of any restrictions on the merger otherwise
              contained in the partnership's partnership agreement; and

     o   the opinion of special legal counsel for the limited partners and the
         selection of that counsel.


     For each partnership, approval of the merger proposals requires the
affirmative vote of limited partners who own or have the power to vote a
majority, or 66-2/3% for Parker & Parsley 91-A, L.P. and Parker & Parsley 91-B,
L.P., of the limited partnership interests in that partnership. The effect of an
abstention or a failure to vote is the same as a vote against the merger
proposals. See "The Special Meetings -- Record Date; Voting Rights and Proxies."
Subject to the terms and conditions of the merger of each partnership as
described in the proxy statement/prospectus under "The Merger Agreement," if the
merger proposals are approved by a partnership, that participating partnership
will merge with and into Pioneer USA, with Pioneer USA being the surviving
entity. From and after the closing of the merger of each participating
partnership, the partnership interests of the partners in that partnership will
represent the right to receive an amount of Pioneer Parent common stock as
described in the proxy statement/prospectus.


     Generally, the partnership agreement of each partnership requires that
special legal counsel for the limited partners, acceptable to the partnership,
deliver a legal opinion, acceptable to the partnership, that (1) neither the
grant nor the exercise of the right to approve the merger of the partnership by
its limited partners will adversely affect the federal income tax classification
of the partnership or any of its limited partners and (2) neither the grant nor
exercise of such right will result in the loss of any limited partner's limited
liability. of Dallas, Texas has delivered that opinion, subject to the approval
of the limited partners of that opinion and the selection of special legal
counsel for the limited partners. See "The Merger of Each Partnership -- Legal
Opinion for Limited Partners."

APPROVAL OF MERGER FOR EACH PARTNERSHIP FORMED IN TEXAS:


     RESOLVED: That, subject to receipt of a favorable opinion of special legal
counsel for the limited partners as described in the proxy statement/prospectus,
the partnership be merged with and into Pioneer USA, with Pioneer USA being the
surviving entity, and that an amount of Pioneer Parent common stock be issued to
each partner, other than Pioneer USA, in accordance with the terms set forth in
the merger agreement included as Appendix F to the proxy statement/prospectus
and subject to the conditions set forth therein.




                                       E-1
   142

     RESOLVED: That, subject to receipt of a favorable opinion of special legal
counsel for the limited partners as described in the proxy statement/prospectus,
the following new article shall be added to the partnership agreement of the
partnership:

                                     ARTICLE

                      Notwithstanding any provisions of this Agreement to the
                  contrary, it is hereby agreed as follows:


                      1. Definitions. For the purposes of this Article, "Proxy
                  Statement/Prospectus" means the proxy statement/prospectus
                  dated , 2001 of Pioneer Natural Resources Company, a Delaware
                  corporation ("Pioneer Parent"), and Pioneer Natural Resources
                  USA, Inc., a Delaware corporation ("Pioneer USA"), contained
                  in the Registration Statement on Form S-4 (File No. 333-59094)
                  of Pioneer Parent filed with the Securities and Exchange
                  Commission.


                      2. Elimination of Restrictions to Transaction.
                  Notwithstanding anything in this Agreement to the contrary,
                  upon the consent of limited partners holding a majority of the
                  outstanding limited partnership interests in the partnership,
                  which consent may or may not be the same consent to the
                  adoption of an amendment to this Agreement, no provision of
                  this Agreement shall prohibit, limit or prevent:

                           (a) the merger or consolidation of the partnership,
                      including the merger described in the Proxy
                      Statement/Prospectus, with any other domestic limited
                      partnership or other entity, as those terms are defined in
                      the Texas Revised Limited Partnership Act, and

                           (b) the consummation of the merger of the partnership
                      as described in the Proxy Statement/Prospectus.

                  In addition, no consent of the partnership, Pioneer USA or any
                  partner or other procedure, including the delivery of opinions
                  of counsel, shall be required in order to enable the
                  partnership, Pioneer USA or any partner to effect the merger.

                      3. Mergers. For purposes of this Agreement, each merger
                  described in the Proxy Statement/Prospectus shall be treated
                  as if the partnership has:


                           (a) disposed of all of its assets and liabilities to
                      Pioneer USA in exchange for an amount of Pioneer Parent
                      common stock representing the merger value of the
                      partnership, and


                           (b) liquidated in the manner provided in the
                      liquidation provisions of this Agreement.


                  Accordingly, upon the partnership's deemed liquidation
                  resulting from the merger, Pioneer Parent will issue an amount
                  of Pioneer Parent common stock to the partners, other than
                  Pioneer USA, in accordance with the liquidation provisions of
                  this Agreement. For purposes of Texas law, the merger shall be
                  a merger subject to the provisions of Section 2.11 of the
                  Texas Revised Limited Partnership Act.


                      4. Authority of Pioneer USA as General Partner. By
                  obtaining the approval of the limited partners described in
                  Section 2 of this Article, the partnership hereby extends the
                  power of attorney granted to Pioneer USA pursuant to this
                  Agreement to permit Pioneer USA to execute the merger
                  agreement described in the Proxy Statement/Prospectus and the
                  merger amendment contemplated by this Article on behalf of the
                  limited partners. Pioneer USA shall be authorized, at such
                  time in its full discretion as it deems appropriate, to
                  execute, acknowledge, verify, deliver, file and record, for
                  and in the name and on behalf of the partnership, Pioneer USA
                  and the limited partners, any and all documents, agreements,
                  certificates and instruments, and shall do and perform any and
                  all acts required by applicable law or which Pioneer USA deems
                  necessary or advisable in order to give effect to this Article
                  and the transactions contemplated herein, including, but not
                  limited to, the merger.


                                      E-2
   143
                      5. This Article Controlling. The provisions of this
                  Article shall control over all other provisions of this
                  Agreement.

                  Except as herein expressly amended, all other terms and
                  provisions of this Agreement shall remain in full force and
                  effect.


APPROVAL OF MERGER FOR EACH PARTNERSHIP FORMED IN DELAWARE:


     RESOLVED: That, subject to receipt of a favorable opinion of special legal
counsel for the limited partners as described in the proxy statement/prospectus,
the partnership be merged with and into Pioneer USA, with Pioneer USA being the
surviving entity, and that an amount of Pioneer Parent common stock be issued to
each partner, other than Pioneer USA, in accordance with the terms set forth in
the merger agreement included as Appendix F to the proxy statement/prospectus
and subject to the conditions set forth therein.


     RESOLVED: That, subject to receipt of a favorable opinion of special legal
counsel for the limited partners as described in the proxy statement/prospectus,
the following new article shall be added to the partnership agreement of the
partnership:

                                     ARTICLE

                      Notwithstanding any provisions of this Agreement to the
                  contrary, it is hereby agreed as follows:


                      1. Definitions. For the purposes of this Article, "Proxy
                  Statement/Prospectus" means the proxy statement/prospectus
                  dated , 2001 of Pioneer Natural Resources Company, a Delaware
                  corporation ("Pioneer Parent"), and Pioneer Natural Resources
                  USA, Inc., a Delaware corporation ("Pioneer USA"), contained
                  in the Registration Statement on Form S-4 (File No. 333-59094)
                  of Pioneer Parent filed with the Securities and Exchange
                  Commission.


                      2. Elimination of Restrictions to Transaction.
                  Notwithstanding anything in this Agreement to the contrary,
                  upon the consent of limited partners holding a majority of the
                  outstanding limited partnership interests in the partnership,
                  which consent may or may not be the same consent to the
                  adoption of an amendment to this Agreement, no provision of
                  this Agreement shall prohibit, limit or prevent:

                           (a) the merger or consolidation of the partnership,
                      including the merger described in the Proxy
                      Statement/Prospectus, with any other domestic limited
                      partnership or other business entity, as those terms are
                      defined in the Delaware Revised Uniform Limited
                      Partnership Act, and

                           (b) the consummation of the merger of the partnership
                      as described in the Proxy Statement/Prospectus.

                  In addition, no consent of the partnership, Pioneer USA or any
                  partner or other procedure, including the delivery of opinions
                  of counsel, shall be required in order to enable the
                  partnership, Pioneer USA or any partner to effect the merger.

                      3. Mergers. For purposes of this Agreement, each merger
                  described in the Proxy Statement/Prospectus shall be treated
                  as if the partnership has:


                           (a) disposed of all of its assets and liabilities to
                      Pioneer USA in exchange for an amount of Pioneer Parent
                      common stock representing the merger value of the
                      partnership, and


                           (b) liquidated in the manner provided in the
                      liquidation provisions of this Agreement.



                                      E-3
   144

                  Accordingly, upon the partnership's deemed liquidation
                  resulting from the merger, Pioneer Parent will issue an amount
                  of Pioneer Parent common stock to the partners, other than
                  Pioneer USA, in accordance with the liquidation provisions of
                  this Agreement. For purposes of Delaware law, the merger shall
                  be a merger subject to the provisions of Section 17.11 of the
                  Delaware Revised Uniform Limited Partnership Act.


                      4. Authority of Pioneer USA as General Partner. By
                  obtaining the approval of the limited partners described in
                  Section 2 of this Article, the partnership hereby extends the
                  power of attorney granted to Pioneer USA pursuant to this
                  Agreement to permit Pioneer USA to execute the merger
                  agreement described in the Proxy Statement/Prospectus and the
                  merger amendment contemplated by this Article on behalf of the
                  limited partners. Pioneer USA shall be authorized, at such
                  time in its full discretion as it deems appropriate, to
                  execute, acknowledge, verify, deliver, file and record, for
                  and in the name and on behalf of the partnership, Pioneer USA
                  and the limited partners, any and all documents, agreements,
                  certificates and instruments, and shall do and perform any and
                  all acts required by applicable law or which Pioneer USA deems
                  necessary or advisable in order to give effect to this Article
                  and the transactions contemplated herein, including, but not
                  limited to, the merger.

                      5. This Article Controlling. The provisions of this
                  Article shall control over all other provisions of this
                  Agreement.

                  Except as herein expressly amended, all other terms and
                  provisions of this Agreement shall remain in full force and
                  effect.

APPROVAL OF COUNSEL TO LIMITED PARTNERS FOR EACH PARTNERSHIP:

     RESOLVED: That the selection of of Dallas, Texas as special legal counsel
for the limited partners of the partnership for the purpose of rendering the
legal opinion described in the proxy statement/prospectus under "The Merger of
Each Partnership -- Legal Opinion for Limited Partners" be and hereby is
approved by Pioneer USA, on behalf of the partnership, and the limited partners
of such partnership.

     RESOLVED: That the legal opinion delivered pursuant to the partnership
agreement of the partnership as described in the proxy statement/prospectus
under "The Merger of Each Partnership -- Legal Opinion for Limited Partners," in
form and substance as set forth in Exhibit A to these merger proposals, be and
hereby is approved as in form and substance satisfactory to the limited partners
of such partnership in their reasonable judgment.




                                      E-4
   145
                                    EXHIBIT A


                                  TO APPENDIX E


                                       TO

                           PROXY STATEMENT/PROSPECTUS

                                   OPINION OF



Pioneer Natural Resources USA, Inc.,
As Sole or Managing General Partner of
46 Limited Partnerships Named in the
Proxy Statement/Prospectus dated             , 2001
1400 Williams Square West
5205 North O'Connor Blvd.
Irving, Texas 75039

     We are of the opinion that (1) neither the grant nor the exercise of the
right to approve the merger of each partnership with and into Pioneer Natural
Resources USA, Inc. by the partnership's limited partners will adversely affect
the federal income tax classification of the partnership or any of its limited
partners and (2) neither the grant nor exercise of such right will result in the
loss of any limited partner's limited liability.


     We hereby consent to the references to our firm and this opinion contained
in the proxy statement/prospectus forming a part of the registration statement
on Form S-4 (File No. 333-59094) filed with the Securities and Exchange
Commission by Pioneer Natural Resources Company, a Delaware corporation, in
connection with the merger of each of the limited partnerships with and into
Pioneer Natural Resources USA, Inc., a Delaware corporation.






                                      E-5
   146

                                   APPENDIX F

                                       TO

                           PROXY STATEMENT/PROSPECTUS


                                     FORM OF

                          AGREEMENT AND PLAN OF MERGER
                           (DRILLING AND INCOME FUNDS)


         THIS AGREEMENT AND PLAN OF MERGER dated as of      , 2001 (this "Merger
Agreement"), is entered into by and among Pioneer Natural Resources Company, a
Delaware corporation ("Pioneer Parent"), Pioneer Natural Resources USA, Inc., a
Delaware corporation and wholly-owned subsidiary of Pioneer Parent ("Pioneer
USA"), and each of the limited partnerships referred to below (each, a
"Partnership" and collectively, the "Partnerships").


                                    RECITALS

         A.   Pioneer USA is the sole or managing general partner of each of the
following Partnerships:



                                                                     STATE OF
                       PARTNERSHIP NAME                             FORMATION
---------------------------------------------------------------  -----------------
                                                              
Parker & Parsley 81-I, Ltd.                                           Texas
Parker & Parsley 81-II, Ltd.                                          Texas
Parker & Parsley 82-I, Ltd.                                           Texas
Parker & Parsley 82-II, Ltd.                                          Texas
Parker & Parsley 82-III, Ltd.                                         Texas
Parker & Parsley 83-A, Ltd.                                           Texas
Parker & Parsley 83-B, Ltd.                                           Texas
Parker & Parsley 84-A, Ltd.                                           Texas
Parker & Parsley 85-A, Ltd.                                           Texas
Parker & Parsley 85-B, Ltd.                                           Texas
Parker & Parsley Private Investment 85-A, Ltd.                        Texas
Parker & Parsley Selected 85 Private Investment, Ltd.                 Texas
Parker & Parsley 86-A, Ltd.                                           Texas
Parker & Parsley 86-B, Ltd.                                           Texas
Parker & Parsley 86-C, Ltd.                                           Texas
Parker & Parsley Private Investment 86, Ltd.                          Texas
Parker & Parsley 87-A Conv., Ltd.                                     Texas
Parker & Parsley 87-A , Ltd.                                          Texas
Parker & Parsley 87-B Conv., Ltd.                                     Texas
Parker & Parsley 87-B, Ltd.                                           Texas
Parker & Parsley Producing Properties 87-A, Ltd.                      Texas
Parker & Parsley Producing Properties 87-B, Ltd.                      Texas
Parker & Parsley Private Investment 87, Ltd.                          Texas
Parker & Parsley 88-A Conv., L.P.                                    Delaware
Parker & Parsley 88-A, L.P.                                          Delaware
Parker & Parsley 88-B Conv., L.P.                                    Delaware
Parker & Parsley 88-B, L.P.                                          Delaware
Parker & Parsley 88-C Conv., L.P.                                    Delaware
Parker & Parsley 88-C, L.P.                                          Delaware
Parker & Parsley Producing Properties 88-A, L.P.                     Delaware
Parker & Parsley Private Investment 88, L.P.                         Delaware
Parker & Parsley 89-A Conv., L.P.                                    Delaware
Parker & Parsley 89-A, L.P.                                          Delaware
Parker & Parsley 89-B Conv., L.P.                                    Delaware



                                      F-1
   147



                                                                     STATE OF
                       PARTNERSHIP NAME                             FORMATION
---------------------------------------------------------------  -----------------
                                                              
Parker & Parsley 89-B, L.P.                                          Delaware
Parker & Parsley Private Investment 89, L.P.                         Delaware
Parker & Parsley 90-A Conv., L.P.                                    Delaware
Parker & Parsley 90-A, L.P.                                          Delaware
Parker & Parsley 90-B Conv., L.P.                                    Delaware
Parker & Parsley 90-B, L.P.                                          Delaware
Parker & Parsley 90-C Conv., L.P.                                    Delaware
Parker & Parsley 90-C, L.P.                                          Delaware
Parker & Parsley Private Investment 90, L.P.                         Delaware
Parker & Parsley 90 Spraberry Private Development, L.P.              Delaware
Parker & Parsley 91-A, L.P.                                          Delaware
Parker & Parsley 91-B, L.P.                                          Delaware



         B. Each of P&P Employees 81-I, Ltd., a Texas limited partnership, P&P
Employees 81-II, Ltd., a Texas limited partnership, P&P Employees 82-I, Ltd., a
Texas limited partnership, P&P Employees 82-II, Ltd., a Texas limited
partnership, P&P Employees 82-III, Ltd., a Texas limited partnership, P&P
Employees 83-A, Ltd., a Texas limited partnership, P&P Employees 83-B, Ltd., a
Texas limited partnership, and P&P Employees 84-A, Ltd., a Texas limited
partnership (individually, the "Nonmanaging General Partner" and collectively,
the "Nonmanaging General Partners"), is the nonmanaging general partner of
Parker & Parsley 81-I, Ltd., Parker & Parsley 81-II, Ltd., Parker & Parsley
82-I, Ltd., Parker & Parsley 82-II, Ltd., Parker & Parsley 82-III, Ltd., Parker
& Parsley 83-A, Ltd. Parker & Parsley 83-B, Ltd. and Parker & Parsley 84-A,
Ltd., respectively.


         C. Pioneer USA is the sole general partner of each of the Nonmanaging
General Partners and in such capacity has authority (i) to cause the Nonmanaging
General Partner to perform its obligations under the partnership agreement of
the respective Partnership; and (ii) to exercise on behalf of the Nonmanaging
General Partner all of the rights and elections granted to such Nonmanaging
General Partner by the respective Partnership.

         D. The board of directors of each of Pioneer Parent and Pioneer USA has
determined that it is in the best interests of Pioneer Parent and Pioneer USA
(in its individual capacity, as the sole or managing general partner of each
Partnership and as the sole general partner of each Nonmanaging General Partner)
to merge each Partnership with and into Pioneer USA and each such board of
directors has approved the merger of each Partnership referred to below, upon
the terms and subject to the conditions contained herein.


         E. Pioneer USA intends to solicit the vote of the limited partners of
each Partnership holding at least a majority (or with respect to Parker &
Parsley 91-A, L.P. and Parker & Parsley 91-B, L.P. (each, a "Super-Majority
Partnership"), at least 66-2/3%) of the outstanding limited partnership
interests of the Partnership to approve the merger of the Partnership. Subject
to certain limitations, upon consummation of the merger of each Partnership, the
partners, other than Pioneer USA, will have the right to receive a number of
shares of common stock, par value $0.01 per share, of Pioneer Parent (the
"Pioneer Parent Common Stock").


                                   AGREEMENTS

         NOW, THEREFORE, in consideration of the premises and the mutual
agreements contained herein, the parties hereto agree as follows:

                                    ARTICLE 1
                         THE MERGER OF EACH PARTNERSHIP

         1.1 Merger of Each Partnership. At the Effective Time (as defined in
Section 1.4), each Partnership shall be merged with and into Pioneer USA, the
separate existence of the Partnership shall cease, and Pioneer USA, as the
surviving corporation, shall continue to exist by virtue of and shall be
governed by the laws of the State of Delaware.



                                      F-2
   148


         1.2  Merger Value for Each Partnership; Pioneer Parent Common Stock
Offered.

                  (a) At the Effective Time, by virtue of the merger of each
Partnership and without any action on the part of Pioneer USA or the other
partners of the Partnership, each partnership interest outstanding immediately
prior thereto shall be converted into the right to receive an amount of Pioneer
Parent Common Stock allocated to the Partnership, which amount shall be
determined in accordance with the merger value assigned to the Partnership
pursuant to the procedures set forth herein and in the Proxy
Statement/Prospectus (as defined in Section 4.3) and the procedures set forth in
the Partnership's partnership agreement for allocating liquidation distributions
as though the assets of the Partnership were sold for the merger value of the
Partnership. The merger value for each Partnership is equal to the sum of the
present value of estimated future net revenues from the Partnership's estimated
oil and gas reserves and its net working capital, in each case as of March 31,
2001 and determined as described in the Proxy Statement/Prospectus, less its pro
rata share, based on its reserve value, of the estimated expenses and fees of
the mergers of all of the Partnerships and less the cash distribution to be
mailed on or about July 12, 2001, by the Partnership to its partners. The merger
value for each Partnership will not be adjusted as of the Closing Date. The
number of shares of Pioneer Parent Common Stock to be issued for each
partnership interest of each Partnership will be based on (i) the Partnership's
merger value divided by (ii) the average closing price of the Pioneer Parent
Common Stock, as reported by the New York Stock Exchange, for the ten trading
days ending three business days before the initial date of the special meeting
for the Partnership. For purposes of illustration in the Proxy
Statement/Prospectus, Pioneer Parent and Pioneer USA calculated the aggregate
number of shares of Pioneer Parent Common Stock to be offered based on $18.00
per share of Pioneer Parent Common Stock. Pioneer Parent and Pioneer USA shall
update the aggregate number of shares of Pioneer Parent Common Stock to be
issued based on the average closing price as described in clause (ii) above
before the date of the special meeting for each Partnership. The merger value
assigned to each Partnership and the amount of Pioneer Parent Common Stock
offered with respect to each $1,000 investment by the limited partners in the
Partnership pursuant to the merger of the Partnership are set forth in the table
entitled "Summary Table - Merger Value and Amount of Initial Limited Partner
Investment Repaid" in the Proxy Statement/Prospectus.

                  (b) All partnership interests of each Partnership, when
converted into the right to receive Pioneer Parent Common Stock, shall no longer
be outstanding and shall automatically be cancelled and retired and shall cease
to exist, and each holder of a certificate representing any such partnership
interests shall cease to have any rights with respect thereto, except the right
to receive the amount of Pioneer Parent Common Stock to be delivered in
consideration therefor.


                  (c) The partnership interests, whether general or limited, in
each Partnership held directly or indirectly by Pioneer USA shall be cancelled
without any consideration being received therefor; provided, however, that as a
result of the merger of each Partnership, Pioneer USA will own 100% of the
properties of the Partnership, including properties attributable to its
partnership interests in the Partnership.


                  (d) No fractional shares of Pioneer Parent Common Stock will
be issued. Each fractional share of Pioneer Parent Common Stock to be issued to
a partner of a Partnership will be rounded up to the nearest whole share.

                  (e) When any person has partnership interests in more than one
Partnership that merges with Pioneer USA, Pioneer USA and Pioneer Parent may, at
their sole discretion, aggregate the number of shares of Pioneer Parent Common
Stock to be issued to that person before making the rounding and other
adjustments provided in the preceding clause (d).

                  (f) If any limited partner is indebted to Pioneer USA for any
portion of the limited partner's original investment in the Partnership, Pioneer
USA plans to apply the Pioneer Parent Common Stock that would otherwise be
distributed to the limited partner upon completion of the merger of the
Partnership against that limited partner's indebtedness. If a limited partner's
indebtedness to Pioneer USA is less than the merger value allocated to limited
partnership interests held by the limited partner, the limited partner shall
receive Pioneer Parent Common Stock equal to the amount by which such merger
value exceeds such indebtedness. If a limited partner's indebtedness to Pioneer
USA is greater than the merger value allocated to the limited partnership
interests held by the limited partner, Pioneer USA may collect the deficiency
from the limited partner.




                                      F-3
   149

                  (g) To the extent that Pioneer USA or a Partnership is
required to withhold and pay over, or otherwise pay, any withholding or other
tax (the "Required Withholding") with respect to a partner or former partner in
a Partnership (the "Withholding Partner") as a result of the Withholding
Partner's current or former participation in the Partnership, Pioneer USA or the
Partnership shall be entitled to deduct and withhold (or cause to be deducted
and withheld) the Required Holding from the merger consideration (including the
Pioneer Parent Common Stock) otherwise payable to the Withholding Partner. In
the event Pioneer USA or a Partnership withholds Pioneer Parent Common Stock in
order to satisfy the Required Withholding with respect to a Withholding Partner,
Pioneer USA or the Partnership, as appropriate, may, in its sole discretion, (i)
sell such Pioneer Parent Common Stock and use the proceeds therefrom to satisfy
the Required Withholding, (ii) hold such Pioneer Parent Common Stock as security
for the satisfaction of the Required Withholding by the Withholding Partner, in
which case the Pioneer Parent Common Stock shall be released to the Withholding
Partner upon the full satisfaction of the Required Withholding by the
Withholding Partner, or (iii) take such other reasonable action as is required
or appropriate to satisfy the Required Withholding at the sole expense of the
Withholding Partner. To the extent that amounts are so withheld or deducted (or
caused to be withheld or deducted) by Pioneer USA or a Partnership, such amounts
shall be treated for all purposes of this Merger Agreement as having been paid
to the Withholding Partner.


         1.3 Closing. The closing of the merger of each Partnership (the
"Closing") shall take place at the offices of Vinson & Elkins L.L.P., 3700
Trammell Crow Center, 2001 Ross Avenue, Dallas, Texas 75201, as soon as
practicable after the fulfillment of the conditions referred to in Article 4, or
at such other time and place as the parties shall agree (the date of such
Closing being the "Closing Date").

         1.4 Effective Time of Merger of Each Partnership. Upon satisfaction of
the conditions set forth in Article 4 hereof and as soon as practicable after
the Closing, this Merger Agreement, or a certificate of merger setting forth the
information required by, and otherwise in compliance with, Section 263 of the
General Corporation Law of the State of Delaware (the "DGCL") and, if
applicable, Section 17-211 of the Revised Uniform Limited Partnership Act of the
State of Delaware (the "DRULPA") with respect to the merger of each Partnership,
shall be delivered for filing with the Secretary of State of the State of
Delaware. At such time, if applicable, a certificate of merger with respect to
the merger of each Partnership setting forth the information required by, and
otherwise in compliance with, Section 2.11 the Revised Limited Partnership Act
of the State of Texas (the "TRLPA") shall be delivered for filing with the
Secretary of State of the State of Texas. The merger of each Partnership shall
become effective upon the later of (a) the day and at the time the Secretary of
State of the State of Delaware files this Merger Agreement or such certificate
of merger in compliance with Section 263 of the DGCL and, if applicable, Section
17-211 of the DRULPA, and (b) if applicable, the day and at the time the
Secretary of State of the State of Texas files such certificate of merger in
compliance with Section 2.11 of the TRLPA (the time of such effectiveness is
herein called the "Effective Time"). Notwithstanding the foregoing, by action of
its board of directors, either Pioneer Parent or Pioneer USA, in its individual
capacity or as the sole general partner of each Partnership, may terminate this
Merger Agreement at any time prior to the earlier of (a) the filing of this
Merger Agreement or the certificate of merger with respect to the merger of the
Partnership in compliance with Section 263 of the DGCL and, if applicable,
Section 17-211 of the DRULPA with the Secretary of State of the State of
Delaware and (b) if applicable, the filing of the certificate of merger with
respect to the merger of the Partnership in compliance with Section 2.11 of the
TRLPA with Secretary of State of the State of Texas.

         1.5 Effect of Merger of Each Partnership. At the Effective Time of the
merger of each Partnership, Pioneer USA, without further action, as provided by
the laws of the State of Delaware and the State of Texas, as the case may be,
shall succeed to and possess all the rights, privileges, powers, and franchises,
of a public as well as of a private nature, of the Partnership; and all
property, real, personal and mixed, and all debts due on whatsoever account,
including subscriptions to shares, and all other choses in action, and all and
every other interest, of or belonging to or due to the Partnership shall be
deemed to be vested in Pioneer USA without further act or deed; and the title to
any real estate, or any interest therein, vested in Pioneer USA or the
Partnership shall not revert or be in any way impaired by reason of the merger
of the Partnership. Such transfer to and vesting in Pioneer USA shall be deemed
to occur by operation of law, and no consent or approval of any other person
shall be required in connection with any such transfer or vesting unless such
consent or approval is specifically required in the event of merger or
consolidation by law or express provision in any contract, agreement, decree,
order, or other instrument to which Pioneer USA or the Partnership is a party or
by which either of them is bound. At and after the Effective Time, Pioneer USA
shall be responsible and liable for all debts, liabilities, and duties of each
Partnership, including franchise taxes, if any, which may be enforced against
Pioneer USA to the same extent as if said debts, liabilities,




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and duties had been incurred or contracted by it. Neither the rights of
creditors nor any liens upon the property of any Partnership or Pioneer USA
shall be impaired by the merger of any Partnership.

         1.6 Certificate of Incorporation and Bylaws. The certificate of
incorporation of Pioneer USA before the merger of each Partnership shall be and
remain the certificate of incorporation of Pioneer USA after the Effective Time,
until the same shall thereafter be altered, amended, or repealed in accordance
with law and Pioneer USA's certificate of incorporation. The bylaws of Pioneer
USA as in effect at the Effective Time shall be and remain the bylaws of Pioneer
USA, as the surviving corporation, until the same shall thereafter be altered,
amended, or repealed in accordance with law, Pioneer USA's certificate of
incorporation or such bylaws.

         1.7 Pioneer USA Common Stock. At the Effective Time, each outstanding
share of common stock of Pioneer USA shall remain outstanding and shall continue
to represent one share of common stock of Pioneer USA.

         1.8 Officers and Directors. At the Effective Time, each of the persons
who was serving as an officer of Pioneer USA immediately prior to the Effective
Time shall continue to be an officer of Pioneer USA and shall continue to serve
in such capacity at the pleasure of the board of directors of Pioneer USA or, if
earlier, until their respective death or resignation. At the Effective Time,
each of the persons who was serving as a director of Pioneer USA immediately
prior to the Effective Time shall continue to be a director of Pioneer USA, and
each shall serve in such capacity until the next annual meeting of stockholders
of Pioneer USA and until his or her successor is elected and qualified or, if
earlier, until his death, resignation, or removal from office.

         1.9  Exchange of Partnership Interests for Pioneer Parent Common Stock.


                  (a) Continental Stock Transfer & Trust Company shall act as
the transfer and exchange agent (in such capacity, the "Transfer Agent") in
connection with the issuance of certificates representing shares of Pioneer
Parent Common Stock pursuant to Section 1.2.

                  (b) The Transfer Agent shall mail certificates representing
shares of Pioneer Parent Common Stock to the partners of record, other than
Pioneer USA, of each Partnership promptly following the Closing Date in payment
of the merger consideration. Limited partners and Nonmanaging General Partners
of each Partnership will not be required to surrender partnership interest
certificates to receive the Pioneer Parent Common Stock.

                  (c) If any certificate representing shares of Pioneer Parent
Common Stock is to be issued in a name other than that in which the limited
partnership interests cancelled in exchange therefor are registered, it shall be
a condition of the issuance thereof that the person requesting such exchange
shall pay to the Transfer Agent any transfer or other taxes required by reason
of the issuance of a certificate representing shares of Pioneer Parent Common
Stock in any name other than that of the registered holder of the cancelled
limited partnership interests, or otherwise required, or shall establish to the
satisfaction of the Transfer Agent that such tax has been paid or is not
payable.

                  (d) After the Closing Date, there shall not be any further
registration of transfers on the transfer books of any Partnership of the
partnership interests that were issued and outstanding immediately before the
Closing Date and were converted into the right to receive Pioneer Parent Common
Stock. If, after the Closing Date, certificates representing partnership
interests of a Partnership are presented, they shall be exchanged for Pioneer
Parent Common Stock, all as provided in this Article.


                                    ARTICLE 2
                         REPRESENTATIONS AND WARRANTIES


         2.1 Representations and Warranties of Each Partnership. Each
Partnership hereby represents and warrants to Pioneer Parent and Pioneer USA as
follows:


                  (a) Formation; Qualification. The Partnership is a limited
partnership duly formed under the DRULPA or TRLPA, as applicable, and is validly
existing and in good standing under the laws of the State of Delaware or the
State of Texas, as applicable. The Partnership has all requisite partnership
power and authority to own, operate or lease its properties and to carry on its
business as now being conducted. The Partnership is duly qualified to do
business as a foreign limited partnership and is in good standing in each
jurisdiction where the



                                      F-5
   151

character of its properties owned, operated or leased, or the nature of its
activities, makes such qualifications necessary.

                  (b) Capitalization. All of the outstanding partnership
interests of the Partnership are free of all liens, encumbrances, defects and
preemptive rights and are fully paid. Except as described in the Proxy
Statement/Prospectus, there are no outstanding subscriptions, options or other
arrangements or commitments obligating the Partnership to issue any additional
partnership interests.

                  (c) No Conflicts. Assuming this Merger Agreement is approved
by the requisite vote of the limited partners of the Partnership (with respect
to Parker & Parsley 85-A, Ltd., Parker & Parsley 85-B, Ltd., Parker & Parsley
Private Investment 85-A, Ltd., Parker & Parsley Selected 85 Private Investment,
Ltd., Parker & Parsley Private Investment 86, Ltd., Parker & Parsley 91-A, L.P.
and Parker & Parsley 91-B, L.P. (each, a "Special Vote Partnership"), excluding
Pioneer USA and its affiliates), consummation of the transactions contemplated
hereby and compliance with the terms and provisions of this Merger Agreement
will not conflict with, result in a breach of, require notice under or
constitute a default under (i) its certificate of limited partnership or
partnership agreement, (ii) any material judgment, order, injunction, decree or
ruling of any court or governmental authority or (iii) any material agreement,
indenture or instrument to which the Partnership is a party.

                  (d) Authority, Authorization and Enforceability. The
Partnership has all requisite power and authority to enter into and perform the
provisions of this Merger Agreement. The execution and delivery of this Merger
Agreement and the consummation of the transactions contemplated hereby have been
duly authorized by all necessary partnership action on the part of the
Partnership other than the approval of its limited partners (with respect to
each Special Vote Partnership, excluding Pioneer USA and its affiliates).
Subject to such approval, this Merger Agreement has been duly executed and
delivered by the Partnership and constitutes a valid and binding obligation of
the Partnership enforceable in accordance with its terms.

                  (e) SEC Reports; Financial Statements.

                           (i) With respect to each of Reporting Partnership (as
         defined below), the Partnership's (A) Annual Report on Form 10-K for
         the year ended December 31, 2000, (B) Quarterly Report on Form 10-Q for
         the quarter ended March 31, 2001, and (C) all other reports or
         registration statements filed with the Securities and Exchange
         Commission (the "SEC") since December 31, 2000 (collectively, the
         "Partnership's SEC Reports") (1) were prepared in accordance with the
         applicable requirements of the Securities Act of 1933 (the "Securities
         Act") and the Securities Exchange Act of 1934 (the "Exchange Act"), and
         (2) as of their respective dates, did not contain any untrue statement
         of a material fact or omit to state a material fact required to be
         stated therein or necessary in order to make the statements therein, in
         the light of the circumstances under which they are made, not
         misleading.

                           (ii) Each of the financial statements of the
         Partnership for the year ended December 31, 2000 and for the three
         months ended March 31, 2001 contained in the Partnership's supplement
         to the Proxy Statement/Prospectus and, with respect to each Reporting
         Partnership, in the Partnership's SEC Reports has been prepared in
         accordance with generally accepted accounting principles applied on a
         consistent basis throughout the periods involved (except as may be
         indicated in the notes thereto) and each fairly presents the financial
         position of the Partnership as of the respective dates thereof and the
         results of operations and cash flows of the Partnership for the periods
         indicated, except that the unaudited interim financial statements are
         subject to normal and recurring year-end adjustments that are not
         expected to be material in amount.

                           (iii) For purposes hereof, the term "Reporting
         Partnership" means: Parker & Parsley 82-I, Ltd., Parker & Parsley
         82-II, Ltd., Parker & Parsley 83-A, Ltd., Parker & Parsley 83-B, Ltd.,
         Parker & Parsley 84-A, Ltd., Parker & Parsley 85-A, Ltd., Parker &
         Parsley 85-B, Ltd., Parker & Parsley 86-A, Ltd., Parker & Parsley 86-B,
         Ltd., Parker & Parsley 86-C, Ltd., Parker & Parsley 87-A, Ltd., Parker
         & Parsley 87-B, Ltd., Parker & Parsley Producing Properties 87-A, Ltd.,
         Parker & Parsley Producing Properties 87-B, Ltd., Parker & Parsley
         88-A, L.P., Parker & Parsley 88-B, L.P., Parker & Parsley Producing
         Properties 88-A, L.P., Parker & Parsley 89-A, L.P., Parker & Parsley
         90-A L.P., Parker & Parsley 90-B Conv., L.P., Parker & Parsley 90-B,
         L.P., Parker & Parsley 90-C Conv., L.P., Parker & Parsley 90-C, L.P.,
         Parker & Parsley 91-A, L.P. and Parker & Parsley 91-B, L.P.


                                      F-6
   152

                  (f) No Material Adverse Change. Since March 31, 2001, the
Partnership has conducted its operations in the ordinary and usual course of
business and has paid all of its obligations as they have become due; and the
business of the Partnership has not undergone any material adverse change since
such date.

                  (g) Accuracy of Information. None of the information supplied
or to be supplied by the Partnership for inclusion in the Proxy
Statement/Prospectus, as amended or supplemented, will, at the time of the
mailing of the Proxy Statement/Prospectus, the time of the special meeting of
the limited partners of the Partnership (each, a "Special Meeting") or the
Closing Date, be false or misleading with respect to any material fact, contain
any untrue statement of material fact or omit to state any material fact
required to be stated therein or necessary in order to make the statements
therein, in the light of the circumstances under which they were made, not
misleading.


         2.2 Representations and Warranties of Pioneer USA. Pioneer USA hereby
represents and warrants to Pioneer Parent and each Partnership as follows:


                  (a) Organization; Qualification. Pioneer USA is a corporation
duly formed under the DGCL and is validly existing and in good standing under
the laws of the State of Delaware. Pioneer USA has all requisite corporate power
and authority to own, operate or lease its properties and to carry on its
business as now being conducted. Pioneer USA is duly qualified to do business as
a foreign corporation and is in good standing in each jurisdiction where the
character of its properties owned, operated or leased, or the nature of its
activities, makes such qualifications necessary.

                  (b) No Conflicts. Consummation of the transactions
contemplated hereby and compliance with the terms and provisions of this Merger
Agreement will not conflict with, result in a breach of, require notice under or
constitute a default under (i) its certificate of incorporation or bylaws, (ii)
any material judgment, order, injunction, decree or ruling of any court or
governmental authority or (iii) any material agreement, indenture or instrument
to which Pioneer USA is a party.

                  (c) Authority, Authorization and Enforceability. Pioneer USA
has all requisite corporate power and authority to execute and deliver this
Merger Agreement and to perform the provisions of this Merger Agreement. The
execution and delivery of this Merger Agreement and the consummation of the
transactions contemplated hereby have been duly authorized by all necessary
corporate action on the part of Pioneer USA. This Merger Agreement has been duly
executed and delivered by Pioneer USA and constitutes a valid and binding
obligation of Pioneer USA enforceable in accordance with its terms.

                  (d) No Material Adverse Change. Since March 31, 2001, Pioneer
USA has conducted its operations in the ordinary and usual course of business
and has paid all of its obligations as they have become due; and the business of
Pioneer USA has not undergone any material adverse change since such date.

                  (e) Accuracy of Information. None of the information supplied
or to be supplied by Pioneer USA for inclusion in the Proxy
Statement/Prospectus, as amended or supplemented, will, at the time of the
mailing of the Proxy Statement/Prospectus, the time of the Special Meeting of
each Partnership or the Closing Date, be false or misleading with respect to any
material fact, contain any untrue statement of material fact or omit to state
any material fact required to be stated therein or necessary in order to make
the statements therein, in the light of the circumstances under which they were
made, not misleading.

                  (f) Capacity as General Partner. Pioneer USA is the sole or
managing general partner of each Partnership and is the sole general partner of
each Nonmanaging General Partner.


         2.3 Representations and Warranties of Pioneer Parent. Pioneer Parent
hereby represents and warrants to Pioneer USA and each Partnership as follows:

                  (a) Organization; Qualification. Pioneer Parent is a
corporation duly formed under the DGCL and is validly existing and in good
standing under the laws of the State of Delaware. Pioneer Parent has all
requisite corporate power and authority to own, operate or lease its properties
and to carry on its business as now being conducted. Pioneer Parent is duly
qualified to do business as a foreign corporation and is in good standing in
each jurisdiction where the character of its properties owned, operated or
leased, or the nature of its activities, makes such qualifications necessary.




                                      F-7
   153


                  (b) No Conflicts. Consummation of the transactions
contemplated hereby and compliance with the terms and provisions of this Merger
Agreement will not conflict with, result in a breach of, require notice under or
constitute a default under (i) its certificate of incorporation or bylaws, (ii)
any material judgment, order, injunction, decree or ruling of any court or
governmental authority or (iii) any material agreement, indenture or instrument
to which Pioneer Parent is a party.

                  (c) Authority, Authorization and Enforceability. Pioneer
Parent has all requisite corporate power and authority to execute and deliver
this Merger Agreement and to perform the provisions of this Merger Agreement.
The execution and delivery of this Merger Agreement and the consummation of the
transactions contemplated hereby have been duly authorized by all necessary
corporate action on the part of Pioneer Parent. This Merger Agreement has been
duly executed and delivered by Pioneer Parent and constitutes a valid and
binding obligation of Pioneer Parent enforceable in accordance with its terms.
When issued in accordance with this Merger Agreement, the shares of Pioneer
Parent Common Stock will be validly issued, fully paid and nonassessable and not
subject to preemptive rights.


                  (d) SEC Reports; Financial Statements.


                           (i) Pioneer Parent's (A) Annual Report on Form 10-K
         for the year ended December 31, 2000, (B) Quarterly Report on Form 10-Q
         for the quarter ended March 31, 2001, and (C) all other reports or
         registration statements filed with the SEC since December 31, 2000
         (collectively, "Pioneer Parent's SEC Reports") (1) were prepared in
         accordance with the applicable requirements of the Securities Act and
         the Exchange Act, and (2) as of their respective dates, did not contain
         any untrue statement of a material fact or omit to state a material
         fact required to be stated therein or necessary in order to make the
         statements therein, in the light of the circumstances under which they
         are made, not misleading.

                           (ii)Each of the financial statements of Pioneer
         Parent for the year ended December 31, 2000 and for the three months
         ended March 31, 2001 contained in Pioneer Parent's SEC Reports has been
         prepared in accordance with generally accepted accounting principles
         applied on a consistent basis throughout the periods involved (except
         as may be indicated in the notes thereto) and each fairly presents the
         financial position of Pioneer Parent as of the respective dates thereof
         and the results of operations and cash flows of Pioneer Parent for the
         periods indicated, except that the unaudited interim financial
         statements are subject to normal and recurring year-end adjustments
         that are not expected to be material in amount.

                  (e) No Material Adverse Change. Since March 31, 2001, Pioneer
Parent has conducted its operations in the ordinary and usual course of business
and has paid all of its obligations as they have become due; and the business of
Pioneer Parent has not undergone any material adverse change since such date.


                  (f) Accuracy of Information. None of the information supplied
or to be supplied by Pioneer Parent for inclusion in the Proxy
Statement/Prospectus, as amended or supplemented, will, at the time of the
mailing of the Proxy Statement/Prospectus, the time of the Special Meeting of
each Partnership or the Closing Date, be false or misleading with respect to any
material fact, contain any untrue statement of material fact or omit to state
any material fact required to be stated therein or necessary in order to make
the statements therein, in the light of the circumstances under which they were
made, not misleading.

                                    ARTICLE 3
             CONDITIONS PRECEDENT TO THE MERGER OF EACH PARTNERSHIP

         3.1 Conditions to Each Party's Obligations to Effect the Merger of Each
Partnership. The respective obligations of each party to effect the merger of
each Partnership shall be subject to the fulfillment (or waiver in whole or in
part by the intended beneficiary thereof in its sole discretion) at or prior to
the Closing Date of the following conditions:

                  (a) This Merger Agreement, an amendment to the partnership
agreement of each Partnership to permit the merger of such Partnership (the
"Merger Amendment"), the selection of special counsel for the limited partners
and that counsel's legal opinion referred to in Section 3.1(c) shall have been
approved by the limited partners (with respect to each Special Vote Partnership,
excluding Pioneer USA and its affiliates) holding at least a



                                      F-8
   154
 majority (or, with respect to each Super-Majority Partnership, at least
66-2/3%) of the outstanding limited partnership interests voting in person or by
proxy at the Special Meetings at which a quorum is present, with respect to each
merger.

                  (b) Pioneer USA shall have received from Robert A. Stanger &
Co., Inc. a written opinion for inclusion in the Proxy Statement/Prospectus
satisfactory in form and substance to Pioneer USA and substantially to the
effect that, as of the date of that opinion, the merger value for each
Partnership and the allocation of the merger value of the Partnership (1) to the
limited partners of the Partnership as a group, (2) to the general partners of
the Partnership as a group, (3) to Pioneer USA as the managing or sole general
partner of the Partnership, (4) to the unaffiliated limited partners of the
Partnership as a group and (5) to the unaffiliated limited partners of the
Nonmanaging General Partner, if any, of the Partnership as a group, is fair to
the unaffiliated limited partners of the Partnership and the unaffiliated
limited partners of the Nonmanaging General Partner, if any, of the Partnership,
from a financial point of view. Such opinion shall not have been withdrawn prior
to the Closing Date, unless a replacement opinion or opinions of an investment
banking firm or firms satisfactory to Pioneer USA to a similar effect has been
received by Pioneer USA and has not been withdrawn.

                  (c) The receipt, on or prior to the Closing Date, by Pioneer
USA of the opinion of special legal counsel for the limited partners pursuant to
the partnership agreement of each Partnership.

                  (d) No provision of any applicable law or regulation and no
judgment, injunction, order or decree shall prohibit the consummation of the
merger of any Partnership and the transactions related thereto.


                  (e) No suit, action or proceeding shall have been filed or
otherwise be pending against Pioneer Parent, Pioneer USA or any officer,
director or affiliate of Pioneer Parent or Pioneer USA challenging the legality
or any aspect of the merger of any Partnership or the transactions related
thereto.

                  (f) The shares of Pioneer Parent Common Stock issuable upon
the merger of each Partnership pursuant to this Merger Agreement shall have been
authorized for listing on the New York Stock Exchange and the Toronto Stock
Exchange upon official notice of issuance.

                  (g) The parties to the merger of each Partnership having made
all filings and registrations with, and notifications to, all third parties,
including, without limitation, lenders and all appropriate regulatory
authorities, required for consummation of the transactions contemplated by this
Merger Agreement (other than the filing and recordation of appropriate merger
documents required by the DGCL, the DRULPA and the TRLPA, as applicable), and
all approvals and authorizations and consents of all third parties, including,
without limitation, lenders and all regulatory authorities, required for
consummation of the transactions contemplated by this Merger Agreement shall
have been received and shall be in full force and effect, except for such
filings, registrations, notifications, approvals, authorizations and consents,
the failure of which to make or obtain would not have a material adverse effect
on the business or financial condition of Pioneer Parent, Pioneer USA or any
Partnership.


                  (h) The absence of any opinion of counsel that the exercise by
the limited partners of any Partnership of the right to approve the merger of
such Partnership is not permitted under applicable state law.


         3.2 Conditions to Obligations of Pioneer Parent to Effect the Merger of
Each Partnership. The obligations of Pioneer Parent to effect the merger of each
Partnership shall be subject to the fulfillment (or waiver in whole or in part
by the intended beneficiary thereof in its sole discretion), at or prior to the
Closing Date, of the following additional conditions:


                  (a) Pioneer USA and each Partnership shall have performed in
all material respects their respective agreements contained in this Merger
Agreement required to be performed at or prior to the Closing Date.

                  (b) The representations and warranties of Pioneer USA and each
Partnership contained in this Merger Agreement shall be true and correct in all
material respects at and as of the Closing Date as if made at and as of such
time unless they relate to another specified time.

         3.3 Conditions to Obligations of Pioneer USA and Each Partnership to
Effect the Merger of Such Partnership. The obligations of Pioneer USA and each
Partnership to effect the merger of such Partnership shall be




                                      F-9
   155

subject to the fulfillment (or waiver in whole or in part by the intended
beneficiary thereof in its sole discretion) at or prior to the Closing Date of
the following additional conditions:


                  (a) Pioneer Parent shall have performed in all material
respects its agreements contained in this Merger Agreement required to be
performed at or prior to the Closing Date.

                  (b) The representations and warranties of Pioneer Parent
contained in this Merger Agreement shall be true and correct in all material
respects at and as of the Closing Date as if made at and as of such time unless
they relate to another specific time.


                                    ARTICLE 4
                              ADDITIONAL AGREEMENTS

         4.1 Conduct of Business Pending the Merger of Each Partnership. Each
Partnership covenants and agrees that, between the date of this Merger Agreement
and the Closing Date, unless the other parties shall otherwise agree in writing
or as otherwise contemplated in this Merger Agreement, it shall conduct its
businesses only in the ordinary course of business and in a manner consistent
with past practice, and it shall not take any action except for actions
consistent with such practice. Each Partnership shall use its reasonable best
efforts to preserve intact its business organization, to keep available the
services of its present officers, employees and consultants, and to preserve its
relationships with customers, suppliers and other persons with which it has
significant business dealings.

         4.2 Special Meetings; Proxies. As soon as reasonably practicable after
the execution of this Merger Agreement, Pioneer USA will take all action
necessary to duly call, give notice of, convene and hold the Special Meetings to
consider and vote upon approval of this Merger Agreement, the Merger Amendment,
the selection of special legal counsel for the limited partners, that counsel's
legal opinion referred to in Section 3.1(c) and the transactions contemplated
hereby and thereby. Pioneer USA will use its reasonable best efforts to solicit
from the limited partners proxies in favor of this Merger Agreement, the Merger
Amendment, the selection of special legal counsel for the limited partners, that
counsel's legal opinion referred to in Section 3.1(c) and the transactions
contemplated hereby and thereby, and to take all other action necessary or
advisable to secure any vote or consent of the limited partners of each
Partnership required by the partnership agreement of the Partnership or this
Merger Agreement or applicable law to effect the merger of the Partnership.


         4.3 Proxy Statement/Prospectus. Pioneer Parent and Pioneer USA shall
file with the SEC a registration statement that includes a preliminary proxy
statement/prospectus for each Special Meeting (the definitive form of such proxy
statement/prospectus is referred to as the "Proxy Statement/Prospectus").
Pioneer Parent and Pioneer USA shall use all reasonable commercial efforts to
have the registration statement declared effective by the SEC as promptly as
practicable. Pioneer Parent and Pioneer USA shall cause the Proxy
Statement/Prospectus to be mailed to the limited partners of each Partnership as
soon as practicable thereafter in accordance with applicable federal and state
law.

         4.4 Authorization for Shares and Stock Exchange Listing. Prior to the
Effective Time, Pioneer Parent and Pioneer USA shall have taken all action
necessary to permit Pioneer Parent to issue the number of shares of Pioneer
Parent Common Stock required to be issued pursuant to this Merger Agreement.
Each of Pioneer Parent and Pioneer USA shall use its commercially reasonable
efforts to cause the shares of Pioneer Parent Common Stock to be issued in the
merger of each Partnership to be approved for listing on the New York Stock
Exchange and the Toronto Stock Exchange, subject to official notice of issuance,
prior to the Closing Date.


         4.5 Additional Agreements. Subject to the terms and conditions herein
provided, each of the parties hereto agrees to use all reasonable commercial
efforts to obtain in a timely manner all necessary waivers, consents and
approvals and to effect all necessary registrations and filings, and to use all
reasonable commercial efforts to take, or cause to be taken, all other actions
and to do, or cause to be done, all other things necessary, proper or advisable
under applicable laws and regulations to consummate and make effective as
promptly as practicable the transactions contemplated by this Merger Agreement.



                                      F-10
   156

                                    ARTICLE 5
                                   TERMINATION

         5.1 Termination. This Merger Agreement may be terminated and the merger
of any Partnership contemplated hereby may be abandoned, in whole or in part, at
any time prior to the Effective Time, whether before or after approval of the
merger of the Partnership by its limited partners (with respect to each Special
Vote Partnership, excluding Pioneer USA and its affiliates):

                  (a) By mutual written consent of the parties;

                  (b) By any party, if:

                           (i) there shall be any applicable law, rule or
         regulation that makes consummation of the merger of any Partnership
         illegal or otherwise prohibited or if any judgment, injunction, order
         or decree enjoining any party from consummating the merger of any
         Partnership is entered and such judgment, injunction, order or decree
         shall have become final and non-appealable;

                           (ii)at the Special Meeting of each Partnership or at
         any adjournment or postponement thereof, the approval of the limited
         partners of the Partnership referred to in Section 3.1(a) shall not
         have been obtained by reason of the failure to obtain the requisite
         vote; or


                           (iii) there shall be any pending suit, action or
         proceeding filed against Pioneer Parent, Pioneer USA, any Partnership
         or any officer, director or affiliate of Pioneer Parent or Pioneer USA
         challenging the legality or any aspect of the merger of any Partnership
         or the transactions related thereto;

                  (c) By Pioneer Parent, if either Pioneer USA or any
Partnership shall have failed to perform its agreements and covenants contained
herein, which failure has a material adverse effect on Pioneer USA or such
Partnership, as the case may be, or materially and adversely affects the
transactions contemplated by this Merger Agreement;


                  (d) By Pioneer USA or any Partnership with respect to the
Partnership's merger, if Pioneer Parent shall have failed to perform its
agreements and covenants contained herein, which failure has a material adverse
effect on Pioneer USA or such Partnership, as the case may be, or materially and
adversely affects the transactions contemplated by this Merger Agreement;


                  (e) By Pioneer Parent or Pioneer USA, pursuant to Section 1.4
hereof;


                  (f) By Pioneer USA, if Pioneer USA, after considering the
written advice of outside legal counsel, determines in good faith that
termination of this Merger Agreement is required for Pioneer USA's board of
directors to comply with its fiduciary duties to its sole stockholder or to any
Partnership imposed by applicable law; or


                  (g) By Pioneer Parent, if there shall have occurred any event,
circumstance, condition, development or occurrence causing, resulting in or
having, or reasonably expected to cause, result in or have, a material adverse
effect (i) on any Partnership's business, operations, properties (taken as a
whole), condition (financial or otherwise), results of operations, assets (taken
as a whole), liabilities, cash flows or prospects, (ii) on market prices for oil
and gas prevailing generally in the oil and gas industry since the date of
determination of the oil and gas commodity prices used in the determination of
the merger value for each Partnership, (iii) on the price of Pioneer Parent
Common Stock or (iv) on the oil and gas industry generally.


         5.2 Effect of Termination. In the event of termination of this Merger
Agreement by a party as provided in Section 5.1, written notice thereof shall
promptly be given to the other parties and this Merger Agreement shall forthwith
terminate without further action by any of the parties hereto. If this Merger
Agreement is terminated as so provided, there shall be no liabilities or
obligations hereunder on the part of any party hereto except as provided in
Section 6.13 and except that nothing herein shall relieve any party hereto from
liability for any breach of this Merger Agreement.



                                      F-11
   157

                                    ARTICLE 6
                                  MISCELLANEOUS

         6.1 Headings. The headings contained in this Merger Agreement are for
reference purposes only and shall not affect in any way the meaning or
interpretation of this Merger Agreement.


         6.2 Amendment. This Merger Agreement may be supplemented, amended or
modified by an instrument in writing signed by Pioneer Parent and Pioneer USA
(on behalf of itself and as (a) the sole or managing general partner of each
Partnership, (b) the sole general partner of each Nonmanaging General Partner
and (c) attorney-in-fact for the limited partners of each Partnership) at any
time prior to the Closing Date; provided, however, that after approval by the
limited partners of each Partnership (with respect to each Special Vote
Partnership, excluding Pioneer USA and its affiliates) of this Merger Agreement,
the Merger Amendment, the selection of special legal counsel for the limited
partners and that counsel's legal opinion referred to in Section 3.1(c), no
amendment may be made which would adversely change the type or amount of, or the
method for determining, the consideration to be received upon consummation of
the merger of each Partnership or which would in any other way materially and
adversely affect the rights of such limited partners (other than a termination
of this Merger Agreement or abandonment of the merger of any Partnership).


         6.3 Waiver. At any time prior to the Closing Date, the parties hereto
may (a) extend the time for the performance of any of the obligations or other
acts of the other parties hereto, (b) waive any inaccuracies in the
representations and warranties contained herein or in any document delivered
pursuant hereto, and (c) waive compliance with any of the agreements or
conditions contained herein. Any such extension or waiver shall not operate as
an extension or waiver of, or estoppel with respect to, any subsequent failure
of compliance or other failure. Any agreement on the part of a party hereto to
any such extension or waiver shall be valid against such party if set forth in
an instrument in writing signed by such party.

         6.4 Expiration of Representations and Warranties. All representations
and warranties made pursuant to this Merger Agreement shall expire with, and be
terminated and extinguished by, the merger of each Partnership on the Closing
Date.


         6.5 Notices. All notices and other communications to be given or made
hereunder by any party shall be delivered by first class mail, or by personal
delivery, postage or fees prepaid, (a) to Pioneer Parent at 1400 Williams Square
West, 5205 North O'Connor Boulevard, Irving, Texas 75039, Attn: Scott D.
Sheffield, with a copy to Vinson & Elkins L.L.P., 3700 Trammell Crow Center,
2001 Ross Avenue, Dallas, Texas 75201, Attn: Robert L. Kimball, and (b) to the
other parties at Pioneer Natural Resources USA, Inc., 1400 Williams Square West,
5205 North O'Connor Boulevard, Irving, Texas 75039, Attn: Mark L. Withrow, with
a copy to Sayles, Lidji & Werbner, 4400 Renaissance Tower, 1201 Elm Street,
Dallas, Texas 75270, Attn: Brian M. Lidji.


         6.6 Counterparts. This Merger Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same agreement.

         6.7 Severability. If any term or other provision of this Merger
Agreement is invalid, illegal or incapable of being enforced by any rule of law
or public policy, all other conditions and provisions of this Merger Agreement
shall nevertheless remain in full force and effect so long as the economic or
legal substance of the transactions contemplated hereby is not affected in any
manner materially adverse to any party.

         6.8 Entire Agreement. This Merger Agreement, including the documents
and instruments referred to herein, constitutes the entire agreement and
supersedes all other prior agreements and undertakings, both written and oral,
between the parties, or any of them, with respect to the subject matter hereof.

         6.9 Remedies. Except as otherwise expressly provided herein, this
Merger Agreement is not intended to confer upon any other person any rights or
remedies hereunder.

         6.10 Assignment. This Merger Agreement shall not be assigned by
operation of law or otherwise without the consent of all parties hereto.


                                      F-12
   158
         6.11 No Implied Waiver. Except as expressly provided in this Merger
Agreement, no course of dealing among the parties hereto and no delay by any of
them in exercising any right, power or remedy conferred herein or now or
hereafter existing at law or in equity, by statute or otherwise, shall operate
as a waiver of, or otherwise prejudice, any such right, power or remedy.

         6.12 Governing Law. Except to the extent that TRLPA is mandatorily
applicable, this Merger Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware (regardless of the laws that
might otherwise govern under applicable principles of conflicts of law) as to
all matters.


         6.13 Expenses. Except as otherwise provided herein, to the extent the
merger of a Partnership is completed, that participating Partnership shall pay
its pro rata share, based on its reserve value, of the aggregate estimated
expenses and fees to be incurred in connection with the merger of each
Partnership with and into Pioneer USA. Except as otherwise provided herein, to
the extent the merger of a Partnership is not completed, that nonparticipating
Partnership shall pay a portion of the estimated expenses and fees of the
mergers otherwise allocable to the Partnership based on a fraction, the
numerator of which is the percentage of the Partnership's limited partnership
interests that are voted in favor of the merger proposals and the denominator of
which is the percentage of the Partnership's limited partnership interests for
which votes are cast. Pioneer Parent shall pay (a) the remainder of the
estimated expenses and fees otherwise allocable to any such nonparticipating
Partnership and (2) any expenses and fees actually incurred in excess of $2.0
million. In addition, if Pioneer Parent terminates this Merger Agreement or
abandons the merger of any Partnership pursuant to Section 5.1, Pioneer Parent
shall pay all estimated expenses and fees of such Partnership incurred in
connection with the merger of such Partnership before such termination or
abandonment.

         6.14 Liquidation. Each Partnership, Pioneer Parent and Pioneer USA
intend and agree that the merger of each Partnership shall be treated as a
liquidation of the Partnership into Pioneer USA pursuant to Section 332 of the
Internal Revenue Code of 1986, as amended, and shall make all declarations and
filings necessary to accomplish such intent and liquidation.


                            [Signature pages follow.]




                                      F-13
   159
         IN WITNESS WHEREOF, each of the parties hereto has executed this Merger
Agreement as of the date first written above.


                           
                              PIONEER NATURAL RESOURCES COMPANY


                              By:
                                 ---------------------------------------------------------
                              Name:
                                   -------------------------------------------------------
                              Title:
                                    ------------------------------------------------------


                              PIONEER NATURAL RESOURCES USA, INC.


                              By:
                                   -------------------------------------------------------
                                   Mark L. Withrow
                                   Executive Vice President, General Counsel and Secretary


                              PARTNERSHIPS:

                              Parker & Parsley 81-I, Ltd.
                              Parker & Parsley 81-II, Ltd.
                              Parker & Parsley 82-I, Ltd.
                              Parker & Parsley 82-II, Ltd.
                              Parker & Parsley 82-III, Ltd.
                              Parker & Parsley 83-A, Ltd.
                              Parker & Parsley 83-B, Ltd.
                              Parker & Parsley 84-A, Ltd.
                              Parker & Parsley 85-A, Ltd.
                              Parker & Parsley 85-B, Ltd.
                              Parker & Parsley Private Investment 85-A, Ltd.
                              Parker & Parsley Selected 85 Private Investment, Ltd.
                              Parker & Parsley 86-A, Ltd.
                              Parker & Parsley 86-B, Ltd.
                              Parker & Parsley 86-C, Ltd.
                              Parker & Parsley Private Investment 86, Ltd.
                              Parker & Parsley 87-A Conv., Ltd.
                              Parker & Parsley 87-A , Ltd.
                              Parker & Parsley 87-B Conv., Ltd.
                              Parker & Parsley 87-B, Ltd.
                              Parker & Parsley Producing Properties 87-A, Ltd.
                              Parker & Parsley Producing Properties 87-B, Ltd.
                              Parker & Parsley Private Investment 87, Ltd.
                              Parker & Parsley 88-A Conv., L.P.
                              Parker & Parsley 88-A, L.P.
                              Parker & Parsley 88-B Conv., L.P.
                              Parker & Parsley 88-B, L.P.
                              Parker & Parsley 88-C Conv., L.P.
                              Parker & Parsley 88-C, L.P.
                              Parker & Parsley Producing Properties 88-A, L.P.
                              Parker & Parsley Private Investment 88, L.P.
                              Parker & Parsley 89-A Conv., L.P.
                              Parker & Parsley 89-A, L.P.
                              Parker & Parsley 89-B Conv., L.P.
                              Parker & Parsley 89-B, L.P.
                              Parker & Parsley Private Investment 89, L.P.




                                      F-14
   160


                           
                              Parker & Parsley 90-A Conv., L.P.
                              Parker & Parsley 90-A, L.P.
                              Parker & Parsley 90-B Conv., L.P.
                              Parker & Parsley 90-B, L.P.
                              Parker & Parsley 90-C Conv., L.P.
                              Parker & Parsley 90-C, L.P.
                              Parker & Parsley Private Investment 90, L.P.
                              Parker & Parsley 90 Spraberry Private Development, L.P.
                              Parker & Parsley 91-A, L.P.
                              Parker & Parsley 91-B, L.P.

                              By:  Pioneer  Natural  Resources  USA,  Inc.,  as the sole or
                                   managing  general partner of each Partnership


                              By:
                                   -------------------------------------------------------
                                   Mark L. Withrow
                                   Executive Vice President, General Counsel and Secretary


                              By:  Pioneer  Natural  Resources USA, Inc., as the sole general
                                   partner of each Nonmanaging General Partner


                              By:
                                   -------------------------------------------------------
                                   Mark L. Withrow
                                   Executive Vice President, General Counsel and Secretary


                              By:  Pioneer Natural  Resources USA, Inc., as  attorney-in-fact
                                   for the limited partners of each Partnership


                              By:
                                   -------------------------------------------------------
                                   Mark L. Withrow
                                   Executive Vice President, General Counsel and Secretary





                                      F-15
   161

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 81-I, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

              PROXY STATEMENT/PROSPECTUS DATED            , 2001

                                   ----------

                THE DATE OF THIS SUPPLEMENT IS         , 2001

                                   ----------


         This document contains important information specific to Parker &
Parsley 81-I, Ltd. and supplements the proxy statement/prospectus dated        ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


         This document contains the following information concerning Parker &
Parsley 81-I, Ltd.:

         o A table containing:

           - the aggregate initial investment by the limited partners


           - the aggregate historical limited partner distributions through July
             31, 2001

           - the merger value attributable to partnership interests of limited
             partners, excluding Pioneer USA

           - the merger value per $1,000 limited partner investment

           - the merger value per $1,000 limited partner investment as a
             multiple of distributions for the past four quarterly distributions
             including the distribution in July 2001


           - the book value per $1,000 limited partner investment as of
             March 31, 2001 and as of December 31, 2000


           - the going concern value per $1,000 limited partner investment

           - the liquidation value per $1,000 limited partner investment


           - the ordinary tax loss per $1,000 limited partner investment in year
             of initial investment

         o Information about:


           - the legal opinion for the limited partners

           - the term of the partnership


         o The partnership's financial statements, including management's
           discussion and analysis of financial condition and results of
           operations, for the three months ended March 31, 2001

         o The partnership's financial statements, including management's
           discussion and analysis of financial condition and results of
           operations, for the year ended December 31, 2000

         o Selected historical financial data for the partnership for the three
           months ended March 31, 2001 and 2000 and the five years ended
           December 31, 2000


                                      -1-
   162


                           PARKER & PARSLEY 81-I, LTD.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                                         
Aggregate Initial Investment by the Limited Partners(a)                                                      $      7,410

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                                  $      4,869

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)        $        629

Merger Value per $1,000 Limited Partner Investment(b), (c)                                                   $      90.13

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                                3.50 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                          $      19.17

      --    as of December 31, 2000(c)                                                                       $      20.30

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                            $      81.97

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                              $      87.44

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)                $        320



----------

(a)      Stated in thousands.


(b)      The merger value for the partnership is equal to the sum of the present
         value of estimated future net revenues from the partnership's estimated
         oil and gas reserves and its net working capital, in each case as of
         March 31, 2001, less its pro rata share, based on its reserve value, of
         the estimated expenses and fees of the mergers of all of the
         partnerships and less the cash distribution on or about July 9, 2001,
         by the partnership to its partners.

(c)      Interests in some partnerships were sold in units at prices other than
         $1,000. We have presented this information based on a $1,000 initial
         investment for ease of use and comparison among partnerships. You
         should not assume that the amount shown per $1,000 investment is the
         same as the value or amount attributable to a single unit investment.

(d)      The going concern value for the partnership is based upon: (1) the sum
         of (A) the estimated net cash flow from the sale of the partnership's
         reserves during a 10-year operating period and (B) the estimated
         residual value from the sale of the partnership's remaining reserves at
         the end of the operating period, in each case using the same pricing
         and discount rate as in the merger value calculation, less (2)
         partnership level general and administrative expenses.

(e)      The liquidation value for the partnership is based upon the sale of the
         partnership's reserves at the reserve value, less liquidation expenses
         which are estimated to be the sum of (1) the partnership's pro rata
         share of the merger expenses and fees described in footnote (b) above
         and (2) 3% of the partnership's reserve value. The liquidation expenses
         represent the estimated costs to retain an investment banker or broker
         to sell the assets of the partnership and the legal and other closing
         costs associated with such transaction, including the wind-down costs
         of the partnership.

(f)      Your ability to use your distributive share of the partnership's loss
         to offset your other income may have been subject to certain
         limitations at your level as a partner, and you may therefore wish to
         consult your tax advisor to determine the additional value, if any,
         actually realized by you in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

         The partnership agreement for the partnership requires that special
legal counsel render an opinion on behalf of the limited partners to Pioneer USA
that (1) neither the grant nor the exercise of the right to approve the merger
of the partnership by its limited partners will adversely affect the federal
income tax classification of the partnership or any of its limited partners; and
(2) neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

         The term of the partnership shall continue until terminated in
accordance with the applicable provisions of its partnership agreement.






                                      -2-

   163


                           PARKER & PARSLEY 81-I, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   164



                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS





                                                      March 31,     December 31,
                                                        2001           2000
                                                    ------------    ------------
                                                    (Unaudited)
                                                              
                   ASSETS

Current assets:
  Cash                                              $     37,628    $     38,546
  Accounts receivable - oil and gas sales                 55,070          63,269
                                                    ------------    ------------
        Total current assets                              92,698         101,815
                                                    ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                 5,245,898       5,245,144
Accumulated depletion                                 (5,144,081)     (5,142,190)
                                                    ------------    ------------
        Net oil and gas properties                       101,817         102,954
                                                    ------------    ------------
                                                    $    194,515    $    204,769
                                                    ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $      9,796    $      8,817

Partners' capital:
  General partners                                        42,670          45,564
  Limited partners (1,482 interests)                     142,049         150,388
                                                    ------------    ------------
                                                         184,719         195,952
                                                    ------------    ------------
                                                    $    194,515    $    204,769
                                                    ============    ============


  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2

   165



                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                     Three months ended
                                                          March 31,
                                                   -----------------------
                                                      2001         2000
                                                   ----------   ----------
                                                          
Revenues:
  Oil and gas                                      $  108,191   $   94,181
  Interest                                                719          563
                                                   ----------   ----------
                                                      108,910       94,744
                                                   ----------   ----------
Costs and expenses:
  Oil and gas production                               44,964       40,666
  General and administrative                            4,857        2,921
  Depletion                                             1,891        1,618
                                                   ----------   ----------
                                                       51,712       45,205
                                                   ----------   ----------
Net income                                         $   57,198   $   49,539
                                                   ==========   ==========
Allocation of net income:
  General partners                                 $   14,328   $   12,628
                                                   ==========   ==========
  Limited partners                                 $   42,870   $   36,911
                                                   ==========   ==========
Net income per limited partnership interest        $    28.93   $    24.91
                                                   ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   166



                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                   General         Limited
                                   partners        partners         Total
                                 ------------    ------------    ------------
                                                        

Balance at January 1, 2001       $     45,564    $    150,388    $    195,952

    Distributions                     (17,222)        (51,209)        (68,431)

    Net income                         14,328          42,870          57,198
                                 ------------    ------------    ------------

Balance at March 31, 2001        $     42,670    $    142,049    $    184,719
                                 ============    ============    ============





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4

   167



                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                          Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $   57,198    $   49,539
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            1,891         1,618
  Changes in assets and liabilities:
       Accounts receivable                                  8,199        (6,807)
       Accounts payable                                       979          (173)
                                                       ----------    ----------
         Net cash provided by operating activities         68,267        44,177
                                                       ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                        (754)         (110)

Cash flows used in financing activities:
  Cash distributions to partners                          (68,431)      (41,860)
                                                       ----------    ----------
Net increase (decrease) in cash                              (918)        2,207
Cash at beginning of period                                38,546        38,716
                                                       ----------    ----------
Cash at end of period                                  $   37,628    $   40,923
                                                       ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.




                                        5
   168



                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 81-I, Ltd. (the "Partnership") is a limited partnership
organized in 1981 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 15% to $108,191 for the three
months ended March 31, 2001 as compared to $94,181 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 2,157
barrels of oil, 770 barrels of natural gas liquids ("NGLs") and 5,562 mcf of gas
were sold, or 3,854 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 2,402 barrels of oil, 1,217 barrels of NGLs and 6,102 mcf
of gas were sold, or 4,636 BOEs.



                                        6
   169



The average price received per barrel of oil increased $1.39, or 5%, from $27.16
for the three months ended March 31, 2000 to $28.55 for the same period in 2001.
The average price received per barrel of NGLs increased $2.13, or 15%, from
$14.58 for the three months ended March 31, 2000 to $16.71 for the same period
in 2001. The average price received per mcf of gas increased 232% from $1.83
during the three months ended March 31, 2000 to $6.07 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $51,712 for the three months ended March
31, 2001 as compared to $45,205 for the same period in 2000, an increase of
$6,507, or 14%. This increase was primarily due to increases in production
costs, general and administrative expenses ("G&A") and depletion.

Production costs were $44,964 for the three months ended March 31, 2001 and
$40,666 for the same period in 2000 resulting in a $4,298 increase, or 11%. The
increase was due to additional well maintenance costs incurred to stimulate well
production and higher production taxes associated with higher oil and gas
prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 66% from $2,921 for the three months ended March 31, 2000 to $4,857
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $1,891 for the three months ended March 31, 2001 as compared to
$1,618 for the same period in 2000, an increase of $273, or 17%. This increase
was primarily due to a downward revision to one well's proved reserves during
the three months ended March 31, 2001, offset by a decline in oil production of
245 barrels for the period ended March 31, 2001 compared to the same period in
2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $24,090 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $14,166 and a
reduction in working capital of $16,158, offset by increases in production costs
of $4,298 and G&A expenses of $1,936. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an



                                        7
   170


additional $444 to oil and gas receipts and $13,722 resulting from an increase
in production during 2001 as compared to the same period in 2000. The increase
in production costs was primarily due to additional well maintenance costs
incurred to stimulate well production and increased production taxes associated
with higher oil and gas prices. The increase in G&A was primarily due to a
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues and
an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $68,431, of which $17,222 was distributed to the general partners and
$51,209 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $41,860, of which $10,466 was distributed to
the general partners and $31,394 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.




                                        8


   171
                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999




   172





                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 81-I, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 81-I, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 81-I, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                      Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   173


                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                             2000                 1999
                                                                       ----------------     ----------------
                     ASSETS

                                                                                      
Current assets:
  Cash                                                                 $       38,546       $       38,716
  Accounts receivable - oil and gas sales                                      63,269               34,340
                                                                         ------------         ------------

          Total current assets                                                101,815               73,056
                                                                         ------------         ------------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                      5,245,144            5,240,632
Accumulated depletion                                                      (5,142,190)          (5,133,431)
                                                                         ------------         ------------

          Net oil and gas properties                                          102,954              107,201
                                                                         ------------         ------------

                                                                       $      204,769       $      180,257
                                                                        =============        =============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                                         $        8,817       $       10,041

Partners' capital:
  General partners                                                             45,564               38,221
  Limited partners (1,482 interests)                                          150,388              131,995
                                                                         ------------         ------------

                                                                              195,952              170,216
                                                                         ------------         ------------

                                                                       $      204,769       $      180,257
                                                                        =============        =============
















   The accompanying notes are an integral part of these financial statements.



                                       3
   174


                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                        2000        1999        1998
                                                     ---------   ---------   ---------

                                                                    
Revenues:
  Oil and gas                                        $ 416,230   $ 260,652   $ 199,789
  Interest                                               3,071       1,858       2,462
  Gain on disposition of assets                             --          --          67
                                                     ---------   ---------   ---------

                                                       419,301     262,510     202,318
                                                     ---------   ---------   ---------

Costs and expenses:
  Oil and gas production                               174,233     165,810     157,631
  General and administrative                            15,697      13,087       8,892
  Impairment of oil and gas properties                      --          --      50,343
  Depletion                                              8,759      11,881     116,799
                                                     ---------   ---------   ---------

                                                       198,689     190,778     333,665
                                                     ---------   ---------   ---------

Net income (loss)                                    $ 220,612   $  71,732   $(131,347)
                                                     =========   =========   =========

Allocation of net income (loss):
  General partners                                   $  56,242   $  19,205   $  (7,775)
                                                     =========   =========   =========

  Limited partners                                   $ 164,370   $  52,527   $(123,572)
                                                     =========   =========   =========

Net income (loss) per limited partnership interest   $  110.91   $   35.44   $  (83.38)
                                                     =========   =========   =========







   The accompanying notes are an integral part of these financial statements.



                                       4
   175


                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                                           General              Limited
                                                                           partners             partners               Total
                                                                        --------------       --------------       ---------------
                                                                                                         
Partners' capital at January 1, 1998                                    $       52,826       $      295,972       $     348,798

   Distributions                                                               (10,054)             (45,727)            (55,781)

   Net loss                                                                     (7,775)            (123,572)           (131,347)
                                                                          ------------         ------------         -----------

Partners' capital at December 31, 1998                                          34,997              126,673             161,670

   Distributions                                                               (15,981)             (47,205)            (63,186)

   Net income                                                                   19,205               52,527              71,732
                                                                          ------------         ------------         -----------

Partners' capital at December 31, 1999                                          38,221              131,995             170,216

   Distributions                                                               (48,899)            (145,977)           (194,876)

   Net income                                                                   56,242              164,370             220,612
                                                                          ------------         ------------         -----------

Partners' capital at December 31, 2000                                  $       45,564       $      150,388       $     195,952
                                                                         =============        =============        ============






















   The accompanying notes are an integral part of these financial statements.



                                       5
   176


                          PARKER & PARSLEY 81-I, LTD.
                         (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                        For the years ended December 31





                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                        
Cash flows from operating activities:
   Net income (loss)                                                    $     220,612        $      71,732       $     (131,347)
   Adjustments to reconcile net income (loss) to
      net cash provided by operating activities:
         Impairment of oil and gas properties                                     -                    -                 50,343
         Depletion                                                              8,759               11,881              116,799
         Gain on disposition of assets                                            -                    -                    (67)
   Changes in assets and liabilities:
         Accounts receivable                                                  (28,929)             (11,525)              12,794
         Accounts payable                                                      (1,224)               2,906               (3,523)
                                                                          -----------           ----------         ------------

             Net cash provided by operating activities                        199,218               74,994               44,999
                                                                          -----------          -----------         ------------

Cash flows from investing activities:
   Additions to oil and gas properties                                         (4,512)              (3,421)              (2,481)
   Proceeds from asset dispositions                                               -                    -                 14,234
                                                                          -----------          -----------         ------------

             Net cash provided by (used in) investing activities               (4,512)              (3,421)              11,753
                                                                          -----------          -----------         ------------

Cash flows used in financing activities:
   Cash distributions to partners                                            (194,876)             (63,186)             (55,781)
                                                                          -----------          -----------         ------------

Net increase (decrease) in cash                                                  (170)               8,387                  971
Cash at beginning of year                                                      38,716               30,329               29,358
                                                                          -----------          -----------         ------------

Cash at end of year                                                     $      38,546        $      38,716       $       30,329
                                                                         ============         ============        =============




   The accompanying notes are an integral part of these financial statements.



                                       6
   177


                           PARKER & PARSLEY 81-I, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 81-I, Ltd. (the "Partnership") is a limited partnership
organized in 1981 under the laws of the State of Texas. The Partnership's
general partners are Pioneer Natural Resources USA, Inc. ("Pioneer USA") and P&P
Employees 81-I, Ltd. ("EMPL"). The Partnership's managing general partner is
Pioneer USA.

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.



                                       7
   178

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved



                                       8
   179

in the industry. As a result, the Partnership recognized a non-cash impairment
provision of $50,343 related to its proved oil and gas properties during 1998.

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $308,345 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                              2000                1999                1998
                                                                         --------------      --------------      --------------

                                                                                                        
        Net income (loss) per statements of operations                   $     220,612       $      71,732       $    (131,347)
        Depletion and depreciation provisions for tax
           reporting purposes less than amounts for
           financial reporting purposes                                          6,157               9,884             114,643
        Impairment of oil and gas properties for
           financial reporting purposes                                            -                   -                50,343
        Other, net                                                                (447)                (62)                 81
                                                                           -----------        ------------         -----------

                Net income per Federal income tax returns                $     226,322       $      81,554       $      33,720
                                                                          ============        ============        ============


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                        
        Property acquisition costs                                      $        4,512       $       3,421       $        2,481
                                                                         =============        ============        =============


        Capitalized oil and gas properties consist of the following:



                                                                                                   2000                1999
                                                                                             ----------------    ----------------
                                                                                                           
        Proved properties:
           Property acquisition costs                                                       $       156,084      $       156,084
           Completed wells and equipment                                                          5,089,060            5,084,548
                                                                                              -------------        -------------

                                                                                                  5,245,144            5,240,632
        Accumulated depletion                                                                    (5,142,190)          (5,133,431)
                                                                                              -------------        -------------

                Net oil and gas properties                                                  $       102,954      $       107,201
                                                                                             ==============       ==============



NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                       9
   180



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------

                                                                                                         
        Payment of lease operating and supervision
           charges in accordance with standard industry
           operating agreements                                          $      78,719       $      73,881        $     76,809

        Reimbursement of general and administrative
           expenses                                                      $      12,487       $       7,820        $      6,250


        Pioneer USA, EMPL and the Partnership are parties to the Partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 60% and the
remaining portion is owned by former affiliates.

        The costs and revenues of the Partnership are allocated as follows:



                                                                                        General                   Limited
                                                                                        partners                  partners
                                                                                        --------                  --------
                                                                                                               
     Revenues:
        Proceeds from property dispositions prior to cost
          recovery                                                                         10%                       90%
        All other Partnership revenues                                                     25%                       75%
     Costs and expenses:
        Lease acquisition costs, drilling and completion
          costs and all other costs                                                        10%                       90%
        Operating costs, direct costs and general and
          administrative expenses                                                          25%                       75%


NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                       10
   181




                                                Oil and NGLs            Gas
                                                  (bbls)               (mcf)
                                                 --------            --------

                                                              
Net proved reserves at January 1, 1998            131,090             275,544
Revisions                                         (70,930)           (119,307)
Production                                        (13,937)            (24,638)
                                                 --------            --------

Net proved reserves at December 31, 1998           46,223             131,599
Revisions                                         160,567             219,656
Production                                        (14,970)            (28,708)
                                                 --------            --------

Net proved reserves at December 31, 1999          191,820             322,547
Revisions                                          33,336             130,129
Production                                        (13,976)            (25,901)
                                                 --------            --------

Net proved reserves at December 31, 2000          211,180             426,775
                                                 ========            ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.30 per barrel of NGLs and $7.65 per mcf of gas,
discounted at 10% was approximately $1,915,000 and undiscounted was $3,748,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.






                                       11
   182




                                                                                  For the years ended December 31,
                                                                        ---------------------------------------------------
                                                                              2000                1999               1998
                                                                        ----------------    ----------------   ----------------
                                                                                             (in thousands)
                                                                                                      
Oil and gas producing activities:
   Future cash inflows                                                  $         7,853     $        4,776     $           583
   Future production costs                                                       (4,105)            (3,078)               (433)
                                                                          -------------       ------------       -------------

                                                                                  3,748              1,698                 150
   10% annual discount factor                                                    (1,833)              (734)                (64)
                                                                          -------------       ------------       -------------

   Standardized measure of discounted future net cash flows             $         1,915     $          964     $            86
                                                                         ==============      =============      ==============





                                                                                  For the years ended December 31,
                                                                        ---------------------------------------------------
                                                                              2000                1999               1998
                                                                        ----------------    ----------------   ----------------
                                                                                             (in thousands)
                                                                                                      
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs                        $          (242)    $          (95)    $          (42)
      Net changes in prices and production costs                                    888                180               (301)
      Revisions of previous quantity estimates                                      415                788               (112)
      Accretion of discount                                                          96                  8                 52
      Changes in production rates, timing and other                                (206)                (3)               (33)
                                                                          -------------       ------------       ------------

      Change in present value of future net revenues                                951                878               (436)
                                                                          -------------       ------------       ------------

      Balance, beginning of year                                                    964                 86                522
                                                                          -------------       ------------       ------------

      Balance, end of year                                              $         1,915     $          964     $           86
                                                                         ==============      =============      =============


NOTE 8. MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:


                                                                                2000                1999               1998
                                                                              --------            --------           --------

                                                                                                            
                    Plains Marketing, L.P.                                       54%                 51%                 -
                    Genesis Crude Oil, L.P.                                       -                   -                 59%
                    Western Gas Resources, Inc.                                   -                   6%                18%
                    Exxon Corporation                                             8%                  7%                11%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $19,892 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.







                                       12
   183


NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        General partners - The general partners of the Partnership are Pioneer
        USA and EMPL. Pioneer USA, the managing general partner, has the power
        and authority to manage, control and administer all Partnership affairs.
        As managing general partner and operator of the Partnership's
        properties, all production expenses are incurred by Pioneer USA and
        billed to the Partnership. The majority of the Partnership's oil and gas
        revenues are received directly by the Partnership, however, a portion of
        the oil and gas revenue is initially received by Pioneer USA prior to
        being paid to the Partnership.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $7,410,000. The general partners are required to contribute amounts
        equal to 10% of Partnership expenditures for lease acquisition, drilling
        and completion and 25% of direct, general and administrative and
        operating expenses.



                                       13




   184
                           PARKER & PARSLEY 81-I, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
     RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 60% to $416,230 for 2000 as
compared to $260,652 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decrease in production. In 2000, 8,793
barrels of oil, 5,183 barrels of natural gas liquids ("NGLs") and 25,901 mcf of
gas were sold, or 18,293 barrel of oil equivalents ("BOEs"). In 1999, 9,249
barrels of oil, 5,721 barrels of NGLs and 28,708 mcf of gas were sold, or 19,755
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.32, or 73%, from
$16.94 in 1999 to $29.26 in 2000. The average price received per barrel of NGLs
increased $5.38, or 58%, from $9.22 in 1999 to $14.60 in 2000. The average price
received per mcf of increased 81% from $1.78 in 1999 to $3.22 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $198,689 as compared to $190,778
in 1999, an increase of $7,911, or 4%. The increase was primarily due to an
increase in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $174,233 in 2000 and $165,810 in 1999, resulting in an
$8,423 increase, or 5%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices, offset by less well maintenance
costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
20% from $13,087 in 1999 to $15,697 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $12,487 in 2000 and $7,820 in 1999
for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $8,759 in 2000 as compared to $11,881 in 1999, representing a
decrease of $3,122, or 26%. This decrease was primarily due to a 20,821 barrels
of oil increase in proved reserves during 2000 as a result of the higher
commodity prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 30% to $260,652 from
$199,789 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production. In 1999, 9,249 barrels of oil, 5,721
barrels of NGLs and 28,708 mcf of gas were sold, or 19,755 BOEs. In 1998, 9,634
barrels of oil, 4,303 barrels of NGLs and 24,638 mcf of gas were sold, or 18,043
BOEs.



   185

The average price received per barrel of oil increased $3.61, or 27%, from
$13.33 in 1998 to $16.94 in 1999. The average price received per barrel of NGLs
increased $2.82, or 44%, from $6.40 in 1998 to $9.22 in 1999. The average price
received per mcf of gas remained unchanged at $1.78 in 1998 and 1999.

Total costs and expenses decreased in 1999 to $190,778 as compared to $333,665
in 1998, a decrease of $142,887, or 43%. The decrease was primarily due to
declines in depletion and the impairment of oil and gas properties, offset by an
increase in production costs and G&A.

Production costs were $165,810 in 1999 and $157,631 in 1998, resulting in an
$8,179 increase, or 5%. The increase was due to additional well maintenance
costs incurred to stimulate well production and an increase in production taxes
due to increased oil and gas revenues, offset by a decline in ad valorem taxes.

During this period, G&A increased 47% from $8,892 in 1998 to $13,087 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $7,820 in
1999 and $6,250 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $50,343 related to its oil and gas properties during 1998.

Depletion was $11,881 in 1999 compared to $116,799 in 1998, representing a
decrease of $104,918, or 90%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 104,672 barrels of oil
during 1999 as a result of the higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 385
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $124,224 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $156,791, offset by increases in production costs paid
of $8,423, G&A expenses paid of $2,610 and working capital of $21,534. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $187,015 to oil and gas receipts,
offset by $30,224 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices, offset by lower well maintenance
costs. The increase in G&A was primarily due to higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.



   186

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to upgrades of equipment on various oil and gas properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $194,876, of which $48,899 was
distributed to the general partners and $145,977 to the limited partners. In
1999, cash distributions to the partners were $63,186, of which $15,981 was
distributed to the general partners and $47,205 to the limited partners.








   187



                           PARKER & PARSLEY 81-I, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   94,181   $  416,230   $  260,652   $  199,789   $  279,957   $  396,128
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   50,343   $  255,709   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $          $       --   $       --   $       --   $       --   $       --   $   30,621
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   49,539   $  220,612   $   71,732   $ (131,347)  $ (241,864)  $  203,620
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $   12,628   $   56,242   $   19,205   $   (7,775)  $  (11,941)  $   54,950
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   36,911   $  164,370   $   52,527   $ (123,572)  $ (229,923)  $  148,670
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    24.91   $   110.91   $    35.44   $   (83.38)  $  (155.14)  $   100.32
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    21.18   $    98.50   $    31.85   $    30.85   $    68.90   $   107.95(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  187,763   $  204,769   $  180,257   $  168,805   $  359,456   $  734,832
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $20.66
     in 1996.



   188
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 81-II LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED        , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS        , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
81-II Ltd. and supplements the proxy statement/prospectus dated          , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc.,
by which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 81-II Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                       -1-
   189

                           PARKER & PARSLEY 81-II LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                         
Aggregate Initial Investment by the Limited Partners(a)                                     $   6,440

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                 $   5,422

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer   $     470
USA(a), (b)

Merger Value per $1,000 Limited Partner Investment(b), (c)                                  $   73.34

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the        3.02 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

        -- as of March 31, 2001(c)                                                          $   82.82

        -- as of December 31, 2000(c)                                                       $   84.93

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                           $   66.14

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                             $   71.21

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment       $     290
(c), (f)




----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
status or classification of the partnership or any of its limited partners; and
(2) neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.




                                       -2-
   190

                          PARKER & PARSLEY 81-II, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   191



                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS




                                                      March 31,      December 31,
                                                         2001            2000
                                                     ------------    ------------
                                                     (Unaudited)
                                                               
                 ASSETS
Current assets:
  Cash                                               $     32,452    $     29,376
  Accounts receivable - oil and gas sales                  53,674          64,821
                                                     ------------    ------------
        Total current assets                               86,126          94,197
                                                     ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                  5,347,556       5,345,296
Accumulated depletion                                  (4,832,578)     (4,821,914)
                                                     ------------    ------------
        Net oil and gas properties                        514,978         523,382
                                                     ------------    ------------
                                                     $    601,104    $    617,579
                                                     ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $      9,487    $      9,253

Partners' capital:
  General partners                                         58,234          61,405
  Limited partners (1,153 interests)                      533,383         546,921
                                                     ------------    ------------
                                                          591,617         608,326
                                                     ------------    ------------
                                                     $    601,104    $    617,579
                                                     ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   192

                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  108,066   $   70,001
  Interest                                           682          397
                                              ----------   ----------
                                                 108,748       70,398
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                          50,840       48,539
  General and administrative                       4,448        2,190
  Depletion                                       10,664       11,747
                                              ----------   ----------
                                                  65,952       62,476
                                              ----------   ----------
Net income                                    $   42,796   $    7,922
                                              ==========   ==========
Allocation of net income:
  General partners                            $   12,044   $    3,743
                                              ==========   ==========
  Limited partners                            $   30,752   $    4,179
                                              ==========   ==========
Net income per limited partnership interest   $    26.67   $     3.62
                                              ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   193

                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                              General       Limited
                              partners      partners       Total
                             ----------    ----------    ----------
                                                
Balance at January 1, 2001   $   61,405    $  546,921    $  608,326

    Distributions               (15,215)      (44,290)      (59,505)

    Net income                   12,044        30,752        42,796
                             ----------    ----------    ----------

Balance at March 31, 2001    $   58,234    $  533,383    $  591,617
                             ==========    ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   194

                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                       Three months ended
                                                            March 31,
                                                     ------------------------
                                                        2001          2000
                                                     ----------    ----------
                                                             
Cash flows from operating activities:
  Net income                                         $   42,796    $    7,922
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         10,664        11,747
  Changes in assets and liabilities:
       Accounts receivable                               11,147        (9,005)
       Accounts payable                                     234          (108)
                                                     ----------    ----------
         Net cash provided by operating activities       64,841        10,556
                                                     ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                    (2,260)       (1,329)

Cash flows used in financing activities:
  Cash distributions to partners                        (59,505)      (16,316)
                                                     ----------    ----------
Net increase (decrease) in cash                           3,076        (7,089)
Cash at beginning of period                              29,376        30,160
                                                     ----------    ----------
Cash at end of period                                $   32,452    $   23,071
                                                     ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   195

                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.  Organization and nature of operations

Parker & Parsley 81-II (the "Partnership") is a limited partnership organized in
1981 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The partnership's oil and gas revenues increased 54% to $108,066 for the three
months ended March 31, 2001 as compared to $70,001 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 2,169 barrels
of oil, 535 barrels of natural gas liquids ("NGLs") and 5,731 mcf of gas were
sold, or 3,659 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 2,052 barrels of oil, 685 barrels of NGLs and 1,489 mcf of gas
were sold, or 2,985 BOEs.



                                        6
   196

The average price received per barrel of oil increased $.52, or 2%, from $27.34
for the three months ended March 31, 2000 to $27.86 for the same period in 2001.
The average price received per barrel of NGLs increased $3.36, or 19%, from
$17.54 for the three months ended March 31, 2000 to $20.90 for the same period
in 2001. The average price received per mcf of gas increased 405% from $1.26
during the three months ended March 31, 2000 to $6.36 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $65,952 for the three months ended March
31, 2001 as compared to $62,476 for the same period in 2000, an increase of
$3,476, or 6%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $50,840 for the three months ended March 31, 2001 and
$48,539 for the same period in 2000 resulting in a $2,301 increase, or 5%. The
increase was primarily due to higher production taxes of associated with higher
oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 103% from $2,190 for the three months ended March 31, 2000 to $4,448
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $10,664 for the three months ended March 31, 2001 as compared to
$11,747 for the same period in 2000, a decrease of $1,083, or 9%. This decrease
was primarily due to a positive revision to proved reserves on one well during
the three months ended March 31, 2001.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $54,285 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $38,350 and a
reduction in working capital of $20,494, offset by increases in production costs
of $2,301 and G&A expenses of $2,258. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $11,234 to oil and gas receipts and $27,116 resulting from an
increase in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to a higher percentage of the managing general partner's G&A being allocated



                                        7
   197

(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $59,505, of which $15,215 was distributed to the general partners and
$44,290 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $16,316, of which $3,363 was distributed to
the general partners and $12,953 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   198






                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999







   199




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 81-II, Ltd.
 (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 81-II, Ltd. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 81-II, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                           Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   200



                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                         2000        1999
                                                     ----------   ---------
           ASSETS
           ------
                                                           
Current assets:
 Cash                                               $    29,376  $   30,160
 Accounts receivable - oil and gas sales                 64,821      27,908
                                                     ----------   ---------

      Total current assets                               94,197      58,068
                                                     ----------   ---------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,345,296   5,338,113
Accumulated depletion                                (4,821,914) (4,776,074)
                                                     ----------   ---------


     Net oil and gas properties                         523,382     562,039
                                                     ----------   ---------

                                                       $617,579  $  620,107
                                                     ==========   =========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------
Current liabilities:
 Accounts payable - affiliate                       $     9,253  $   10,581

Partners' capital:
  General partners                                       61,405      58,558
  Limited partners (1,153 interests)                    546,921     550,968
                                                     ----------   ---------

                                                        608,326     609,526
                                                     ----------   ---------
                                                    $   617,579  $  620,107
                                                     ==========   =========




   The accompanying notes are an integral part of these financial statements.



                                       3
   201



                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                             2000        1999       1998
                                          --------    --------    --------
                                                        
Revenues:
  Oil and gas                            $ 387,180   $ 204,717   $ 209,110
  Interest                                   2,775       1,395       1,725
  Gain on disposition of assets                -           240         -
                                          --------    --------    --------

                                           389,955     206,352     210,835
                                          --------    --------    --------

Costs and expenses:
  Oil and gas production                   189,764     140,847     173,960
  General and administrative                13,791       9,864       7,867
  Impairment of oil and gas properties         -           -        30,131
  Depletion                                 45,840      49,409      95,466
                                          --------    --------    --------

                                           249,395     200,120     307,424
                                          --------    --------    --------

Net income (loss)                        $ 140,560   $   6,232   $ (96,589)
                                          ========    ========    ========

Allocation of net income (loss):
  General partners                       $  41,791   $   8,423   $  (5,308)
                                          ========    ========    ========

  Limited partners                       $  98,769   $  (2,191)  $ (91,281)
                                          ========    ========    ========

Net income (loss) per limited
  partnership interest                   $   85.66   $   (1.90)  $  (79.17)
                                          ========    ========    ========





   The accompanying notes are an integral part of these financial statements.



                                       4
   202



                         PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                           General      Limited
                                           partners     partners    Total
                                          ---------    ---------  ---------
                                                          
Partners' capital at January 1, 1998      $ 76,354     $706,525   $782,879

   Distributions                           (11,831)     (34,220)   (46,051)

   Net loss                                 (5,308)     (91,281)   (96,589)
                                          ---------    ---------  ---------

Partners' capital at December 31, 1998      59,215      581,024    640,239

   Distributions                            (9,080)     (27,865)   (36,945)

   Net income (loss)                         8,423       (2,191)     6,232
                                          ---------    ---------  ---------

Partners' capital at December 31, 1999      58,558      550,968    609,526

   Distributions                           (38,944)    (102,816)  (141,760)

   Net income                               41,791       98,769    140,560
                                          ---------    ---------  ---------

Partners' capital at December 31, 2000    $ 61,405     $546,921   $608,326
                                          =========    =========  =========






   The accompanying notes are an integral part of these financial statements.



                                       5
   203



                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                      2000        1999        1998
                                                   ---------    ---------  ---------
                                                                 
Cash flows from operating activities:
  Net income (loss)                                $140,560     $ 6,232    $(96,589)
  Adjustments to reconcile net income (loss) to
   net cash provided by operating activities:
     Impairment of oil and gas properties               -           -        30,131
     Depletion                                       45,840      49,409      95,466
     Gain on disposition of assets                      -          (240)        -
  Changes in assets and liabilities:
     Accounts receivable                            (36,913)     (3,325)     15,443
     Accounts payable                                (1,328)      3,022      (3,482)
                                                   ---------    ---------  ---------

        Net cash provided by operating activities   148,159      55,098      40,969
                                                   ---------    ---------  ---------
Cash flows from investing activities:
  Additions to oil and gas properties                (7,183)     (4,254)     (8,322)
  Proceeds from asset dispositions                      -           690         -
                                                   ---------    ---------  ---------

        Net cash used in investing activities        (7,183)     (3,564)     (8,322)
                                                   ---------    ---------  ---------

Cash flows used in financing activities:
  Cash distributions to partners                   (141,760)    (36,945)    (46,051)
                                                   ---------    ---------  ---------

Net increase (decrease) in cash                        (784)     14,589     (13,404)
Cash at beginning of year                            30,160      15,571      28,975
                                                   ---------    ---------  ---------

Cash at end of year                                $ 29,376     $30,160    $ 15,571
                                                   =========    =========  =========




   The accompanying notes are an integral part of these financial statements.



                                       6
   204



                          PARKER & PARSLEY 81-II, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.     ORGANIZATION AND NATURE OF OPERATIONS

     Parker & Parsley 81-II (the "Partnership") is a limited partnership
organized in 1981 under the laws of the State of Texas. The Partnership's
general partners are Pioneer Natural Resources USA, Inc. ("Pioneer USA") and P&P
Employees 81-II, Ltd. ("EMPL"). The Partnership's managing general partner is
Pioneer USA.

     The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.     SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

     A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

     Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

     Impairment of long-lived assets - In accordance with Statement of Financial
Accounting Standards No. 121, "Accounting for the Impairment of Long-Lived
Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

     Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

                                       7
   205

     Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

     Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

     Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

     General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

     Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

     Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

     Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved

                                       8
   206

in the industry. As a result, the Partnership recognized a non-cash impairment
provision of $30,131 related to its proved oil and gas properties during 1998.

NOTE 4.    INCOME TAXES

     The financial statement basis of the Partnership's net assets and
liabilities was $172,373 greater than the tax basis at December 31, 2000.

     The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                           2000       1999     1998
                                                        ---------   -------- ---------

                                                                    
    Net income (loss) per statements of operations     $ 140,560    $ 6,232  $ (96,589)
    Depletion and depreciation provisions for tax
     reporting purposes less than amounts for
     financial reporting purposes                         41,011     44,867     91,653
    Impairment of oil and gas properties for
     financial reporting purposes                           -          -        30,131
    Other, net                                              (482)      (178)       454
                                                        ---------   -------- ---------

         Net income per Federal income tax returns      $181,089   $ 50,921   $ 25,649
                                                        =========   ======== =========



NOTE 5.     OIL AND GAS PRODUCING ACTIVITIES

The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:




                                                2000         1999           1998
                                             ---------     --------      ---------

                                                                
     Development costs                       $  7,183      $  4,254      $  8,322
                                             =========     ========      =========

     Capitalized oil and gas properties consist of the following:




                                                          2000           1999
                                                      ----------      ----------
                                                              
     Proved properties:
       Property acquisition costs                    $   210,548     $   210,548
       Completed wells and equipment                   5,134,748       5,127,565
                                                      ----------      ----------

                                                       5,345,296       5,338,113
     Accumulated depletion                            (4,821,914)     (4,776,074)



       Net oil and gas properties                    $   523,382    $    562,039
                                                      ==========      ==========






                                       9
   207



NOTE 6.     RELATED PARTY TRANSACTIONS

     Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                         2000          1999            1998
                                                       --------      --------        --------
                                                                           
    Payment of lease operating and supervision
     charges in accordance with standard industry
     operating agreements                              $ 75,129      $ 61,684        $ 82,817

    Reimbursement of general and administrative
     expenses                                          $ 11,615      $  6,142        $  6,273


     Pioneer USA, EMPL and the Partnership are parties to the Partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 80% and the
remaining portion is owned by former affiliates.

     The costs and revenues of the Partnership are allocated as follows:




                                                         General       Limited
                                                         partners      partners
                                                         --------      --------
                                                                 
   Revenues:
     Proceeds from property dispositions prior to cost
      recovery                                              10%          90%
     All other Partnership revenues                         25%          75%
   Costs and expenses:
     Lease acquisition costs, drilling and completion
      costs and all other costs                             10%          90%
     Operating costs, direct costs and general and
      administrative expenses                               25%          75%


NOTE 7.     OIL AND GAS INFORMATION (UNAUDITED)

     The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.


                                       10
   208





                                                    Oil and NGLs          Gas
                                                       (bbls)            (mcf)
                                                    ------------      ------------

                                                                
    Net proved reserves at January 1, 1998            203,263            321,961
    Revisions                                         (93,478)          (131,045)
    Production                                        (16,033)           (22,439)
                                                    ---------         ----------

    Net proved reserves at December 31, 1998           93,752            168,477
    Revisions                                         118,281            224,790
    Production                                        (13,232)           (19,167)
                                                    ---------         ----------
    Net proved reserves at December 31, 1999          198,801            374,100
    Revisions                                          18,015            (61,237)
    Production                                        (13,921)           (15,864)
                                                    ---------         ----------
    Net proved reserves at December 31, 2000          202,895            296,999
                                                    =========         ==========


     As of December 31, 2000, the estimated present value of future net revenues
of proved reserves, calculated using December 31, 2000 prices of $26.64 per
barrel of oil, $14.08 per barrel of NGLs and $7.91 per mcf of gas, discounted at
10% was approximately $1,416,000 and undiscounted was $2,636,000.

     Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

    The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

    Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.









                                       11
   209





                                              For the years ended December 31,
                                              --------------------------------

                                                2000        1999       1998
                                              ---------  ----------  ---------
                                                      (in thousands)
                                                           
Oil and gas producing activities:
  Future cash inflows                         $  6,624   $   4,915   $  1,020
  Future production costs                       (3,988)     (3,116)      (849)
                                              --------   ---------   --------

                                                 2,636       1,799        171
  10% annual discount factor                    (1,220)       (799)       (47)
                                              --------   ---------   --------

  Standardized measure of discounted future
   net cash flows                             $  1,416   $   1,000   $    124
                                              ========   =========   ========







                                              For the years ended December 31,
                                              --------------------------------

                                                2000        1999       1998
                                              ---------  ----------  ---------
                                                      (in thousands)

                                                           
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs  $ (197)  $    (64)  $     (35)
    Net changes in prices and production costs     530         471       (544)
    Revisions of previous quantity estimates        45         781        (94)
    Accretion of discount                          100          12         76
    Changes in production rates, timing and
      other                                        (62)       (324)       (40)
                                              --------   ---------   --------
    Change in present value of future net
      revenues                                     416         876       (637)
                                              --------   ---------   --------
    Balance, beginning of year                   1,000         124        761
                                                ------     -------     ------

    Balance, end of year                      $  1,416   $   1,000   $    124
                                               =======    ========    =======




NOTE 8.    MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:




                                                2000       1999        1998
                                              --------   --------    --------

                                                            
            Plains Marketing, L.P.              56%         48%         -
            LG&E Natural Marketing, Inc.        13%         17%        19%
            NGTS LLC                            11%         14%         -
            Western Gas Processing               2%          4%        13%
            Genesis Crude Oil, L.P.              4%          1%        43%


     At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
LG&E Natural Marketing, Inc. and NGTS LLC were $26,794, $10,707 and $4,029,
respectively, which are included in the caption "Accounts receivable - oil and
gas sales" in the accompanying Balance Sheet.

     Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.


                                       12
   210



NOTE 9.     PARTNERSHIP AGREEMENT

     The following is a brief summary of the more significant provisions of the
limited partnership agreement:

     General partners - The general partners of the Partnership are Pioneer USA
     and EMPL. Pioneer USA, the managing general partner, has the power and
     authority to manage, control and administer all Partnership affairs. As
     managing general partner and operator of the Partnership's properties, all
     production expenses are incurred by Pioneer USA and billed to the
     Partnership. The majority of the Partnership's oil and gas revenues are
     received directly by the Partnership, however, a portion of the oil and gas
     revenue is initially received by Pioneer USA prior to being paid to the
     Partnership.

     Limited partner liability - The maximum amount of liability of any limited
     partner is the total contributions of such partner plus his share of any
     undistributed profits.

     Initial capital contributions - The limited partners entered into
     subscription agreements for aggregate capital contributions of $5,765,000.
     During 1983, the Partnership received a total of $675,000 from its limited
     partnership in response to an assessment by the managing general partner.
     The general partners are required to contribute amounts equal to 10% of
     Partnership expenditures for lease acquisition, drilling and completion and
     25% of direct, general and administrative and operating expenses.



                                       13
   211

                          PARKER & PARSLEY 81-II, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
  RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 89% to $387,180 for 2000 as
compared to $204,717 in 1999. The increase in revenues resulted from higher
average prices received and a slight increase in production. In 2000, 8,885
barrels of oil, 5,036 barrels of natural gas liquids ("NGLs") and 15,864 mcf of
gas were sold, or 16,565 barrel of oil equivalents ("BOEs"). In 1999, 6,860
barrels of oil, 6,372 barrels of NGLs and 19,167 mcf of gas were sold, or 16,427
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.59, or 76%, from
$16.67 in 1999 to $29.26 in 2000. The average price received per barrel of NGLs
increased $6.89, or 79%, from $8.70 in 1999 to $15.59 in 2000. The average price
received per mcf of gas increased 69% from $1.82 in 1999 to $3.07 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $240 was recognized during 1999 from equipment
credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $249,395 as compared to $200,120
in 1999, an increase of $49,275, or 25%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $189,764 in 2000 and $140,847 in 1999, resulting in a
$48,917 increase, or 35%. The increase was primarily due to additional well
maintenance costs incurred to stimulate well production and higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
40% from $9,864 in 1999 to $13,791 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $11,615 in 2000 and $6,142 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $45,840 in 2000 as compared to $49,409 in 1999, representing a
decrease of $3,569, or 7%. This decrease was primarily due to an 18,828 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices, offset by an increase in oil production of 2,025 barrels for the period
ended December 31, 2000 compared to the same period in 1999.



   212


1999 compared to 1998

The Partnership's 1999 oil and gas revenues decreased 2% to $204,717 from
$209,110 in 1998. The decrease in revenues resulted from a decline in
production, offset by higher average prices received. In 1999, 6,860 barrels of
oil, 6,372 barrels of NGLs and 19,167 mcf of gas were sold, or 16,427 BOEs. In
1998, 9,451 barrels of oil, 6,582 barrels of NGLs and 22,439 mcf of gas were
sold, or 19,773 BOEs.

The average price received per barrel of oil increased $3.51, or 27%, from
$13.16 in 1998 to $16.67 in 1999. The average price received per barrel of NGLs
increased $1.97, or 29%, from $6.73 in 1998 to $8.70 in 1999. The average price
received per mcf of gas increased slightly from $1.80 in 1998 to $1.82 in 1999.

Gain on disposition of assets of $240 was recognized during 1999 from equipment
credits received on one fully depleted well.

Total costs and expenses decreased in 1999 to $200,120 as compared to $307,424
in 1998, a decrease of $107,304, or 35%. The decrease was primarily due to
declines in depletion, production costs and the impairment of oil and gas
properties, offset by an increase in G&A.

Production costs were $140,847 in 1999 and $173,960 in 1998, resulting in a
$33,113 decrease, or 19%. The decrease was due to declines in well maintenance
costs, ad valorem taxes and production taxes.

During this period, G&A increased 25% from $7,867 in 1998 to $9,864 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $6,142 in
1999 and $6,273 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $30,131 related to its oil and gas properties during 1998.

Depletion was $49,409 in 1999 compared to $95,466 in 1998, representing a
decrease of $46,057, or 48%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 59,807 barrels of oil
during 1999 as a result of higher commodity prices, a decline in oil production
of 2,591 barrels for the period ended December 31, 1999 compared to the same
period in 1998 and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum Industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.




   213


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $93,061 during the year
ended December 31, 2000 from 1999. This increase was due to increases in oil and
gas sales receipts of $183,843, offset by increases in production costs paid of
$48,917, G&A expenses paid of $3,927 and working capital of $37,938. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $65,846 to oil and gas receipts and
$117,997 resulted from an increase in production during 2000. The increase in
production costs was primarily due to increased production taxes associated with
higher oil and gas prices and well maintenance costs incurred to stimulate well
production. The increase in G&A was primarily due to higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to upgrades of equipment on various oil and gas properties.

Proceeds from asset dispositions of $690 were received during 1999 for the sale
of equipment on active properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $141,760, of which $38,944 was
distributed to the general partners and $102,816 to the limited partners. In
1999, cash distributions to the partners were $36,945, of which $9,080 was
distributed to the general partners and $27,865 to the limited partners.












   214



                          PARKER & PARSLEY 81-II, LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
  Oil and gas sales                $          $   70,001   $  387,180   $  204,717   $  209,110   $  311,922   $  363,398
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   30,131   $   52,269   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $          $       --   $       --   $       --   $       --   $       --   $    3,289
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $    7,922   $  140,560   $    6,232   $  (96,589)  $    9,511   $  113,519
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $    3,743   $   41,791   $    8,423   $   (5,308)  $   24,620   $   37,637
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $    4,179   $   98,769   $   (2,191)  $  (91,281)  $  (15,109)  $   75,882
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     3.62   $    85.66   $    (1.90)  $   (79.17)  $   (13.10)  $    65.81
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    11.23   $    89.17   $    24.17   $    29.68   $    93.49   $    89.30(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  611,605   $  617,579   $  620,107   $  647,798   $  793,920   $  928,791
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $2.85
     in 1996.



   215

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 82-I, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED         , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS         , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
82-I, Ltd. and supplements the proxy statement/prospectus dated         , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc.,
by which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 82-I, Ltd.:

     o   A table containing:

         --       the aggregate initial investment by the limited partners


         --       the aggregate historical limited partner distributions through
                  July 31, 2001

         --       the merger value attributable to partnership interests of
                  limited partners, excluding Pioneer USA

         --       the merger value per $1,000 limited partner investment

         --       the merger value per $1,000 limited partner investment as a
                  multiple of distributions for the past four quarterly
                  distributions including the distribution in July 2001


         --       the book value per $1,000 limited partner investment as of
                  March 31, 2001 and as of December 31, 2000


         --       the going concern value per $1,000 limited partner investment

         --       the liquidation value per $1,000 limited partner investment


         --       the ordinary tax loss per $1,000 limited partner investment in
                  year of initial investment

     o   Information about:


         --       the legal opinion for the limited partners

         --       the term of the partnership


     o   The partnership's quarterly report on Form 10-Q, including management's
         discussion and analysis of financial condition and results of
         operations, for the three months ended March 31, 2001

     o   The partnership's annual report on Form 10-K, including management's
         discussion and analysis of financial condition and results of
         operations, for the year ended December 31, 2000

     o   Selected historical financial data for the partnership for the three
         months ended March 31, 2001 and 2000 and the five years ended December
         31, 2000


                                      - 1-


   216


                           PARKER & PARSLEY 82-I, LTD.

                         SUPPLEMENTAL INFORMATION TABLE







                                                                                          
Aggregate Initial Investment by the Limited Partners(a)                                      $11,805

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                  $11,639

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer    $   844
USA(a),(b)

Merger Value per $1,000 Limited Partner Investment(b),(c)                                    $ 80.06

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the       2.72 times
past four quarterly distributions including the distribution in July 2001(b),(c)

Book Value per $1,000 Limited Partner Investment:

     --  as of March 31, 2001(c)                                                             $ 22.31

     --  as of December 31, 2000(c)                                                          $ 23.71

Going Concern Value per $1,000 Limited Partner Investment(c),(d)                             $ 72.07

Liquidation Value per $1,000 Limited Partner Investment(c),(e)                               $ 77.68

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment        $   265
(c),(f)


----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.



                                     - 2 -
   217

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001

                          Commission File No. 2-75530A


                           PARKER & PARSLEY 82-1, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                                 75-1825545
          ----------------------------------           ---------------------
           (State or other jurisdiction of                (I.R.S. Employer
           incorporation or organization)              Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas       75039
----------------------------------------------------------------      -------
             (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]




   218



                           PARKER & PARSLEY 82-I, LTD.

                                TABLE OF CONTENTS




                                                                      Page

                                                                      
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000 ....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................    9

            Signatures...............................................   10



                                        2

   219



                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements



                                 BALANCE SHEETS

                                                     March 31,      December 31,
                                                       2001            2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS
                                                              
Current assets:
   Cash                                             $    52,030     $    57,728
   Accounts receivable - oil and gas sales              103,207         109,719
                                                    -----------     -----------
         Total current assets                           155,237         167,447
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
   successful efforts accounting method               9,901,101       9,901,101
Accumulated depletion                                (9,619,512)     (9,613,644)
                                                    -----------     -----------
         Net oil and gas properties                     281,589         287,457
                                                    -----------     -----------
                                                    $   436,826     $   454,904
                                                    ===========     ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable - affiliate                     $    16,407     $    13,712

Partners' capital:
   General partners                                     157,022         161,365
   Limited partners (4,891 interests)                   263,397         279,827
                                                    -----------     -----------
                                                        420,419         441,192
                                                    -----------     -----------
                                                    $   436,826     $   454,904
                                                    ===========     ===========



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

 The accompanying notes are an integral part of these financial statements.

                                        3

   220



                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                   Three months ended
                                                        March 31,
                                                -------------------------
                                                   2001           2000
                                                ----------     ----------

                                                         
Revenues:
  Oil and gas                                   $  216,836     $  172,087
  Interest                                           1,229            973
                                                ----------     ----------
                                                   218,065        173,060
                                                ----------     ----------
Costs and expenses:
  Oil and gas production                            97,986         85,023
  General and administrative                         8,176          5,363
  Depletion                                          5,868          9,057
                                                ----------     ----------
                                                   112,030         99,443
                                                ----------     ----------
Net income                                      $  106,035     $   73,617
                                                ==========     ==========
Allocation of net income:
  General partners                              $   27,134     $   19,763
                                                ==========     ==========
  Limited partners                              $   78,901     $   53,854
                                                ==========     ==========
Net income per limited partnership interest     $    16.13     $    11.01
                                                ==========     ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   221



                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                      General        Limited
                                      partners       partners         Total
                                     ----------     ----------      ----------

                                                           

Balance at January 1, 2001           $  161,365     $  279,827      $  441,192

    Distributions                       (31,477)       (95,331)       (126,808)

    Net income                           27,134         78,901         106,035
                                     ----------     ----------      ----------
Balance at March 31, 2001            $  157,022     $  263,397      $  420,419
                                     ==========     ==========      ==========







         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   222



                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                         Three months ended
                                                              March 31,
                                                       -----------------------
                                                          2001          2000
                                                       ---------     ---------

                                                               
Cash flows from operating activities:
  Net income                                           $ 106,035     $  73,617
  Adjustments to reconcile net income to net
    cash provided by operating activities:
      Depletion                                            5,868         9,057
  Changes in assets and liabilities:
      Accounts receivable                                  6,512       (17,930)
      Accounts payable                                     2,695         1,812
                                                       ---------     ---------
          Net cash provided by operating activities      121,110        66,556
                                                       ---------     ---------
Cash flows used in investing activities:
  Additions to oil and gas properties                         --          (110)

Cash flows used in financing activities:
  Cash distributions to partners                        (126,808)      (61,903)
                                                       ---------     ---------
Net increase (decrease) in cash                           (5,698)        4,543
Cash at beginning of period                               57,728        61,558
                                                       ---------     ---------
Cash at end of period                                  $  52,030     $  66,101
                                                       =========     =========





         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   223



                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley 82-I, Ltd. (the "Partnership") is a limited partnership
organized in 1982 under the laws of the State of Texas.

The  Partnership  engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2. Management's Discussion and Analysis of Financial Condition and Results
        of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 26% to $216,836 for the three
months ended March 31, 2001 as compared to $172,087 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 4,462
barrels of oil, 856 barrels of natural gas liquids ("NGLs") and 13,274 mcf of

                                        7

   224



gas were sold, or 7,530 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 4,433 barrels of oil, 1,810 barrels of NGLs and 12,235 mcf
of gas were sold, or 8,282 BOEs.

The average price received per barrel of oil increased $.79, or 3%, from $27.23
for the three months ended March 31, 2000 to $28.02 for the same period in 2001.
The average price received per barrel of NGLs increased $7.01, or 55%, from
$12.67 for the three months ended March 31, 2000 to $19.68 for the same period
in 2001. The average price received per mcf of gas increased 143%, from $2.33
for the three months ended March 31, 2000 to $5.65 for the same period in 2001.
The market price for oil and gas has been extremely volatile in the past decade,
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $112,030 for the three months ended March
31, 2001 as compared to $99,443 for the same period in 2000, an increase of
$12,587, or 13%. This increase was primarily due to increases in production
costs and general and administrative expenses ("G&A"), offset by a decline in
depletion.

Production costs were $97,986 for the three months ended March 31, 2001 and
$85,023 for the same period in 2000 resulting in a $12,963 increase, or 15%. The
increase was primarily due to additional well maintenance costs incurred to
stimulate well production and higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 52% from $5,363 for the three months ended March 31, 2000 to $8,176
for the same period in 2001 primarily due to a higher percentage of the managing
general partner's G&A being allocated (limited to 3% of oil and gas revenues) as
a result of increased oil and gas revenues and an increase in the accrual for
tax preparation fees.

Depletion was $5,868 for the three months ended March 31, 2001 as compared to
$9,057 for the same period in 2000, a decrease of $3,189, or 35%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $54,554 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to an increase of $45,005 in oil and gas sales receipts and a reduction of
$25,325 in working capital, offset by increases in production costs of $12,963
and G&A expenses of $2,813. The increase in oil and gas receipts resulted from
the increase in commodity prices during 2001 which contributed an additional

                                        8

   225



$57,097 to oil and gas receipts, offset by $12,092 resulting from the decline in
production during 2001 as compared to the same period in 2000. The increase in
production costs was primarily due to additional well maintenance costs incurred
to stimulate well production and increased production taxes associated with
higher oil and gas prices. The increase in G&A was primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues and an
increase in the accrual for tax preparation fees.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $126,808, of which $31,477 was distributed to the general partners and
$95,331 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $61,903, of which $15,492 was distributed to
the general partners and $46,411 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.

                           Part II. Other Information

Item 6.           Exhibits and Reports on Form 8-K

(a)     Exhibits - none

(b)     Reports on Form 8-K - none.


                                        9

   226


                           PARKER & PARSLEY 82-1, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934,  the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 82-1, LTD.

                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 8, 2001                By:      /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       10



   227
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 2-75530A


                           PARKER & PARSLEY 82-I, LTD.
             (Exact name of Registrant as specified in its charter)


                     TEXAS                             75-1825545
        -------------------------------         ----------------------
        (State or other jurisdiction of            (I.R.S. Employer
        incorporation or organization)          Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS        75039
----------------------------------------------------------------      ----------
           (Address of principal executive offices)                   (Zip code)

       Registrant's Telephone Number, including area code: (972) 444-9001

        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($2,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$8,515,000.

       As of March 8, 2001, the number of outstanding limited partnership
                              interests was 4,891.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

   228

                                     PART I

ITEM 1.  BUSINESS

Parker & Parsley 82-I, Ltd. (the "Partnership") is a limited partnership
organized in 1982 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA")
and its co-general partner is P&P Employees 82-I, Ltd. ("EMPL"), a Texas limited
partnership whose general partner is Pioneer USA. Pioneer USA is a wholly-owned
subsidiary of Pioneer Natural Resources Company ("Pioneer"). As of March 8,
2001, the Partnership had 4,891 limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000, approximately 68% and 13% were attributable to sales made
to Plains Marketing, L.P. and GPM Gas Corporation, respectively. Pioneer USA is
of the opinion that the loss of any one purchaser would not have an adverse
effect on its ability to sell its oil, natural gas liquids ("NGLs") and gas
production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.


                                       2
   229

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial liability due to pollution and other
environmental damages. Although the Partnership believes that its business
operations do not impair environmental quality and that its costs of complying
with any applicable environmental regulations are not currently significant, the
Partnership cannot predict what, if any, effect these environmental regulations
may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.  PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental and exploratory oil and gas
prospects located in Texas and New Mexico were acquired by the Partnership,
resulting in the Partnership's participation in the drilling of 34 oil and gas
wells. There were six dry holes from previous periods, two wells plugged and
abandoned and nine wells sold. At December 31, 2000, 17 wells were producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.  LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.


                                       3
   230

                                     PART II

ITEM 5.  MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
           DISTRIBUTIONS

At March 8, 2001, the Partnership had 4,891 outstanding limited partnership
interests held of record by 600 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $229,765 and
$50,502, respectively, were made to the limited partners.

ITEM 6.  SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                   2000           1999           1998           1997         1996
                               ------------   ------------   ------------   ------------   ----------
                                                                            
Operating results:
-----------------
 Oil and gas sales             $    763,858   $    441,997   $    392,883   $    608,207   $  710,173
                               ============   ============   ============   ============   ==========

 Gain on litigation
   settlement, net             $         --   $         --   $         --   $         --   $   43,618
                               ============   ============   ============   ============   ==========

 Impairment of oil and gas
   properties                  $         --   $         --   $    294,610   $    165,201   $    2,277
                               ============   ============   ============   ============   ==========

 Net income (loss)             $    337,729   $     17,320   $   (563,993)  $    (60,847)  $  312,582
                               ============   ============   ============   ============   ==========

 Allocation of net income
   (loss):
     General partners          $     88,128   $     18,135   $    (49,472)  $     31,736   $   92,811
                               ============   ============   ============   ============   ==========

     Limited partners          $    249,601   $       (815)  $   (514,521)  $    (92,583)  $  219,771
                               ============   ============   ============   ============   ==========

 Limited partners' net
   income (loss) per limited
   partnership interest        $      51.03   $       (.17)  $    (105.20)  $     (18.93)  $    44.93
                               ============   ============   ============   ============   ==========

 Limited partners' cash
   distributions per limited
   partnership interest        $      46.98   $      10.33   $      19.57   $      47.31   $    51.40(a)
                               ============   ============   ============   ============   ==========

At year end:
-----------
 Identifiable assets           $    454,904   $    425,107   $    474,528   $  1,158,135   $1,526,765
                               ============   ============   ============   ============   ==========


---------------

(a) Including litigation settlement per limited partnership interest of $6.96 in
    1996.


                                       4
   231

ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
           OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 73% to $763,858 for 2000 as
compared to $441,997 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 17,639
barrels of oil, 6,519 barrels of natural gas liquids ("NGLs") and 45,981 mcf of
gas were sold, or 31,822 barrel of oil equivalents ("BOEs"). In 1999, 17,472
barrels of oil, 6,414 barrels of NGLs and 48,380 mcf of gas were sold, or 31,949
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.78, or 77%, from
$16.61 in 1999 to $29.39 in 2000. The average price received per barrel of NGLs
increased $5.48, or 61%, from $8.96 in 1999 to $14.44 in 2000. The average price
received per mcf of gas increased 69% from $1.95 in 1999 to $3.29 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $431,421 as compared to $427,526
in 1999, an increase of $3,895, or 1%. The increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $378,872 in 2000 and $313,158 in 1999, resulting in an
increase of $65,714, or 21%. The increase was primarily due to additional well
maintenance costs incurred to stimulate well production and higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
39% from $18,932 in 1999 to $26,409 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $22,916 in 2000 and $13,260 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $26,140 in 2000 as compared to $95,436 in 1999, representing a
decrease of $69,296, or 73%. This decrease was primarily due to a 86,555 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 13% to $441,997 from
$392,883 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 17,472 barrels of oil,
6,414 barrels of NGLs and 48,380 mcf of gas were sold, or 31,949 BOEs. In 1998,
19,150 barrels of oil, 6,748 barrels of NGLs and 48,971 mcf of gas were sold, or
34,060 BOEs.


                                       5
   232

The average price received per barrel of oil increased $3.29, or 25%, from
$13.32 in 1998 to $16.61 in 1999. The average price received per barrel of NGLs
increased $1.76, or 24%, from $7.20 in 1998 to $8.96 in 1999. The average price
received per mcf of gas increased 7% from $1.82 in 1998 to $1.95 in 1999.

A gain on disposition of assets of $199 was recognized during 1998 from post
closing adjustments received from the sale of eight oil and gas wells during
1997.

Total costs and expenses decreased in 1999 to $427,526 as compared to $961,319
in 1998, a decrease of $533,793, or 56%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A expenses.

Production costs were $313,158 in 1999 and $336,406 in 1998, resulting in a
$23,248 decrease, or 7%. The decrease was due to declines in well maintenance
costs and ad valorem taxes.

During this period, G&A increased 30% from $14,542 in 1998 to $18,932 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $13,260 in
1999 and $11,786 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $294,610 related to its oil and gas properties during 1998.

Depletion was $95,436 in 1999 compared to $315,761 in 1998, representing a
decrease of $220,325, or 70%. This decrease was the result of an increase in
proved reserves of 168,752 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.


Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact


                                       6
   233

on world oil prices, as have overall natural gas supply and demand fundamentals
on North American natural gas prices. Although the favorable commodity price
environment and stable field service cost environment is expected to continue
during 2001, there is no assurance that commodity prices will not return to a
less favorable level or that field service costs will not escalate in the
future, both of which could negatively impact the Partnership's future results
of operations and cash distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $227,133 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $324,304, offset by increases in production costs paid
of $65,714, G&A expenses paid of $7,477 and working capital of $23,980. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $325,772 to oil and gas receipts,
offset by $1,468 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principle investing activities during 2000 and 1999 were
related to the upgrades of oil and gas equipment on various oil and gas
properties.

Proceeds from asset dispositions of $704 in 1999 were from equipment credits
received on active properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $308,330, of which $78,565 was
distributed to the general partners and $229,765 to the limited partners. In
1999, cash distributions to the partners were $67,767, of which $17,265 was
distributed to the general partners and $50,502 to the limited partners.


                                       7
   234

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


                          INDEX TO FINANCIAL STATEMENTS



                                                                         Page
                                                                         ----
                                                                      
Financial Statements of Parker & Parsley 82-I, Ltd:
 Independent Auditors' Report............................................  9
 Balance Sheets as of December 31, 2000 and 1999......................... 10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................... 11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................... 12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................... 13
 Notes to Financial Statements........................................... 14



                                       8
   235

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 82-I, Ltd.
(A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 82-I, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 82-I, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                     Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                       9
   236

                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                     2000           1999
                                                 -----------    -----------
                                                          
              ASSETS
              ------

Current assets:
 Cash                                            $    57,728    $    61,558
 Accounts receivable - oil and gas sales             109,719         61,533
                                                 -----------    -----------

       Total current assets                          167,447        123,091
                                                 -----------    -----------

Oil and gas properties - at cost, based on the
 successful efforts accounting method              9,901,101      9,889,520
Accumulated depletion                             (9,613,644)    (9,587,504)
                                                 -----------    -----------

       Net oil and gas properties                    287,457        302,016
                                                 -----------    -----------

                                                 $   454,904    $   425,107
                                                 ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
 Accounts payable - affiliate                    $    13,712    $    13,314

Partners' capital:
 General partners                                    161,365        151,802
 Limited partners (4,891 interests)                  279,827        259,991
                                                 -----------    -----------

                                                     441,192        411,793
                                                 -----------    -----------

                                                 $   454,904    $   425,107
                                                 ===========    ===========



   The accompanying notes are an integral part of these financial statements.


                                       10
   237

                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                               2000        1999         1998
                                            ---------   ---------    ---------
                                                            
Revenues:
  Oil and gas                               $ 763,858   $ 441,997    $ 392,883
  Interest                                      5,292       2,849        4,244
  Gain on disposition of assets                    --          --          199
                                            ---------   ---------    ---------

                                              769,150     444,846      397,326
                                            ---------   ---------    ---------

Costs and expenses:
  Oil and gas production                      378,872     313,158      336,406
  General and administrative                   26,409      18,932       14,542
  Impairment of oil and gas properties             --          --      294,610
  Depletion                                    26,140      95,436      315,761
                                            ---------   ---------    ---------

                                              431,421     427,526      961,319
                                            ---------   ---------    ---------

Net income (loss)                           $ 337,729   $  17,320    $(563,993)
                                            =========   =========    =========

Allocation of net income (loss):
  General partners                          $  88,128   $  18,135    $ (49,472)
                                            =========   =========    =========

  Limited partners                          $ 249,601   $    (815)   $(514,521)
                                            =========   =========    =========

Net income (loss) per limited partnership
  interest                                  $   51.03   $    (.17)   $ (105.20)
                                            =========   =========    =========



   The accompanying notes are an integral part of these financial statements.


                                       11
   238

                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                            General          Limited
                                            partners         partners           Total
                                           -----------      -----------      -----------

                                                                    
Partners' capital at January 1, 1998       $   221,119      $   921,541      $ 1,142,660

  Distributions                                (20,715)         (95,712)        (116,427)

  Net loss                                     (49,472)        (514,521)        (563,993)
                                           -----------      -----------      -----------

Partners' capital at December 31, 1998         150,932          311,308          462,240

  Distributions                                (17,265)         (50,502)         (67,767)

  Net income (loss)                             18,135             (815)          17,320
                                           -----------      -----------      -----------

Partners' capital at December 31, 1999         151,802          259,991          411,793

  Distributions                                (78,565)        (229,765)        (308,330)

  Net income                                    88,128          249,601          337,729
                                           -----------      -----------      -----------

Partners' capital at December 31, 2000     $   161,365      $   279,827      $   441,192
                                           ===========      ===========      ===========



   The accompanying notes are an integral part of these financial statements.


                                       12
   239

                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                      2000          1999          1998
                                                    ---------     ---------     ---------
                                                                       
Cash flows from operating activities:
 Net income (loss)                                  $ 337,729     $  17,320     $(563,993)
 Adjustments to reconcile net income (loss) to
   net cash provided by operating activities:
     Impairment of oil and gas properties                  --            --       294,610
     Depletion                                         26,140        95,436       315,761
     Gain on disposition of assets                         --            --          (199)
 Changes in assets and liabilities:
   Accounts receivable                                (48,186)      (24,834)       26,999
   Accounts payable                                       398         1,026        (3,187)
                                                    ---------     ---------     ---------

       Net cash provided by operating activities      316,081        88,948        69,991
                                                    ---------     ---------     ---------

Cash flows from investing activities:
 Additions to oil and gas properties                  (11,581)       (4,754)       (6,820)
 Proceeds from asset dispositions                          --           704        14,397
                                                    ---------     ---------     ---------

       Net cash provided by (used in)
          investing activities                        (11,581)       (4,050)        7,577
                                                    ---------     ---------     ---------

Cash flows used in financing activities:
 Cash distributions to partners                      (308,330)      (67,767)     (116,427)
                                                    ---------     ---------     ---------

Net increase (decrease) in cash                        (3,830)       17,131       (38,859)
Cash at beginning of year                              61,558        44,427        83,286
                                                    ---------     ---------     ---------

Cash at end of year                                 $  57,728     $  61,558     $  44,427
                                                    =========     =========     =========



   The accompanying notes are an integral part of these financial statements.


                                       13
   240

                           PARKER & PARSLEY 82-I, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.  ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 82-I, Ltd. (the "Partnership") is a limited partnership
organized in 1982 under the laws of the State of Texas. The Partnership's
general partners are Pioneer Natural Resources USA, Inc. ("Pioneer USA") and P&P
Employees 82-I, Ltd. ("EMPL"). The Partnership's managing general partner is
Pioneer USA.

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.


                                       14
   241

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.  IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $294,610 related to
its proved oil and gas properties during 1998.


                                       15
   242

NOTE 4.  INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $663,714 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                         2000          1999         1998
                                                      ---------     ---------    ---------

                                                                        
Net income (loss) per statements of operations        $ 337,729     $  17,320    $(563,993)
Depletion and depreciation provisions for
 tax reporting purposes less than amounts for
 financial reporting purposes                            21,746        92,542      312,201
Impairment of oil and gas properties for financial
 reporting purposes                                          --            --      294,610
Loss on disposition of assets                                --            --         (116)
Other, net                                                 (637)           77          786
                                                      ---------     ---------    ---------
        Net income per Federal income tax
          returns                                     $ 358,838     $ 109,939    $  43,488
                                                      =========     =========    =========


NOTE 5.  OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                        2000         1999      1998
                     ---------    ---------    ------

                                      
Development costs    $  11,581    $   4,754    $6,820
                     =========    =========    ======


        Capitalized oil and gas properties consist of the following:



                                        2000            1999
                                    -----------     -----------
                                              
Proved properties:
 Property acquisition costs         $   360,899     $   360,899
 Completed wells and equipment        9,540,202       9,528,621
                                    -----------     -----------

                                      9,901,101       9,889,520
Accumulated depletion                (9,613,644)     (9,587,504)
                                    -----------     -----------

      Net oil and gas properties    $   287,457     $   302,016
                                    ===========     ===========


NOTE 6.  RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related


                                       16
   243

party transactions with the managing general partner during the years ended
December 31:



                                                 2000        1999        1998
                                               --------    --------    --------
                                                              
Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                $162,023    $156,380    $150,391

Reimbursement of general and administrative
  expenses                                     $ 22,916    $ 13,260    $ 11,786


        Pioneer USA, EMPL and the Partnership are parties to the Partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 77.5% and the
remaining portion is owned by former affiliates. In addition, Pioneer USA owned
634 limited partner interests at January 1, 2001.

        The costs and revenues of the Partnership are allocated as follows:



                                                         General       Limited
                                                         partners      partners
                                                         --------      --------
                                                                 
Revenues:
  Proceeds from property dispositions prior to cost
    recovery                                                10%           90%
  All other Partnership revenues                            25%           75%
Costs and expenses:
  Lease acquisition costs, drilling and completion costs    10%           90%
  Operating costs, direct costs and general and
    administrative expenses                                 25%           75%


NOTE 7.  OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                              Oil and NGLs          Gas
                                                 (bbls)            (mcf)
                                              ------------       --------
                                                           
Net proved reserves at January 1, 1998           321,477          448,047
Revisions                                       (230,755)        (305,609)
Production                                       (25,898)         (48,971)
                                                --------         --------



                                       17
   244


                                                           
Net proved reserves at December 31, 1998          64,824           93,467
Revisions                                        280,613          443,568
Production                                       (23,886)         (48,380)
                                                --------         --------

Net proved reserves at December 31, 1999         321,551          488,655
Revisions                                         60,464          362,471
Production                                       (24,158)         (45,981)
                                                --------         --------

Net proved reserves at December 31, 2000         357,857          805,145
                                                ========         ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.55
per barrel of oil, $13.69 per barrel of NGLs and $8.68 per mcf of gas,
discounted at 10% was approximately $3,226,000 and undiscounted was $6,208,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                 For the years ended December 31,
                                                               ------------------------------------
                                                                 2000          1999          1998
                                                               --------      --------      --------

                                                                          (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                          $ 15,230      $  8,078      $    701



                                       18
   245


                                                                                  
  Future production costs                                        (9,022)       (5,386)         (624)
                                                               --------      --------      --------

                                                                  6,208         2,692            77
  10% annual discount factor                                     (2,982)       (1,056)          (11)
                                                               --------      --------      --------

  Standardized measure of discounted future net cash flows     $  3,226      $  1,636      $     66
                                                               ========      ========      ========




                                                      For the years ended December 31,
                                                     ---------------------------------
                                                       2000         1999         1998
                                                     -------      -------      -------
                                                               (in thousands)
                                                                      
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs         $  (385)     $  (128)     $   (56)
  Net changes in prices and production costs           1,448          378         (898)
  Revisions of previous quantity estimates               927        2,018         (164)
  Accretion of discount                                  164            6          118
  Changes in production rates, timing and other         (564)        (704)        (113)
                                                     -------      -------      -------

  Change in present value of future net revenues       1,590        1,570       (1,113)
                                                     -------      -------      -------

  Balance, beginning of year                           1,636           66        1,179
                                                     -------      -------      -------

  Balance, end of year                               $ 3,226      $ 1,636      $    66
                                                     =======      =======      =======


NOTE 8.  MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                               2000    1999    1998
                               ----    ----    ----
                                      
Plains Marketing, L.P.          68%     66%     --
Genesis Crude Oil, L.P.         --      --      65%
GPM Gas Corporation             13%     14%     13%
Western Gas Resources, Inc.      1%      2%     10%


        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and GPM Gas Corporation were $54,651 and $30,037, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.


NOTE 9.  PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        General partners - The general partners of the Partnership are Pioneer
        USA and EMPL.


                                       19
   246
        Pioneer USA, the managing general partner, has the power and authority
        to manage, control and administer all Partnership affairs. As managing
        general partner and operator of the Partnership's properties, all
        production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $9,782,000. During 1985, the Partnership received a total of $1,372,500
        from its limited partners in response to an assessment by the managing
        general partner. Additionally, $650,000 was contributed by the managing
        general partner for limited partnership interests on unpaid assessments
        of which $500,000 was paid in 1985 and $150,000 in 1986. The general
        partners are required to contribute amounts equal to 10% of Partnership
        expenditures for lease acquisition, drilling and completion and 25% of
        direct, general and administrative and operating expenses.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
           FINANCIAL DISCLOSURE

None.


                                       20
   247

                                    PART III

ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                        Age at
                                     December 31,
        Name                             2000                    Position
        ----                             ----                    --------
                                                   
  Scott D. Sheffield                      48             President

  Timothy L. Dove                         44             Executive Vice President, Chief
                                                           Financial Officer and Director

  Dennis E. Fagerstone                    51             Executive Vice President and Director

  Mark L. Withrow                         53             Executive Vice President, General
                                                           Counsel and Director

  Danny Kellum                            46             Executive Vice President - Domestic
                                                           Operations and Director

  Rich Dealy                              34             Vice President and Chief Accounting
                                                           Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts


                                       21
   248

Institute of Technology in 1979 and received his M.B.A. in 1981 from the
University of Chicago. He became Executive Vice President - Business Development
of Pioneer and Pioneer USA in August 1997 and was also appointed a director of
Pioneer USA in August 1997. Mr. Dove assumed the position of Chief Financial
Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr. Dove joined
Parker & Parsley in May 1994 as Vice President - International and was promoted
to Senior Vice President - Business Development in October 1996, in which
position he served until August 1997. Prior to joining Parker & Parsley, Mr.
Dove was employed with Diamond Shamrock Corp., and its successor, Maxus Energy
Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B.S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.


                                       22
   249

ITEM 11.  EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. Under the
Partnership agreement, Pioneer USA pays 8% of the Partnership's acquisition,
drilling and completion costs and 20% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 20% of the
Partnership's revenues.

EMPL is a co-general partner of the Partnership. Under this arrangement, EMPL
pays 2% of the Partnership's acquisition, drilling and completion costs and 5%
of its operating and general and administrative expenses. In return, EMPL is
allocated 5% of the Partnership's revenues. EMPL does not receive any fees or
reimbursements from the Partnership.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)  Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
and EMPL respectively own 80% and 20% of the general partners' interests in the
Partnership. Pioneer USA owned 634 limited partner interests at January 1, 2001.

(b)  Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.


                                       23
   250

ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                  2000         1999         1998
                                                --------     --------     --------

                                                                 
Payment of lease operating and supervision
   charges in accordance with standard
   industry operating agreements                $162,023     $156,380     $150,391

Reimbursement of general and administrative
   expenses                                     $ 22,916     $ 13,260     $ 11,786


Under the limited partnership agreement, the general partners, Pioneer USA and
EMPL, together pay 10% of the Partnership's acquisition, drilling and completion
costs and 25% of its operating and general and administrative expenses. In
return, they are allocated 25% of the Partnership's revenues. Twenty percent of
the general partners' share of costs and revenues is allocated to EMPL and the
remainder is allocated to Pioneer USA. Certain former affiliates of Pioneer USA
are limited partners of EMPL. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Partnership.


                                       24
   251

                                     PART IV


ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)  1.  Financial statements

         The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                  1999 and 1998

                Statements of partners' capital for the years ended December 31,
                  2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                  1999 and 1998

                Notes to financial statements

     2.  Financial statement schedules

         All financial statement schedules have been omitted since the required
         information is in the financial statements or notes thereto, or is not
         applicable nor required.

(b)  Reports on Form 8-K

None.

(c)  Exhibits

     The exhibits listed on the accompanying index to exhibits are filed or
     incorporated by reference as part of this Report.


                                       25
   252

                               S I G N A T U R E S

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                   PARKER & PARSLEY 82-I, LTD.

Dated: March 23, 2001              By:   Pioneer Natural Resources USA, Inc.
                                           Managing General Partner


                                         By:  /s/ Scott D. Sheffield
                                             ---------------------------------
                                             Scott D. Sheffield, President

     Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.


                                                                      
/s/ Scott D. Sheffield            President of Pioneer USA                  March 23, 2001
-----------------------------
Scott D. Sheffield


/s/ Timothy L. Dove               Executive Vice President, Chief           March 23, 2001
-----------------------------     Financial Officer and Director of
Timothy L. Dove                   Pioneer USA


/s/ Dennis E. Fagerstone          Executive Vice President and              March 23, 2001
-----------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow               Executive Vice President, General         March 23, 2001
-----------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                  Executive Vice President - Domestic       March 23, 2001
-----------------------------     Operations and Director of Pioneer
Danny Kellum                      USA


/s/ Rich Dealy                    Vice President and Chief Accounting       March 23, 2001
-----------------------------     Officer of Pioneer USA
Rich Dealy



                                       26
   253

                           PARKER & PARSLEY 82-I, LTD.

                                INDEX TO EXHIBITS


        The following documents are incorporated by reference in response to
Item 14(c):



  Exhibit No.                             Description                              Page
  -----------                             -----------                              ----
                                                                             
       3.1                Agreement of Limited Partnership of Parker                  -
                          & Parsley 82-I, Ltd. incorporated by reference
                          to Exhibit 4(e) of Partnership's Registration
                          Statement on Form S-1 (Registration No.
                          2-75503A), as amended on February 4, 1982,
                          the effective date thereof (hereinafter called,
                          the Partnership's Registration Statement)

       3.2                Amended and Restated Certificate of Limited                 -
                          Partnership of Parker & Parsley 82-I, Ltd.
                          incorporated by reference to Exhibit 3.2 of
                          the Partnership's Annual Report on Form 10-K
                          for the year ended December 31, 1983

       4.1                Form of Subscription Agreement and Power                    -
                          of Attorney incorporated by reference to
                          Exhibit 4(b) of the Partnership's Registration
                          Statement

       4.2                Specimen Certificate of Limited Partnership                 -
                          Interest incorporated by reference to Exhibit
                          4(d) of the Partnership's Registration Statement




                                       27
   254


                           PARKER & PARSLEY 82-I, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                           March 31,                            Years ended December 31,
                                    ---------------------   --------------------------------------------------------------
                                      2001        2000         2000         1999         1998         1997         1996
                                    --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                           
Operating results:
  Oil and gas sales                 $          $  172,087   $  763,858   $  441,997   $  392,883   $  608,207   $  710,173
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                 $     --   $       --   $       --   $       --   $       --   $       --   $   43,618
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
      properties                    $          $       --   $       --   $       --   $  294,610   $  165,201   $    2,277
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                 $          $   73,617   $  337,729   $   17,320   $ (563,993)  $  (60,847)  $  312,582
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
        General partners            $          $   19,763   $   88,128   $   18,135   $  (49,472)  $   31,736   $   92,811
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

        Limited partners            $          $   53,854   $  249,601   $     (815)  $ (514,521)  $  (92,583)  $  219,771
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest            $          $    11.01   $    51.03   $     (.17)  $  (105.20)  $   (18.93)  $    44.93
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest            $          $     9.49   $    46.98   $    10.33   $    19.57   $    47.31   $    51.40(a)
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets               $          $  438,633   $  454,904   $  425,107   $  474,528   $1,158,135   $1,526,765
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $6.96
     in 1996.



   255
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 82-II, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
82-II, Ltd. and supplements the proxy statement/prospectus dated      , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 82-II, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   256
                          PARKER & PARSLEY 82-II, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners (a)                                       $  12,252

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                   $  13,991

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   1,199
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                    $  101.61

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           4.07 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                         $   64.74

          --  as of December 31, 2000 (c)                                                      $   67.39

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                             $   93.48

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                               $   98.65

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     245
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.

                                      -2-

   257


                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 2-75530B


                          PARKER & PARSLEY 82-II, LTD.
             (Exact name of Registrant as specified in its charter)


                  Texas                                 75-1867115
     ----------------------------------           ---------------------
      (State or other jurisdiction of                (I.R.S. Employer
       incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas       75039
----------------------------------------------------------------    ----------
           (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code:  (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]





   258

                          PARKER & PARSLEY 82-II, LTD.


                                TABLE OF CONTENTS




                                                                        Page
                                                                  
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000 ......................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000............................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001.....................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000............................    6

            Notes to Financial Statements..............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations......................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K...........................   10

            Signatures.................................................   11




                                        2

   259



                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                     March 31,     December 31,
                                                       2001             2000
                                                   ------------    ------------
                                                   (Unaudited)
                                                             
                 ASSETS

Current assets:
  Cash                                             $     48,062    $     77,911
  Accounts receivable - oil and gas sales               107,777         107,778
                                                   ------------    ------------
        Total current assets                            155,839         185,689
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                8,307,568       8,305,901
Accumulated depletion                                (7,542,051)     (7,531,290)
                                                   ------------    ------------
        Net oil and gas properties                      765,517         774,611
                                                   ------------    ------------
                                                   $    921,356    $    960,300
                                                   ============    ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $     15,251    $     12,662

Partners' capital:
  General partners                                      112,883         121,968
  Limited partners (6,126 interests)                    793,222         825,670
                                                   ------------    ------------
                                                        906,105         947,638
                                                   ------------    ------------
                                                   $    921,356    $    960,300
                                                   ============    ============




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   260



                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                  Three months ended
                                                       March 31,
                                                -----------------------
                                                   2001         2000
                                                ----------   ----------
                                                       

Revenues:
  Oil and gas                                   $  211,680   $  165,410
  Interest                                           1,399        1,263
                                                ----------   ----------
                                                   213,079      166,673
                                                ----------   ----------
Costs and expenses:
  Oil and gas production                           104,940       74,818
  General and administrative                         7,929        5,159
  Depletion                                         10,761       12,175
                                                ----------   ----------
                                                   123,630       92,152
                                                ----------   ----------
Net income                                      $   89,449   $   74,521
                                                ==========   ==========
Allocation of net income
  General partners                              $   23,721   $   20,457
                                                ==========   ==========
  Limited partners                              $   65,728   $   54,064
                                                ==========   ==========
Net income per limited partnership interest     $    10.73   $     8.83
                                                ==========   ==========




     The financial information included herein has been prepared by the managing
general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        4

   261


                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                       General       Limited
                                       partners      partners       Total
                                      ----------    ----------    ----------
                                                            

Balance at January 1, 2001            $  121,968    $  825,670    $  947,638

    Distributions                        (32,806)      (98,176)     (130,982)

    Net income                            23,721        65,728        89,449
                                      ----------    ----------    ----------

Balance at March 31, 2001             $  112,883    $  793,222    $  906,105
                                      ==========    ==========    ==========



         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5
   262



                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                           Three months ended
                                                                March 31,
                                                        ------------------------
                                                           2001          2000
                                                        ----------    ----------
                                                                

Cash flows from operating activities:
  Net income                                            $   89,449    $   74,521
  Adjustments to reconcile net income to net
     cash provided by operating activities:
       Depletion                                            10,761        12,175
  Changes in assets and liabilities:
       Accounts receivable                                       1        (7,659)
       Accounts payable                                      2,589         1,525
                                                        ----------    ----------
          Net cash provided by operating activities        102,800        80,562
                                                        ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                       (1,667)          (27)

Cash flows used in financing activities:
  Cash distributions to partners                          (130,982)      (81,280)
                                                        ----------    ----------
Net decrease in cash                                       (29,849)         (745)
Cash at beginning of period                                 77,911        91,672
                                                        ----------    ----------
Cash at end of period                                   $   48,062    $   90,927
                                                        ==========    ==========




         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        6

   263
                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 82-II, Ltd. (the "Partnership") is a limited partnership
organized in 1982 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 28% to $211,680 for the three
months ended March 31, 2001 as compared to $165,410 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 4,246
barrels of oil, 1,372 barrels of natural gas liquids ("NGLs") and 11,592 mcf of
gas were sold, or 7,550 barrel of oil equivalents ("BOEs"). For the three months




                                        7

   264



ended March 31, 2000, 4,439 barrels of oil, 2,044 barrels of NGLs and 9,151 mcf
of gas were sold, or 8,008 BOEs.

The average price received per barrel of oil increased $.85, or 3%, from $27.27
for the three months ended March 31, 2000 to $28.12 for the same period in 2001.
The average price received per barrel of NGLs increased $6.36, or 48%, from
$13.18 for the three months ended March 31, 2000 to $19.54 for the same period
in 2001. The average price received per mcf of gas increased 197% from $1.90
during the three months ended March 31, 2000 to $5.65 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $123,630 for the three months ended March
31, 2001 as compared to $92,152 for the same period in 2000, an increase of
$31,478, or 34%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $104,940 for the three months ended March 31, 2001 and
$74,818 for the same period in 2000 resulting in a $30,122 increase, or 40%. The
increase was primarily due to additional well maintenance costs incurred to
stimulate well production and higher production taxes due to increased oil and
gas revenues.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 54% from $5,159 for the three months ended March 31, 2000 to $7,929
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $10,761 for the three months ended March 31, 2001 as compared to
$12,175 for the same period in 2000, a decrease of $1,414, or 12%. This decrease
was primarily due to a decline in oil production of 193 barrels for the three
months ended March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $22,238 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to an increase of $46,406 in oil and gas sales receipts and a reduction of
$8,724 in working capital, offset by increases in production costs of $30,122
and G&A expenses of $2,770. The increase in oil and gas receipts resulted from



                                        8

   265



the increase in commodity prices during 2001 which contributed an additional
$51,185 to oil and gas receipts, offset by $4,779 resulting from the decline in
production during 2001 as compared to the same period in 2000. The increase in
production costs was primarily due to additional well maintenance costs incurred
to stimulate well production and higher production taxes associated with higher
oil and gas prices. The increase in G&A was primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues and an increase in
the accrual for tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 were related to the upgrades of oil and gas equipment on
active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $130,982, of which $32,806 was distributed to the general partners and
$98,176 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $81,280, of which $20,320 was distributed to
the general partners and $60,960 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.



                                        9

   266



                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)     Exhibits - none

(b)     Reports on Form 8-K - none.







                                       10
   267


                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 82-II, LTD.


                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 8, 2001                By:      /s/ Rich Dealy
                                            ------------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer









                                       11



   268
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 2-75530B


                          PARKER & PARSLEY 82-II, LTD.
             (Exact name of Registrant as specified in its charter)

                    TEXAS                                    75-1867115
       -------------------------------                 ----------------------
       (State or other jurisdiction of                    (I.R.S. Employer
       incorporation or organization)                  Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS         75039
----------------------------------------------------------------      ----------
               (Address of principal executive offices)               (Zip code)

       Registrant's Telephone Number, including area code: (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($2,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$11,800,000.

        As of March 8, 2001, the number of outstanding limited partnership
interests was 6,126.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

Parts I and II of this annual report on Form 10-K (the "Report") contain forward
looking statements that involve risks and uncertainties. Accordingly, no
assurances can be given that the actual events and results will not be
materially different than the anticipated results described in the forward
looking statements. See "Item 1. Business" for a description of various factors
that could materially affect the ability of the Partnership to achieve the
anticipated results described in the forward looking statements.

   269

                                     PART I

ITEM 1. BUSINESS

Parker & Parsley 82-II, Ltd. (the "Partnership") is a limited partnership
organized in 1982 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA")
and its co-general partner is P&P Employees 82-II, Ltd. ("EMPL"), a Texas
limited partnership whose general partner is Pioneer USA. Pioneer USA is a
wholly-owned subsidiary of Pioneer Natural Resources Company ("Pioneer"). As of
March 8, 2001, the Partnership had 6,126 limited partnership interests
outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 70% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations. The oil and gas business is
also subject to environmental hazards such as oil spills, gas leaks and


                                       2
   270

ruptures and discharges of toxic substances or gases that could expose the
Partnership to substantial liability due to pollution and other environmental
damages. Although the Partnership believes that its business operations do not
impair environmental quality and that its costs of complying with any applicable
environmental regulations are not currently significant, the Partnership cannot
predict what, if any, effect these environmental regulations may have on its
current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2. PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental and exploratory oil and gas
prospects located in Texas and New Mexico were acquired by the Partnership,
resulting in the Partnership's participation in the drilling of 52 oil and gas
wells. At December 31, 2000, the Partnership had 16 producing oil and gas wells.
Two wells were plugged and abandoned, five wells were dry holes and 29 wells
have been sold.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3. LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.


                                       3
   271
                                     PART II

ITEM 5. MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
          DISTRIBUTIONS

At March 8, 2001, the Partnership had 6,126 outstanding limited partnership
interests held of record by 772 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the general partners, are not required
to meet the Partnership's obligations are distributed to the partners at least
quarterly in accordance with the limited partnership agreement. During the years
ended December 31, 2000 and 1999, distributions of $270,025 and $93,647,
respectively, were made to the limited partners.

ITEM 6. SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                   2000           1999           1998           1997           1996
                                 ----------     ----------     ----------     ----------     ----------
                                                                              

Operating results:
-----------------
  Oil and gas sales              $  730,936     $  477,533     $  379,887     $  598,339     $  732,599
                                 ==========     ==========     ==========     ==========     ==========

  Gain on litigation
   settlement, net               $       --     $       --     $       --     $       --     $   45,027
                                 ==========     ==========     ==========     ==========     ==========

  Impairment of oil and gas
   properties                    $       --     $       --     $   65,229     $  310,732     $       --
                                 ==========     ==========     ==========     ==========     ==========

  Net income (loss)              $  350,536     $  120,353     $ (131,488)    $  (93,386)    $  322,918
                                 ==========     ==========     ==========     ==========     ==========

  Allocation of net income
   (loss):
     General partner             $   94,215     $   38,680     $    2,863     $   30,221     $   98,377
                                 ==========     ==========     ==========     ==========     ==========

     Limited partners            $  256,321     $   81,673     $ (134,351)    $ (123,607)    $  224,541
                                 ==========     ==========     ==========     ==========     ==========

  Limited partners' net
   income (loss) per limited
   partnership interest          $    41.84     $    13.33     $   (21.93)    $   (20.18)    $    36.65
                                 ==========     ==========     ==========     ==========     ==========

  Limited partners' cash
   distributions per limited
   partnership interest          $    44.08     $    15.29     $   (46.67)    $    43.00     $    49.38 (a)
                                 ==========     ==========     ==========     ==========     ==========

At year end:
-----------
  Identifiable assets            $  960,300     $  971,351     $  971,390     $1,456,326     $1,893,741
                                 ==========     ==========     ==========     ==========     ==========


---------------

(a) Including litigation settlement per limited partnership interest of $6.02 in
    1996.


                                       4
   272

ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
          OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 53% to $730,936 for 2000 as
compared to $477,533 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 17,293
barrels of oil, 7,629 barrels of natural gas liquids ("NGLs") and 35,900 mcf of
gas were sold, or 30,905 barrel of oil equivalents ("BOEs"). In 1999, 17,967
barrels of oil, 9,587 barrels of NGLs and 42,858 mcf of gas were sold, or 34,697
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.39, or 73%, from
$17.08 in 1999 to $29.47 in 2000. The average price received per barrel of NGLs
increased $5.21, or 53%, from $9.80 in 1999 to $15.01 in 2000. The average price
received per mcf of gas increased 66% from $1.79 in 1999 to $2.98 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $387,226 as compared to $361,025
in 1999, an increase of $26,201, or 7%. This increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $316,735 in 2000 and $280,719 in 1999, resulting in an
increase of $36,016, or 13%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
28%, from $19,626 in 1999 to $25,120 in 2000 primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $21,928 in 2000 and $14,326 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $45,371 in 2000 as compared to $60,680 in 1999, a decrease of
$15,309, or 25%. This decrease was primarily due to a 21,082 barrels of oil
increase in proved reserves during 2000 as a result of higher commodity prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 26% to $477,533 from
$379,887 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 17,967 barrels of oil,
9,587 barrels of NGLs and 42,858 mcf of gas were sold, or 34,697 BOEs. In 1998,
19,042 barrels of oil, 8,812 barrels of NGLs and 41,862 mcf of gas were sold, or



                                       5
   273

34,831 BOEs.

The average price received per barrel of oil increased $3.94, or 30%, from
$13.14 in 1998 to $17.08 in 1999. The average price received per barrel of NGLs
increased $2.87, or 41%, from $6.93 in 1998 to $9.80 in 1999. The average price
received per mcf of gas increased 9% from $1.64 in 1998 to $1.79 in 1999.

A gain on disposition of assets of $1,281 was recognized during 1998 from post
closing adjustments received from the sale of six oil and gas wells and an
overriding royalty interest in one well during 1997.

Total costs and expenses decreased in 1999 to $361,025 as compared to $523,894
in 1998, a decrease of $162,869, or 31%. The decrease was primarily due to
declines in depletion and the impairment of oil and gas properties, offset by
increases in production costs and G&A expenses.

Production costs were $280,719 in 1999 and $274,382 in 1998, resulting in an
increase of $6,337, or 2%. The increase was primarily due to additional well
maintenance costs incurred to stimulate well production and an increase in
production taxes due to increased oil and gas revenues, offset by a decline in
ad valorem taxes.

During this period, G&A increased 45% from $13,493 in 1998 to $19,626 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $14,326 in
1999 and $11,397 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $65,229 related to its oil and gas properties during 1998.

Depletion was $60,680 in 1999 compared to $170,790 in 1998, a decrease of
$110,110, or 64%. This decrease was the result of an increase in proved reserves
of 182,544 barrels of oil during 1999 as a result of higher commodity prices and
a reduction in the Partnership's net depletable basis in accordance with SFAS
121 during the fourth quarter of 1998.


Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization


                                       6
   274

of Petroleum Exporting Countries ("OPEC") and certain other crude oil exporting
nations announced reductions in their planned export volumes. Those
announcements, together with the enactment of the announced reductions in export
volumes, had a positive impact on world oil prices, as have overall natural gas
supply and demand fundamentals on North American natural gas prices. Although
the favorable commodity price environment and stable field service cost
environment is expected to continue during 2001, there is no assurance that
commodity prices will not return to a less favorable level or that field service
costs will not escalate in the future, both of which could negatively impact the
Partnership's future results of operations and cash distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $202,645 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $256,384, offset by increases in production costs paid
of $36,016, G&A expenses paid of $5,494 and working capital of $12,229. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $326,338 to oil and gas receipts,
offset by $69,954 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds from asset dispositions of $422 in 1999 were from equipment credits
received on active properties. During 1998, proceeds from disposition of assets
of $153,683 were primarily from the sale of six oil and gas wells during 1997.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $361,123, of which $91,098 was
distributed to the general partners and $270,025 to the limited partners. In
1999, cash distributions to the partners were $124,365, of which $30,718 was
distributed to the general partners and $93,647 to the limited partners.


                                       7
   275

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


                          INDEX TO FINANCIAL STATEMENTS



                                                                         Page
                                                                         ----
                                                                      
Financial Statements of Parker & Parsley 82-II, Ltd:
 Independent Auditors' Report............................................  9
 Balance Sheets as of December 31, 2000 and 1999......................... 10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................... 11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................... 12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................... 13
 Notes to Financial Statements........................................... 14



                                       8
   276

                          INDEPENDENT AUDITORS' REPORT


The Partners
Parker & Parsley 82-II, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 82-II, Ltd. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 82-II, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                       9
   277

                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                      2000             1999
                                                   -----------      -----------
                                                              
               ASSETS
               ------

Current assets:
  Cash                                             $    77,911      $    91,672
  Accounts receivable - oil and gas sales              107,778           68,374
                                                   -----------      -----------

         Total current assets                          185,689          160,046
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               8,305,901        8,297,224
Accumulated depletion                               (7,531,290)      (7,485,919)
                                                   -----------      -----------

         Net oil and gas properties                    774,611          811,305
                                                   -----------      -----------

                                                   $   960,300      $   971,351
                                                   ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                     $    12,662      $    13,126

Partners' capital:
  General partners                                     121,968          118,851
  Limited partners (6,126 interests)                   825,670          839,374
                                                   -----------      -----------

                                                       947,638          958,225
                                                   -----------      -----------

                                                   $   960,300      $   971,351
                                                   ===========      ===========



   The accompanying notes are an integral part of these financial statements.


                                       10
   278

                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                             2000          1999          1998
                                           ---------     ---------     ---------

                                                              
Revenues:
  Oil and gas                              $ 730,936     $ 477,533     $ 379,887
  Interest                                     6,826         3,845        11,238
  Gain on disposition of assets                   --            --         1,281
                                           ---------     ---------     ---------

                                             737,762       481,378       392,406
                                           ---------     ---------     ---------

Costs and expenses:
  Oil and gas production                     316,735       280,719       274,382
  General and administrative                  25,120        19,626        13,493
  Impairment of oil and gas properties            --            --        65,229
  Depletion                                   45,371        60,680       170,790
                                           ---------     ---------     ---------

                                             387,226       361,025       523,894
                                           ---------     ---------     ---------

Net income (loss)                          $ 350,536     $ 120,353     $(131,488)
                                           =========     =========     =========

Allocation of net income (loss):
  General partners                         $  94,215     $  38,680     $   2,863
                                           =========     =========     =========

  Limited partners                         $ 256,321     $  81,673     $(134,351)
                                           =========     =========     =========

Net income (loss) per limited
  partnership interest                     $   41.84     $   13.33     $  (21.93)
                                           =========     =========     =========



   The accompanying notes are an integral part of these financial statements.


                                       11
   279

                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                            General          Limited
                                            partners         partners           Total
                                           -----------      -----------      -----------

                                                                    
Partners' capital at January 1, 1998       $   167,998      $ 1,271,605      $ 1,439,603

  Distributions                                (59,972)        (285,906)        (345,878)

  Net income (loss)                              2,863         (134,351)        (131,488)
                                           -----------      -----------      -----------

Partners' capital at December 31, 1998         110,889          851,348          962,237

  Distributions                                (30,718)         (93,647)        (124,365)

  Net income                                    38,680           81,673          120,353
                                           -----------      -----------      -----------

Partners' capital at December 31, 1999         118,851          839,374          958,225

  Distributions                                (91,098)        (270,025)        (361,123)

  Net income                                    94,215          256,321          350,536
                                           -----------      -----------      -----------

Partners' capital at December 31, 2000     $   121,968      $   825,670      $   947,638
                                           ===========      ===========      ===========



   The accompanying notes are an integral part of these financial statements.


                                       12
   280

                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                       2000          1999          1998
                                                     ---------     ---------     ---------
                                                                        
Cash flows from operating activities:
  Net income (loss)                                  $ 350,536     $ 120,353     $(131,488)
  Adjustments to reconcile net income (loss)
    to net cash provided by operating activities:
      Impairment of oil and gas properties                  --            --        65,229
      Depletion                                         45,371        60,680       170,790
      Gain on disposition of assets                         --            --        (1,281)
  Changes in assets and liabilities:
      Accounts receivable                              (39,404)      (31,612)       23,310
      Accounts payable                                    (464)        3,973        (7,570)
                                                     ---------     ---------     ---------

        Net cash provided by operating activities      356,039       153,394       118,990
                                                     ---------     ---------     ---------

Cash flows from investing activities:
  Additions to oil and gas properties                   (8,677)       (2,053)      (13,600)
  Proceeds from asset dispositions                          --           422       153,683
                                                     ---------     ---------     ---------

        Net cash provided by (used in)
          investing activities                          (8,677)       (1,631)      140,083
                                                     ---------     ---------     ---------

Cash flows used in financing activities:
  Cash distributions to partners                      (361,123)     (124,365)     (345,878)
                                                     ---------     ---------     ---------

Net increase (decrease) in cash                        (13,761)       27,398       (86,805)
Cash at beginning of year                               91,672        64,274       151,079
                                                     ---------     ---------     ---------

Cash at end of year                                  $  77,911     $  91,672     $  64,274
                                                     =========     =========     =========



   The accompanying notes are an integral part of these financial statements.


                                       13
   281

                          PARKER & PARSLEY 82-II, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 82-II, Ltd. (the "Partnership") is a limited
partnership organized in 1982 under the laws of the State of Texas. The
Partnership's general partners are Pioneer Natural Resources USA, Inc. ("Pioneer
USA") and P&P Employees 82-II, Ltd. ("EMPL"). The Partnership's managing general
partner is Pioneer USA.

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.


                                       14
   282


        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the


                                       15
   283

Partnership recognized a non-cash impairment provision of $65,229 related to its
proved oil and gas properties during 1998.

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $425,788 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                         2000          1999         1998
                                                      ---------     ---------    ---------

                                                                        
Net income (loss) per statements of operations        $ 350,536     $ 120,353    $(131,488)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                           39,685        55,288      163,319
Impairment of oil and gas properties for financial
  reporting purposes                                         --            --       65,229
Other, net                                                 (932)          209          217
                                                      ---------     ---------    ---------

      Net income per Federal income tax
        returns                                       $ 389,289     $ 175,850    $  97,277
                                                      =========     =========    =========


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                        2000         1999       1998
                     ---------    ---------    -------

                                      
Development costs    $   8,677    $   2,053    $13,600
                     =========    =========    =======


        Capitalized oil and gas properties consist of the following:



                                       2000            1999
                                   -----------     -----------
                                             
Proved properties:
  Property acquisition costs       $   415,980     $   415,980
  Completed wells and equipment      7,889,921       7,881,244
                                   -----------     -----------

                                     8,305,901       8,297,224
Accumulated depletion               (7,531,290)     (7,485,919)
                                   -----------     -----------

  Net oil and gas properties       $   774,611     $   811,305
                                   ===========     ===========



                                       16
   284

NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                 2000        1999        1998
                                               --------    --------    --------
                                                              
Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                $143,855    $139,170    $133,844

Reimbursement of general and administrative
  expenses                                     $ 21,928    $ 14,326    $ 11,397


        Pioneer USA, EMPL and the Partnership are parties to the Partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 83% and the
remaining portion is owned by former affiliates. In addition, Pioneer USA owned
226 limited partner interests at January 1, 2001.

        The costs and revenues of the Partnership are allocated as follows:



                                                          General      Limited
                                                          partners     partners
                                                          --------     --------
                                                                 
Revenues:
  Proceeds from property dispositions prior to cost
    recovery                                                 10%          90%
  All other Partnership revenues                             25%          75%
Costs and expenses:
  Lease acquisition costs, drilling and completion costs     10%          90%
  Operating costs, direct costs and general and
    administrative expenses                                  25%          75%


NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.


                                       17
   285


                                          Oil and NGLs      Gas
                                             (bbls)        (mcf)
                                          ------------   --------

                                                  
Net proved reserves at January 1, 1998       376,355      512,848
Revisions                                   (163,438)    (164,998)
Production                                   (27,854)     (41,862)
                                            --------     --------

Net proved reserves at December 31, 1998     185,063      305,988
Revisions                                    288,622      425,997
Production                                   (27,554)     (42,858)
                                            --------     --------

Net proved reserves at December 31, 1999     446,131      689,127
Revisions                                    (13,008)     (29,574)
Production                                   (24,922)     (35,900)
                                            --------     --------

Net proved reserves at December 31, 2000     408,201      623,653
                                            ========     ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.58
per barrel of oil, $13.60 per barrel of NGLs and $8.05 per mcf of gas,
discounted at 10% was approximately $3,222,000 and undiscounted was $6,505,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.


                                       18
   286


                                                               For the years ended December 31,
                                                              ----------------------------------
                                                                2000         1999         1998
                                                              --------     --------     --------

                                                                         (in thousands)
                                                                               
Oil and gas producing activities:
  Future cash inflows                                         $ 14,233     $ 11,083     $  2,024
  Future production costs                                       (7,728)      (6,439)      (1,464)
                                                              --------     --------     --------

                                                                 6,505        4,644          560
  10% annual discount factor                                    (3,283)      (2,235)        (228)
                                                              --------     --------     --------

  Standardized measure of discounted future net cash flows    $  3,222     $  2,409     $    332
                                                              ========     ========     ========




                                                        For the years ended December 31,
                                                       ---------------------------------
                                                         2000         1999         1998
                                                       -------      -------      -------
                                                                 (in thousands)
                                                                        
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $  (414)     $  (197)     $  (106)
    Net changes in prices and production costs           1,300          807         (871)
    Revisions of previous quantity estimates              (118)       1,768         (241)
    Accretion of discount                                  240           33          147
    Changes in production rates, timing and other         (195)        (334)         (72)
                                                       -------      -------      -------

    Change in present value of future net revenues         813        2,077       (1,143)
                                                       -------      -------      -------

    Balance, beginning of year                           2,409          332        1,475
                                                       -------      -------      -------

    Balance, end of year                               $ 3,222      $ 2,409      $   332
                                                       =======      =======      =======


NOTE 8. MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                            2000        1999         1998
                                          --------    --------     --------
                                                          
        Plains Marketing, L.P.               70%          65%          -
        Genesis Crude Oil, L.P.               -            -          66%
        Western Gas Resources, Inc.           2%           5%         21%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $56,201 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        General partners - The general partners of the Partnership are Pioneer
        USA and EMPL. Pioneer USA, the managing general partner, has the power
        and authority to manage, control


                                       19
   287

        and administer all Partnership affairs. As managing general partner and
        operator of the Partnership's properties, all production expenses are
        incurred by Pioneer USA and billed to the Partnership. The majority of
        the Partnership's oil and gas revenues are received directly by the
        Partnership, however, a portion of the oil and gas revenue is initially
        received by Pioneer USA prior to being paid to the Partnership.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $12,252,000. The general partners are required to contribute amounts
        equal to 10% of Partnership expenditures for lease acquisition, drilling
        and completion and 25% of direct, general and administrative and
        operating expenses.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
         FINANCIAL DISCLOSURE

None.


                                       20
   288

                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                               Age at
                            December 31,
      Name                      2000                      Position
      ----                      ----                      --------
                                           
Scott D. Sheffield               48              President

Timothy L. Dove                  44              Executive Vice President, Chief
                                                   Financial Officer and Director

Dennis E. Fagerstone             51              Executive Vice President and Director

Mark L. Withrow                  53              Executive Vice President, General
                                                   Counsel and Director

Danny Kellum                     46              Executive Vice President - Domestic
                                                   Operations and Director

Rich Dealy                       34              Vice President and Chief Accounting
                                                   Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.


                                       21
   289

        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.


                                       22
   290

ITEM 11. EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. Under the
Partnership agreement, Pioneer USA pays 8% of the Partnership's acquisition,
drilling and completion costs and 20% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 20% of the
Partnership's revenues.

EMPL is a co-general partner of the Partnership. Under this arrangement, EMPL
pays 2% of the Partnership's acquisition, drilling and completion costs and 5%
of its operating and general and administrative expenses. In return, EMPL is
allocated 5% of the Partnership's revenues. EMPL does not receive any fees or
reimbursements from the Partnership.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a) Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
and EMPL respectively own 80% and 20% of the general partners' interests in the
Partnership. Pioneer USA owned 226 limited partner interests at January 1, 2001.

(b) Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.


                                       23
   291

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the general partners during the years ended
December 31:



                                                     2000         1999         1998
                                                   ---------    ---------    --------
                                                                    
   Payment of lease operating and supervision
     charges in accordance with standard
     industry operating agreements                 $ 143,855    $ 139,170    $133,844

   Reimbursement of general and administrative
     expenses                                      $  21,928    $  14,326    $ 11,397


Under the limited partnership agreement, the general partners, Pioneer USA and
EMPL, together pay 10% of the Partnership's acquisition, drilling and completion
costs and 25% of its operating and general and administrative expenses. In
return, they are allocated 25% of the Partnership's revenues. Twenty percent of
the general partner's share of costs and revenues is allocated to EMPL and the
remainder is allocated to Pioneer USA. Certain former affiliates of the managing
general partner are limited partners of EMPL. Also, see Notes 6 and 9 of Notes
to Financial Statements included in "Item 8. Financial Statements and
Supplementary Data", regarding the Partnership's participation with the managing
general partner in oil and gas activities of the Partnership.


                                       24
   292

                                     PART IV


ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                  1999 and 1998

                Statements of partners' capital for the years ended December 31,
                  2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                  1999 and 1998

                Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.


                                       25
   293

                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 82-II, LTD.

Dated: March 23, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                --------------------------------
                                                Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 23, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 23, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 23, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 23, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 23, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 23, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy



                                       26
   294

                          PARKER & PARSLEY 82-II, LTD.

                                INDEX TO EXHIBITS

        The following documents are incorporated by reference in response to
Item 14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----
                                                                           
       3.1                Agreement of Limited Partnership of                       -
                          Parker & Parsley 82-II, Ltd. incorporated
                          by reference to Exhibit 4(e) of Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 2-75503B), as amended
                          on February 4, 1982, the effective date
                          thereof (hereinafter called, the Partnership's
                          Registration Statement)

       3.2                Amended and Restated Certificate of                       -
                          Limited Partnership of Parker & Parsley
                          82-II, Ltd. incorporated by reference to
                          Exhibit 3.2 of the Partnership's Annual
                          Report on Form 10-K for the year ended
                          December 31, 1983

       4.1                Form of Subscription Agreement and Power                  -
                          of Attorney incorporated by reference to
                          Exhibit 4(b) of the Partnership's Registration
                          Statement

       4.2                Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit
                          4(d) of the Partnership's Registration Statement




                                       27
   295

                          PARKER & PARSLEY 82-II, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                       Three months
                                           ended
                                         March 31,                              Years ended December 31,
                                    ---------------------   --------------------------------------------------------------
                                      2001        2000         2000         1999         1998         1997          1996
                                    --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                           

Operating results:
  Oil and gas sales                 $          $  165,410   $  730,936   $  477,533   $  379,887   $  598,339   $  732,599
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                 $     --   $       --   $       --   $       --   $       --   $       --   $   45,027
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
    properties                      $          $       --   $       --   $       --   $   65,229   $  310,732   $       --
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                 $          $   74,521   $  350,536   $  120,353   $ (131,488)  $  (93,386)  $  322,918
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
        General partner             $          $   20,457   $   94,215   $   38,680   $    2,863   $   30,221   $   98,377
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

        Limited partners            $          $   54,064   $  256,321   $   81,673   $ (134,351)  $ (123,607)  $  224,541
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest            $          $     8.83   $    41.84   $    13.33   $   (21.93)  $   (20.18)  $    36.65
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest            $          $     9.95   $    44.08   $    15.29   $   (46.67)  $    43.00   $    49.38(a)
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets               $          $  966,117   $  960,300   $  971,351   $  971,390   $1,456,326   $1,893,741
                                    ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $6.02
     in 1996.


   296
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 82-III, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
82-III, Ltd. and supplements the proxy statement/prospectus dated       , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 82-III, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-
   297
                          PARKER & PARSLEY 82-III, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $   6,882

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   6,781

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $     788
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  121.72

Merger Value per $1,000 Limited Partner  Investment as a Multiple of Distributions for the         3.16 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $   52.89

          --  as of December 31, 2000 (c)                                                     $   55.84

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  111.21

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  118.08

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     220
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.

                                      -2-

   298

                          PARKER & PARSLEY 82-III, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   299



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS







                                                     March 31,      December 31,
                                                        2001            2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS

                                                              
Current assets:
  Cash                                              $    42,470     $    46,188
  Accounts receivable - oil and gas sales                55,252          69,903
                                                    -----------     -----------
        Total current assets                             97,722         116,091
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,970,397       5,970,397
Accumulated depletion                                (5,640,312)     (5,634,468)
                                                    -----------     -----------
        Net oil and gas properties                      330,085         335,929
                                                    -----------     -----------
                                                    $   427,807     $   452,020
                                                    ===========     ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $    11,823     $     9,780

Partners' capital:
  General partners                                       52,014          57,956
  Limited partners (3,441 interests)                    363,970         384,284
                                                    -----------     -----------
                                                        415,984         442,240
                                                    -----------     -----------
                                                    $   427,807     $   452,020
                                                    ===========     ===========





  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2

   300



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)







                                                         Three months ended
                                                              March 31,
                                                     --------------------------
                                                        2001            2000
                                                     ----------      ----------
                                                               
Revenues:
  Oil and gas                                        $  141,285      $  136,330
  Interest                                                  893             805
                                                     ----------      ----------
                                                        142,178         137,135
                                                     ----------      ----------
Costs and expenses:
  Oil and gas production                                 62,799          52,005
  General and administrative                              5,510           4,182
  Depletion                                               5,844           6,419
                                                     ----------      ----------
                                                         74,153          62,606
                                                     ----------      ----------
Net income                                           $   68,025      $   74,529
                                                     ==========      ==========
Allocation of net income:
  General partners                                   $   17,628      $   19,595
                                                     ==========      ==========
  Limited partners                                   $   50,397      $   54,934
                                                     ==========      ==========
Net income per limited partnership interest          $    14.65      $    15.96
                                                     ==========      ==========



         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   301



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                        General        Limited
                                        partners       partners         Total
                                       ----------     ----------     ----------

                                                            
Balance at January 1, 2001             $   57,956     $  384,284     $  442,240

    Distributions                         (23,570)       (70,711)       (94,281)

    Net income                             17,628         50,397         68,025
                                       ----------     ----------     ----------

Balance at March 31, 2001              $   52,014     $  363,970     $  415,984
                                       ==========     ==========     ==========







         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        4


   302



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)







                                                         Three months ended
                                                              March 31,
                                                      -------------------------
                                                         2001           2000
                                                      ----------     ----------
                                                               
Cash flows from operating activities:
  Net income                                          $   68,025     $   74,529
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                           5,844          6,419
  Changes in assets and liabilities:
       Accounts receivable                                14,651         (6,362)
       Accounts payable                                    2,043            649
                                                      ----------     ----------
         Net cash provided by operating activities        90,563         75,235
                                                      ----------     ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                         --            (27)

Cash flows used in financing activities:
  Cash distributions to partners                         (94,281)       (68,363)
                                                      ----------     ----------
Net increase (decrease) in cash                           (3,718)         6,845
Cash at beginning of period                               46,188         53,335
                                                      ----------     ----------
Cash at end of period                                 $   42,470     $   60,180
                                                      ==========     ==========





         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5

   303



                         PARKER & PARSLEY 82-III, LTD.
                         (A Texas Limited Partnership)

                         NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                  (Unaudited)


Note 1.   Organization and nature of operations

Parker & Parsley 82-III, Ltd. (the "Partnership") is a Texas limited partnership
organized in 1982 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.   Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
  Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 4% to $141,285 for the three
months ended March 31, 2001 as compared to $136,330 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 3,578
barrels of oil, 622 barrels of natural gas liquids ("NGLs") and 5,196 mcf of gas
were sold, or 5,066 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 3,738 barrels of oil, 1,877 barrels of NGLs and 6,304 mcf
of gas were sold, or 6,666 BOEs.

                                       6


   304




The average price received per barrel of oil increased $.94, or 3%, from $27.64
for the three months ended March 31, 2000 to $28.58 for the same period in 2001.
The average price received per barrel of NGLs increased $4.69, or 38%, from
$12.20 for the three months ended March 31, 2000 to $16.89 for the same period
in 2001. The average price received per mcf of gas increased 243% from $1.60
during the three months ended March 31, 2000 to $5.49 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $74,153 for the three months ended March
31, 2001 as compared to $62,606 for the same period in 2000, an increase of
$11,547, or 18%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $62,799 for the three months ended March 31, 2001 and
$52,005 for the same period in 2000 resulting in a $10,794 increase, or 21%. The
increase was primarily due to additional well maintenance costs incurred to
stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 32% from $4,182 for the three months ended March 31, 2000 to $5,510
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $5,844 for the three months ended March 31, 2001 as compared to
$6,419 for the same period in 2000, a decrease of $575, or 9%. This decrease was
primarily due to positive revisions to proved reserves during the three months
ended March 31, 2001 as a result of higher commodity prices and a decline in oil
production of 160 barrels for the three months ended March 31, 2001 as compared
to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $15,328 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to a reduction in working capital of $22,407 and an increase in
oil and gas sales receipts of $5,043, offset by increases in production costs of
$10,794 and G&A expenses of $1,328. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an


                                       7

   305


additional $36,894 to oil and gas receipts, offset by $31,851 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to additional well maintenance
costs incurred to stimulate well production. The increase in G&A was primarily
due to a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $94,281, of which $23,570 was distributed to the general partners and
$70,711 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $68,363, of which $16,801 was distributed to
the general partners and $51,562 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy  statement/prospectus  with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.

                                       8


   306




                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   307



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 82-III, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 82-III, Ltd. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 82-III, Ltd.
as of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                           Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   308



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31






                                                          2000        1999
                                                        -------     -------
           ASSETS

                                                           
Current assets:
  Cash                                                $  46,188   $  53,335
  Accounts receivable  - oil and gas sales               69,903      47,611
                                                        -------     -------

      Total current assets                              116,091     100,946
                                                        -------     -------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,970,397   5,967,913
Accumulated depletion                                (5,634,468) (5,611,986)

      Net oil and gas properties                        335,929     355,927
                                                        -------     -------

                                                      $ 452,020   $ 456,873
                                                       ========    ========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                        $   9,780   $  11,302

Partners' capital:
  General partners                                       57,956      54,214
  Limited partners (3,441 interests)                    384,284     391,357
                                                        -------     -------

                                                        442,240     445,571

                                                      $ 452,020   $ 456,873
                                                       ========    ========



   The accompanying notes are an integral part of these financial statements.



                                       3
   309



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                              2000        1999       1998
                                           ---------    --------   ---------

                                                          
Revenues:
  Oil and gas                             $ 562,399   $ 340,246  $  253,873
  Interest                                    4,310       2,124       3,120
  Gain on disposition of assets                 -         1,922         634
                                            -------     ------     --------

                                            566,709     344,292     257,627
                                            -------     ------     --------

Costs and expenses:
  Oil and gas production                    222,803     198,571     202,485
  General and administrative                 19,194      14,161       9,538
  Impairment of oil and gas properties          -           -       277,671
  Depletion                                  22,482      46,605     252,951
                                            -------      ------    --------

                                            264,479     259,337     742,645
                                            -------     -------    --------

Net income (loss)                         $ 302,230   $  84,955  $ (485,018)
                                            =======      ======    ========

Allocation of net income (loss):
  General partners                        $  78,705   $ 27,431   $  (41,756)
                                            =======     ======     ========

  Limited partners                        $ 223,525   $ 57,524   $ (443,262)
                                            =======     ======     ========

Net income (loss) per limited
  partnership interest                     $  64.96    $ 16.72   $  (128.82)
                                            =======     ======     ========






   The accompanying notes are an integral part of these financial statements.



                                       4
   310



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                            General      Limited
                                            partners     partners     Total
                                           ---------    ----------  ---------




                                                       
Partners' capital at January 1, 1998      $ 106,887  $ 9 13,918 $ 1,020,805

   Distributions                            (16,245)    (70,235)    (86,480)

   Net loss                                 (41,756)   (443,262)   (485,018)
                                           --------    --------   ---------

Partners' capital at December 31, 1998       48,886     400,421     449,307

   Distributions                            (22,103)    (66,588)    (88,691)

   Net income                                27,431      57,524      84,955
                                           --------    --------   ---------

Partners' capital at December 31, 1999       54,214     391,357     445,571

   Distributions                            (74,963)   (230,598)   (305,561)

   Net income                                78,705     223,525     302,230
                                           --------    --------   ---------

Partners' capital at December 31, 2000    $  57,956  $  384,284  $  442,240
                                           ========    ========   =========



   The accompanying notes are an integral part of these financial statements.



                                       5
   311



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                     2000         1999        1998
                                                   --------     --------    ---------

                                                                 
Cash flows from operating activities:
  Net income (loss)                               $ 302,230   $  84,955   $ (485,018)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Gain on disposition of assets                    -         (1,922)        (634)
      Impairment of oil and gas properties             -           -         277,671
      Depletion                                      22,482      46,605      252,951
    Changes in assets and liabilities:
      Accounts receivable                           (22,292)    (24,579)      19,893
      Accounts payable                               (1,522)      5,081       (6,865)
                                                   --------     --------    ---------


        Net cash provided by operating activities   300,898     110,140       57,998
                                                   --------     --------    ---------
Cash flows from investing activities:
  Additions to oil and gas properties                (2,484)     (1,281)      (4,114)
  Proceeds from disposition of assets                   -         2,415       23,382
                                                   --------     --------    ---------

        Net cash provided by (used in)
          investing activities                       (2,484)      1,134       19,268
                                                   --------     --------    ---------

Cash flows used in financing activities:
  Cash distributions to partners                   (305,561)    (88,691)     (86,480)
                                                   --------     --------    ---------

Net increase (decrease) in cash                      (7,147)     22,583       (9,214)
Cash at beginning of year                            53,335      30,752       39,966
                                                   --------     --------    ---------
Cash at end of year                               $  46,188    $ 53,335    $  30,752
                                                   ========     ========    =========




  The accompanying notes are an integral part of these financial statements.



                                       6
   312



                          PARKER & PARSLEY 82-III, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.     ORGANIZATION AND NATURE OF OPERATIONS

     Parker & Parsley 82-III, Ltd. (the "Partnership") is a Texas limited
partnership organized in 1982 under the laws of the State of Texas.  The
Partnership's general partners are Pioneer Natural Resources USA, Inc.
("Pioneer USA") and P&P Employees 82-III, Ltd. ("EMPL"). The Partnership's
managing general partner is Pioneer USA.

     The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.     SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

     A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

     Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

     Impairment of long-lived assets - In accordance with Statement of Financial
Accounting Standards No. 121, "Accounting for the Impairment of Long-Lived
Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

     Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

                                       7
   313

     Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

     Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

     Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

     General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

     Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

     Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

     Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved

                                       8
   314

in the industry. As a result, the Partnership recognized a non-cash impairment
provision of $277,671 related to its proved oil and gas properties during 1998.

NOTE 4.    INCOME TAXES

     The financial statement basis of the Partnership's net assets and
liabilities was $410,896 less than the tax basis at December 31, 2000.

     The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                            2000         1999            1998
                                                          --------     -------         -------

                                                                           
   Net income (loss) per statements of operations       $ 302,230    $ 84,955       $ (485,018)
   Depletion and depreciation provisions for tax
     reporting purposes less than amounts for financial
     reporting purposes                                    18,732      42,255          245,110
   Impairment of oil and gas properties for financial
     reporting purposes                                      -           -             277,671
   Other, net                                                (570)     (1,597)             787
                                                         --------     -------         --------

         Net income per Federal income tax returns      $ 320,392   $ 125,613       $   38,550
                                                         ========     =======         ========


NOTE 5.     OIL AND GAS PRODUCING ACTIVITIES

     The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:




                                            2000         1999        1998
                                           -------      ------     -------
                                                         
   Development costs                      $  2,484     $ 1,281    $  4,114
                                           =======      ======     =======


   Capitalized oil and gas properties consist of the following:




                                                         2000            1999
                                                      ---------       ----------
                                                             
   Proved properties:
     Property acquisition costs                    $    348,798     $   348,798
     Completed wells and equipment                    5,621,599       5,619,115
                                                     ----------     -----------
                                                      5,970,397       5,967,913
   Accumulated depletion                             (5,634,468)     (5,611,986)
                                                     ----------     -----------
        Net oil and gas properties                  $   335,929     $   355,927
                                                     ==========     ===========





                                       9
   315


NOTE 6.     RELATED PARTY TRANSACTIONS

     Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                             2000       1999        1998
                                                            -------    -------    --------
                                                                         
    Payment of lease operating and supervision
     charges in accordance with standard industry
     operating agreements                                  $105,725    $102,247   $ 97,602

    Reimbursement of general and administrative
     expenses                                               $16,872     $10,207   $  7,802



    Pioneer USA, EMPL and the Partnership are parties to the Partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 81% and the
remaining portion is owned by former affiliates. Pioneer USA owned 205.34
limited partner interests at January 1, 2001.

    The costs and revenues of the Partnership are allocated as follows:




                                                                     General       Limited
                                                                     partners      partners
                                                                     --------      --------

                                                                             
   Revenues:
     Proceeds from property dispositions prior to cost
       recovery                                                        10%            90%
     All other Partnership revenues                                    25%            75%
   Costs and expenses:
     Lease acquisition costs, drilling and completion costs            10%            90%
     Operating costs, direct costs and general and
       administrative expenses                                         25%            75%


NOTE 7.     OIL AND GAS INFORMATION (UNAUDITED)

     The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       10
   316



                                                    Oil and NGLs          Gas
                                                       (bbls)            (mcf)
                                                    ------------      ------------


                                                                
   Net proved reserves at January 1, 1998             290,644            256,851
   Revisions                                         (204,881)

   Production                                         (19,540)           (17,680)
                                                    ---------           --------

   Net proved reserves at December 31, 1998            66,223             74,429
   Revisions                                                             243,433
312,763
   Production                                         (20,801)           (23,061)
                                                    ---------             ------

   Net proved reserves at December 31, 1999           288,855            364,131
   Revisions                                           42,883            (44,362)
   Production                                         (20,646)           (21,480)
                                                    ---------             ------

   Net proved reserves at December 31, 2000           311,092            298,289
                                                    =========           ========


     As of December 31, 2000, the estimated present value of future net revenues
of proved reserves, calculated using December 31, 2000 prices of $26.64 per
barrel of oil, $13.66 per barrel of NGLs and $7.61 per mcf of gas, discounted at
10% was approximately $2,053,000 and undiscounted was $3,888,000.

     Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

    The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

    Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.


                                       11
   317








                                                For the years ended December 31,
                                                --------------------------------
                                                 2000         1999       1998
                                                ------      -------     ------
                                                           (in thousands)
                                                           
Oil and gas producing activities:
  Future cash inflows                         $  9,373   $   7,135   $    709
  Future production costs                       (5,485)     (4,540)      (606)
                                                ------     -------     ------

                                                 3,888       2,595        103
  10% annual discount factor                    (1,835)     (1,113)       (26)
                                                ------     -------     ------

  Standardized measure of discounted
    future net cash flows                     $  2,053   $   1,482   $     77
                                                ======     =======     ======






                                                For the years ended December 31,
                                                --------------------------------
                                                 2000         1999       1998
                                                ------      -------     ------
                                                           (in thousands)
                                                              


  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs$     (340)  $    (141)  $    (51)
    Net changes in prices and production costs       711         355       (718)
    Revisions of previous quantity estimates         219       1,650       (182)
    Accretion of discount                            148           8        102
    Changes in production rates, timing and other   (167)       (467)       (96)

    Change in present value of future
      net revenues                                   571       1,405       (945)

    Balance, beginning of year                     1,482          77      1,022
                                                  ------     -------     ------

    Balance, end of year                        $  2,053   $   1,482   $     77
                                                 =======    ========    =======


NOTE 8.    MAJOR CUSTOMERS

  The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:




                                                2000        1999       1998
                                              --------    --------   --------

                                                              
            Plains Marketing, L.P.              60%         56%          -
            TEPPCO Crude Oil LLC                14%         15%          -
  Genesis Crude Oil, L.P.                         -           -        77%


     At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and TEPPCO Crude Oil LLC were $31,458 and $4,158, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

     Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.     PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:


     General partners - The general partners of the Partnership are Pioneer USA
     and EMPL. Pioneer USA, the managing general partner, has the power and
     authority to manage, control and administer all Partnership affairs. As
     managing general partner and operator of the Partnership's properties, all
     production expenses are incurred by Pioneer USA and billed to the
     Partnership. The majority of the Partnership's oil and gas revenues are
     received directly

                                       12
   318

     by the Partnership, however, a portion of the oil and gas
     revenue is initially received by Pioneer USA prior to being paid to the
     Partnership.

     Limited partner liability - The maximum amount of liability of any limited
     partner is the total contributions of such partner plus his share of any
     undistributed profits.

     Initial capital contributions - The limited partners entered into
     subscription agreements for aggregate capital contributions of $6,882,000.
     The general partners are required to contribute amounts equal to 10% of
     Partnership expenditures for lease acquisition, drilling and completion and
     25% of direct, general and administrative and operating expenses.




                                       13
   319

                          PARKER & PARSLEY 82-III, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 65% to $562,399 for 2000 as
compared to $340,246 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 14,019
barrels of oil, 6,627 barrels of natural gas liquids ("NGLs") and 21,480 mcf of
gas were sold, or 24,226 barrel of oil equivalents ("BOEs"). In 1999, 14,043
barrels of oil, 6,758 barrels of NGLs and 23,061 mcf of gas were sold, or 24,645
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.54, or 73%, from
$17.13 in 1999 to $29.67 in 2000. The average price received per barrel of NGLs
increased $4.73, or 52%, from $9.13 in 1999 to $13.86 in 2000. The average price
received per mcf of gas increased 54% from $1.65 in 1999 to $2.54 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $1,922 was recognized during 1999 from
equipment credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $264,479 as compared to $259,337
in 1999, an increase of $5,142, or 2%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $222,803 in 2000 and $198,571 in 1999, resulting in a
$24,232 increase, or 12%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
36% from $14,161 in 1999 to $19,194 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $16,872 in 2000 and $10,207 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $22,482 in 2000 as compared to $46,605 in 1999, representing a
decrease of $24,123, or 52%. This decrease primarily due to a 36,746 barrels of
oil increase in proved reserves during 2000 as a result of higher commodity
prices.




   320


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 34% to $340,246 from
$253,873 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production. In 1999, 14,043 barrels of oil, 6,758
barrels of NGLs and 23,061 mcf of gas were sold, or 24,645 BOEs. In 1998, 14,727
barrels of oil, 4,813 barrels of NGLs and 17,680 mcf of gas were sold, or 22,487
BOEs.

The average price received per barrel of oil increased $3.82, or 29%, from
$13.31 in 1998 to $17.13 in 1999. The average price received per barrel of NGLs
increased $2.71, or 42%, from $6.42 in 1998 to $9.13 in 1999. The average price
received per mcf of gas increased 8% from $1.53 in 1998 to $1.65 in 1999.

A gain on disposition of assets of $1,922 and $634 was recognized during 1999
and 1998 from salvage value received on various asset dispositions.

Total costs and expenses decreased in 1999 to $259,337 as compared to $742,645
in 1998, a decrease of $483,308, or 65%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $198,571 in 1999 and $202,485 in 1998, resulting in a
$3,914 decrease, or 2%. The decrease was due to declines in workover costs and
ad valorem taxes, offset by an increase in production taxes due to increase oil
and gas sales.

During this period, G&A increased 48% from $9,538 in 1998 to $14,161 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $10,207 in
1999 and $7,802 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $277,671 related to its oil and gas properties during 1998.

Depletion was $46,605 in 1999 compared to $252,951 in 1998, representing a
decrease of $206,346, or 82%. This decrease was the result of an increase in
proved reserves of 164,606 barrels of oil during 2000 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.




   321


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $190,758 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $224,339, offset by increases in production costs paid
of $24,233, G&A expenses paid of $5,032 and working capital of $4,316. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $230,886 to oil and gas receipts,
offset by $6,547 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs
incurred to stimulate well production. The increase in G&A was primarily due to
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to upgrades of equipment on various oil and gas properties.

Proceeds from disposition of assets of $2,415 were recognized during 1999 from
salvage value received on disposition of equipment primarily on one oil and gas
well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $305,561, of which $74,963 was
distributed to the general partners and $230,598 to the limited partners. In
1999, cash distributions to the partners were $88,691, of which $22,103 was
distributed to the general partners and $66,588 to the limited partners.













   322



                          PARKER & PARSLEY 82-III, LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  136,330   $  562,399   $  340,246   $  253,873   $  456,184   $  542,331
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  277,671   $  126,140   $    5,776
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $          $       --   $       --   $       --   $       --   $       --   $   36,644
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   74,529   $  302,230   $   84,955   $ (485,018)  $  (87,890)  $  197,417
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $   19,595   $   78,705   $   27,431   $  (41,756)  $   14,576   $   64,259
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   54,934   $  223,525   $   57,524   $ (443,262)  $ (102,466)  $  133,158
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    15.96   $    64.96   $    16.72   $  (128.82)  $   (29.78)  $    38.70
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    14.98   $    67.01   $    19.35   $    20.41   $    43.29   $    49.15(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  463,688   $  452,020   $  456,873   $  455,528   $1,033,891   $1,323,367
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


---------

(a)  Including litigation settlement per limited partnership interest of $10.65
     in 1996.



   323
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 83-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
83-A, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 83-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-

   324
                           PARKER & PARSLEY 83-A, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $  19,505

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $  25,908

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   2,663
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  141.43

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.42 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          -- as of March 31, 2001 (c)                                                         $   73.55

          -- as of December 31, 2000 (c)                                                      $   76.56

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  130.10

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  137.31

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     275
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.

                                     -2-
   325

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 2-81398A


                           PARKER & PARSLEY 83-A, LTD.
             (Exact name of Registrant as specified in its charter)


                        Texas                               75-1891384
          -----------------------------------          ---------------------
           (State or other jurisdiction of                (I.R.S. Employer
           incorporation or organization)              Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
           (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                         if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]






   326



                           PARKER & PARSLEY 83-A, LTD.

                                TABLE OF CONTENTS



                                                                        Page

                                                                       
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000 .....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000...........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001....................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000...........................    6

            Notes to Financial Statements.............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K..........................    9

            Signatures................................................   10



                                        2

   327



                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,     December 31,
                                                       2001            2000
                                                   ------------    ------------
                                                   (Unaudited)

                                                             
                      ASSETS

Current assets:
  Cash                                              $   132,382     $   169,055
  Accounts receivable - oil and gas sales               264,614         279,239
                                                    -----------     -----------
          Total current assets                          396,996         448,294
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method               16,902,945      16,901,194
Accumulated depletion                               (15,642,811)    (15,622,262)
                                                    -----------     -----------
          Net oil and gas properties                  1,260,134       1,278,932
                                                    -----------     -----------
                                                    $ 1,657,130     $ 1,727,226
                                                    ===========     ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $    38,712     $    33,783

Partners' capital:
  General partners                                      183,832         200,131
  Limited partners (19,505 interests)                 1,434,586       1,493,312
                                                    -----------     -----------
                                                      1,618,418       1,693,443
                                                    -----------     -----------
                                                    $ 1,657,130     $ 1,727,226
                                                    ===========     ===========




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   328



                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                      Three months ended
                                                           March 31,
                                                   -------------------------
                                                      2001           2000
                                                   ----------     ----------

                                                            
Revenues:
   Oil and gas                                      $ 507,768      $ 417,066
   Interest                                             3,352          2,468
                                                    ---------      ---------
                                                      511,120        419,534
                                                    ---------      ---------
Costs and expenses:
   Oil and gas production                             232,146        216,331
   General and administrative                          18,723         12,903
   Depletion                                           20,549         21,606
                                                    ---------      ---------
                                                      271,418        250,840
                                                    ---------      ---------
Net income                                          $ 239,702      $ 168,694
                                                    =========      =========

Allocation of net income:
   General partners                                 $  63,540      $  45,512
                                                    =========      =========
   Limited partners                                 $ 176,162      $ 123,182
                                                    =========      =========
Net income per limited partnership interest         $    9.03      $    6.32
                                                    =========      =========





         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

  The accompanying notes are an integral part of these financial statements.

                                        4

   329



                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)







                                      General        Limited
                                      partners       partners         Total
                                     ----------     ----------      ----------


                                                           
Balance at January 1, 2001            $200,131     $1,493,312      $1,693,443

   Distributions                       (79,839)      (234,888)       (314,727)

   Net income                           63,540        176,162         239,702
                                      --------     ----------      ----------

Balance at March 31, 2001             $183,832     $1,434,586      $1,618,418
                                      ========     ==========      ==========







         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

  The accompanying notes are an integral part of these financial statements.

                                        5

   330



                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                         Three months ended
                                                             March 31,
                                                      -------------------------
                                                         2001           2000
                                                      ----------     ----------

                                                               
Cash flows from operating activities:
   Net income                                           $239,702       $168,694
   Adjustments to reconcile net income to net cash
     provided by operating activities:
      Depletion                                           20,549         21,606
 Changes in assets and liabilities:
   Accounts receivable                                    14,625        (22,640)
   Accounts payable                                        4,929          4,239
                                                        --------       --------
        Net cash provided by operating activities        279,805        171,899
                                                        --------       --------
Cash flows used in investing activities:
   Additions to oil and gas properties                    (1,751)        (1,743)

Cash flows used in financing activities:
   Cash distributions to partners                       (314,727)      (188,420)
                                                        --------       --------
Net decrease in cash                                     (36,673)       (18,264)
Cash at beginning of period                              169,055        143,823
                                                        --------       --------
Cash at end of period                                   $132,382       $125,559
                                                        ========       ========





         The financial information included herein has been prepared by
 the managing general partner without audit by independent public accountants.

 The accompanying notes are an integral part of these financial statements.

                                        6

   331



                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 83-A, Ltd. (the "Partnership") is a limited partnership
organized in 1983 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 22% to $507,768 for the three
months ended March 31, 2001 as compared to $417,066 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 10,168
barrels of oil, 3,676 barrels of natural gas liquids ("NGLs") and 25,707 mcf of
gas were sold, or 18,129 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 10,838 barrels of oil, 5,586 barrels of NGLs and
22,988 mcf of gas were sold, or 20,255 BOEs.

                                        7

   332




The average price received per barrel of oil increased $.61, or 2%, from $27.44
for the three months ended March 31, 2000 to $28.05 for the same period in 2001.
The average price received per barrel of NGLs increased $4.89, or 34%, from
$14.18 for the three months ended March 31, 2000 to $19.07 for the same period
in 2001. The average price received per mcf of gas increased 237% from $1.76
during the three months ended March 31, 2000 to $5.93 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $271,418 for the three months ended March
31, 2001 as compared to $250,840 for the same period in 2000, an increase of
$20,578, or 8%. This increase was attributable to increases in production costs
and general and administrative expenses ("G&A"), offset by a decline in
depletion.

Production costs were $232,146 for the three months ended March 31, 2001 and
$216,331 for the same period in 2000 resulting in a $15,815 increase, or 7%. The
increase was primarily due to additional well maintenance costs incurred to
stimulate well production and higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 45% from $12,903 for the three months ended March 31, 2000 to $18,723
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $20,549 for the three months ended March 31, 2001 as compared to
$21,606 for the same period in 2000, a decrease of $1,057, or 5%. The decrease
was primarily due to a decrease in oil production of 670 barrels for the period
ended March 31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $107,906 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to an increase of $91,586 in oil and gas sales receipts and a reduction in
working capital of $37,955, offset by increases in production costs of $15,815
and G&A expenses of $5,820. The increase in oil and gas receipts resulted from
the increase in commodity prices during 2001 which contributed an additional
$130,676 to oil and gas receipts, offset by $39,090 resulting from the decline
in production during 2001 as compared to the same period in 2000. The increase
in production costs was primarily due to additional well maintenance costs
incurred to stimulate well production and increased production taxes associated

                                        8

   333



with higher oil and gas prices. The increase in G&A was primarily due to a
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues and
an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's investing activities during the three months ended March 31,
2001 and 2000 were related to expenditures for equipment upgrades on active oil
and gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $314,727, of which $79,839 was distributed to the general partners and
$234,888 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $188,420, of which $47,594 was distributed to
the general partners and $140,826 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

------------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.

                           Part II. Other Information

Item 6.       Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.


                                        9

   334


                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



      Pursuant to the requirements of the  Securities Exchange Act of 1934,  the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                                        PARKER & PARSLEY 83-A, LTD.

                              By:      Pioneer Natural Resources USA, Inc.
                                        Managing General Partner



Dated:  May 8, 2001           By:      /s/ Rich Dealy
                                       ----------------------------------
                                       Rich Dealy, Vice President
                                         and Chief Accounting Officer


                                       10



   335

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 2-81398A


                           PARKER & PARSLEY 83-A, LTD.
             (Exact name of Registrant as specified in its charter)


                                                                                 
                         TEXAS                                                            75-1891384
           -------------------------------                                          ---------------------
           (State or other jurisdiction of                                             (I.R.S. Employer
           incorporation or organization)                                           Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                         75039
----------------------------------------------------------------                      -----------
         (Address of principal executive offices)                                      (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


               Securities registered pursuant to Section 12(b) of
                 the Act: NONE Securities registered pursuant to
                            Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.  YES /X/   NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.      /X/

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$18,829,000.

        As of March 8, 2001, the number of outstanding limited partnership
interests was 19,505.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   336


                                     PART I

ITEM 1.         BUSINESS

Parker & Parsley 83-A, Ltd. (the "Partnership") is a limited partnership
organized in 1983 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA")
and its co-general partner is P&P Employees 83-A, Ltd. ("EMPL"), a Texas limited
partnership whose general partner is Pioneer USA. Pioneer USA is a wholly-owned
subsidiary of Pioneer Natural Resources Company ("Pioneer"). As of March 8,
2001, the Partnership had 19,505 limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 53% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations. The oil and gas business is
also subject to environmental hazards such as oil spills, gas leaks and ruptures
and discharges of toxic substances or gases that could expose the Partnership to
substantial liability due to pollution and other environmental damages. Although
the Partnership believes that



                                       2
   337


its business operations do not impair environmental quality and that its costs
of complying with any applicable environmental regulations are not currently
significant, the Partnership cannot predict what, if any, effect these
environmental regulations may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.         PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 69
oil and gas wells. Two wells were dry holes from previous periods, 22 wells have
been sold and three wells have been plugged and abandoned due to unprofitable
operations. At December 31, 2000, 42 wells were producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.         LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.         SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.




                                       3
   338


                                     PART II


ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                DISTRIBUTIONS

At March 8, 2001, the Partnership had 19,505 outstanding limited partnership
interests held of record by 1,273 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $659,311 and
$181,573, respectively, were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                         2000            1999            1998            1997            1996
                                     ------------    ------------    ------------    ------------    ------------
                                                                                      
Operating results:
------------------
 Oil and gas sales                   $  1,929,701    $  1,176,562    $    910,252    $  1,402,306    $  1,768,325
                                     ============    ============    ============    ============    ============

 Impairment of oil and gas
    properties                       $         --    $         --    $    430,351    $  1,194,023    $         --
                                     ============    ============    ============    ============    ============

 Gain on litigation
    settlement, net                  $         --    $         --    $         --    $         --    $    852,211
                                     ============    ============    ============    ============    ============

 Net income (loss)                   $    929,165    $    229,546    $   (784,583)   $   (811,642)   $  1,483,261
                                     ============    ============    ============    ============    ============

 Allocation of net income
    (loss):
      General partners               $    246,105    $     82,467    $    (52,520)   $     (1,662)   $    389,185
                                     ============    ============    ============    ============    ============

      Limited partners               $    683,060    $    147,079    $   (732,063)   $   (809,980)   $  1,094,076
                                     ============    ============    ============    ============    ============

 Limited partners' net
    income (loss) per limited
    partnership interest             $      35.02    $       7.54    $     (37.53)   $     (41.53)   $      56.09
                                     ============    ============    ============    ============    ============

 Limited partners' cash
    distributions per limited
    partnership interest             $      33.80    $       9.31    $      20.73    $      24.50    $       72.73(a)
                                     ============    ============    ============    ============    ============

At year end:
------------
 Identifiable assets                 $  1,727,226    $  1,684,906    $  1,691,709    $  3,015,116    $  4,459,272
                                     ============    ============    ============    ============    ============



---------------

(a)     Including litigation settlement per limited partnership interest of
        $34.33 in 1996.



                                       4
   339


ITEM 7.         MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                 RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 64% to $1,929,701 for 2000 as
compared to $1,176,562 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 43,334
barrels of oil, 23,345 barrels of natural gas liquids ("NGLs") and 94,612 mcf of
gas were sold, or 82,448 barrel of oil equivalents ("BOEs"). In 1999, 43,654
barrels of oil, 25,584 barrels of NGLs and 109,716 mcf of gas were sold, or
87,524 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.58, or 74%, from
$16.96 in 1999 to $29.54 in 2000. The average price received per barrel of NGLs
increased $6.16, or 65%, from $9.42 in 1999 to $15.58 in 2000. The average price
received per mcf of gas increased 70% from $1.78 in 1999 to $3.02 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $1,801 recognized during 1999 was related to
equipment credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $1,014,313 as compared to $955,718
in 1999, an increase of $58,595, or 6%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $867,551 in 2000 and $756,020 in 1999, resulting in a
$111,531 increase, or 15%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees, computer
services, postage and managing general partner personnel costs. During this
period, G&A increased 39% from $47,303 in 1999 to $65,724 in 2000 primarily due
to a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues. The Partnership paid the managing general partner $57,891 in 2000 and
$35,297 in 1999 for G&A incurred on behalf of the Partnership. The remaining G&A
was paid directly by the Partnership. The managing general partner determines
the allocated expenses based upon the level of activity of the Partnership
relative to the non-partnership activities of the managing general partner. The
method of allocation has been consistent over the past several years with
certain modifications incorporated to reflect changes in Pioneer USA's overall
business activities.



                                       5
   340


Depletion was $81,038 in 2000 as compared to $152,395 in 1999. This represented
a decrease of $71,357, or 47%. The decrease was primarily due to a 129,265
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 29% to $1,176,562 from
$910,252 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production from 1998 to 1999. In 1999, 43,654
barrels of oil, 25,584 barrels of NGLs and 109,716 mcf of gas were sold, or
87,524 BOEs. In 1998, 46,586 barrels of oil, 21,026 barrels of NGLs and 95,156
mcf of gas were sold, or 83,471 BOEs.

The average price received per barrel of oil increased $3.62, or 27%, from
$13.34 in 1998 to $16.96 in 1999. The average price received per barrel of NGLs
increased $2.93, or 45%, from $6.49 in 1998 to $9.42 in 1999. The average price
received per mcf of gas increased 11% from $1.60 in 1998 to $1.78 in 1999.

A gain on disposition of assets of $1,801 recognized during 1999 was related to
equipment credits received on one fully depleted well while the $3,702 gain
recognized during 1998 was from final closing adjustments from the sale during
1997 of 16 oil and gas wells.

Total costs and expenses decreased in 1999 to $955,718 as compared to $1,715,723
in 1998, a decrease of $760,005, or 44%. The decrease was primarily due to
declines in the impairment of oil and gas properties and depletion, offset by
increases in production costs and G&A expenses.

Production costs were $756,020 in 1999 and $731,005 in 1998, resulting in a
$25,015 increase, or 3%. The increase was attributable to additional well
maintenance costs incurred to stimulate well production and production taxes due
to increased oil and gas revenues, offset by a decline in ad valorem taxes.

During this period, G&A increased 43% from $33,000 in 1998 to $47,303 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $35,297 in
1999 and $27,308 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $430,351 related to its oil and gas properties during 1998.

Depletion was $152,395 in 1999 compared to $521,367 in 1998. This represented a
decrease of $368,972, or 71%. The decrease was the result of an increase in
proved reserves of 416,430 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.



                                       6
   341


Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $620,642 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $760,015, offset by increases in production costs paid
of $111,531, G&A expenses paid of $18,421 and working capital of $9,421. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $849,987 to oil and gas receipts,
offset by $89,973 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production. The increase in G&A was
primarily due to higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on various oil and gas properties.

Proceeds from asset dispositions in 1999 of $2,611 were from equipment credits
received on active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $887,776, of which $228,465 was
distributed to the general partners and $659,311 to the limited partners. In
1999, cash distributions to the partners were $245,794, of which $64,221 was
distributed to the general partners and $181,573 to the limited partners.



                                       7
   342


ITEM 8.         FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


                          INDEX TO FINANCIAL STATEMENTS



                                                                                                    Page
                                                                                                    ----
                                                                                                 
Financial Statements of Parker & Parsley 83-A, Ltd:
  Independent Auditors' Report................................................................        9
  Balance Sheets as of December 31, 2000 and 1999.............................................       10
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998.......................................................................       11
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998..........................................................       12
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998.......................................................................       13
  Notes to Financial Statements...............................................................       14




                                       8
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                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 83-A, Ltd.
 (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 83-A, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 83-A, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                             Ernst & Young LLP

Dallas, Texas
March 9, 2001



                                       9
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                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                           2000              1999
                                                       ------------      ------------
                                                                   
                ASSETS
                ------

Current assets:
   Cash                                                $    169,055      $    143,823
   Accounts receivable - oil and gas sales                  279,239           189,995
                                                       ------------      ------------

          Total current assets                              448,294           333,818
                                                       ------------      ------------

Oil and gas properties - at cost, based on the
   successful efforts accounting method                  16,901,194        16,892,307
Accumulated depletion                                   (15,622,262)      (15,541,219)
                                                       ------------      ------------

          Net oil and gas properties                      1,278,932         1,351,088
                                                       ------------      ------------

                                                       $  1,727,226      $  1,684,906
                                                       ============      ============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
   Accounts payable - affiliate                        $     33,783      $     32,852

Partners' capital:
   General partners                                         200,131           182,491
   Limited partners (19,505 interests)                    1,493,312         1,469,563
                                                       ------------      ------------

                                                          1,693,443         1,652,054
                                                       ------------      ------------

                                                       $  1,727,226      $  1,684,906
                                                       ============      ============







   The accompanying notes are an integral part of these financial statements.



                                       10
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                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                               2000             1999            1998
                                                            -----------     -----------     -----------
                                                                                   

Revenues:
  Oil and gas                                               $ 1,929,701     $ 1,176,562     $   910,252
  Interest                                                       13,777           6,901          17,186
  Gain on disposition of assets                                       -           1,801           3,702
                                                            -----------     -----------     -----------

                                                              1,943,478       1,185,264         931,140
                                                            -----------     -----------     -----------

Costs and expenses:
  Oil and gas production                                        867,551         756,020         731,005
  General and administrative                                     65,724          47,303          33,000
  Impairment of oil and gas properties                                -               -         430,351
  Depletion                                                      81,038         152,395         521,367
                                                            -----------     -----------     -----------

                                                              1,014,313         955,718       1,715,723
                                                            -----------     -----------     -----------

Net income (loss)                                           $   929,165     $   229,546     $  (784,583)
                                                            ===========     ===========     ===========

Allocation of net income (loss):
  General partners                                          $   246,105     $    82,467     $   (52,520)
                                                            ===========     ===========     ===========

  Limited partners                                          $   683,060     $   147,079     $  (732,063)
                                                            ===========     ===========     ===========

Net income (loss) per limited partnership interest          $     35.02     $      7.54     $    (37.53)
                                                            ===========     ===========     ===========






   The accompanying notes are an integral part of these financial statements.



                                       11
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                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                   General          Limited
                                                   partners         partners          Total
                                                 -----------      -----------      -----------
                                                                          

Partners' capital at January 1, 1998             $   336,024      $ 2,640,444      $ 2,976,468

    Distributions                                   (119,259)        (404,324)        (523,583)

    Net loss                                         (52,520)        (732,063)        (784,583)
                                                 -----------      -----------      -----------

Partners' capital at December 31, 1998               164,245        1,504,057        1,668,302

    Distributions                                    (64,221)        (181,573)        (245,794)

    Net income                                        82,467          147,079          229,546
                                                 -----------      -----------      -----------

Partners' capital at December 31, 1999               182,491        1,469,563        1,652,054

    Distributions                                   (228,465)        (659,311)        (887,776)

    Net income                                       246,105          683,060          929,165
                                                 -----------      -----------      -----------

Partners' capital at December 31, 2000           $   200,131      $ 1,493,312      $ 1,693,443
                                                 ===========      ===========      ===========






   The accompanying notes are an integral part of these financial statements.



                                       12
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                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                               2000           1999           1998
                                                            ---------      ---------      ---------
                                                                                 

Cash flows from operating activities:
   Net income (loss)                                        $ 929,165      $ 229,546      $(784,583)
   Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
       Impairment of oil and gas properties                         -              -        430,351
       Depletion                                               81,038        152,395        521,367
       Gain on disposition of assets                                -         (1,801)        (3,702)
   Changes in assets and liabilities:
       Accounts receivable                                    (89,244)       (88,337)        39,919
       Accounts payable                                           931          9,445        (15,241)
                                                            ---------      ---------      ---------

          Net cash provided by operating activities           921,890        301,248        188,111
                                                            ---------      ---------      ---------

Cash flows from investing activities:
   Additions to oil and gas properties                         (8,882)        (8,942)       (14,943)
   Proceeds from asset dispositions                                 -          2,611        271,839
                                                            ---------      ---------      ---------

          Net cash provided by (used in) investing
           activities                                          (8,882)        (6,331)       256,896
                                                            ---------      ---------      ---------

Cash flows used in financing activities:
   Cash distributions to partners                            (887,776)      (245,794)      (523,583)
                                                            ---------      ---------      ---------

Net increase (decrease) in cash                                25,232         49,123        (78,576)
Cash at beginning of year                                     143,823         94,700        173,276
                                                            ---------      ---------      ---------

Cash at end of year                                         $ 169,055      $ 143,823      $  94,700
                                                            =========      =========      =========






   The accompanying notes are an integral part of these financial statements.



                                       13
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                           PARKER & PARSLEY 83-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 83-A, Ltd. (the "Partnership") is a limited partnership
organized in 1983 under the laws of the State of Texas. The Partnership's
general partners are Pioneer Natural Resources USA, Inc. ("Pioneer USA") and P&P
Employees 83-A, Ltd. ("EMPL"). The Partnership's managing general partner is
Pioneer USA.

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.



                                       14
   349


        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of



                                       15
   350


$430,351 related to its proved oil and gas properties during 1998.

NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $1,081,971 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                               2000           1999           1998
                                                            ---------      ---------      ---------
                                                                                 

Net income (loss) per statements of operations              $ 929,165      $ 229,546      $(784,583)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                                 72,648        144,177        510,610
Impairment of oil and gas properties for financial
  reporting purposes                                                -              -        430,351
Other, net                                                     (2,243)          (235)           891
                                                            ---------      ---------      ---------

        Net income per Federal income tax
         returns                                            $ 999,570      $ 373,488      $ 157,269
                                                            =========      =========      =========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                  2000        1999        1998
                                -------     -------     -------
                                               

Development costs               $ 8,882     $ 8,942     $14,943
                                =======     =======     =======



        Capitalized oil and gas properties consist of the following:



                                                      2000              1999
                                                  ------------      ------------
                                                              

Proved properties:
  Property acquisition costs                      $  1,000,072      $  1,000,072
  Completed wells and equipment                     15,901,122        15,892,235
                                                  ------------      ------------

                                                    16,901,194        16,892,307
  Accumulated depletion                            (15,622,262)      (15,541,219)
                                                  ------------      ------------

              Net oil and gas properties          $  1,278,932      $  1,351,088
                                                  ============      ============




                                       16
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NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999          1998
                                                   ---------     ---------     ---------
                                                                      

Payment of lease operating and supervision
   charges in accordance with standard
   industry operating agreements                   $ 407,783     $ 397,884     $ 370,984

Reimbursement of general and administrative
   expenses                                        $  57,891     $  35,297     $  27,308



        Pioneer USA, EMPL and the Partnership are parties to the partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 79% and the
remaining portion is owned by former affiliates. In addition, Pioneer USA owned
676 limited partner interests at January 1, 2001.

        The costs and revenues of the Partnership are allocated as follows:



                                                                  General    Limited
                                                                  partners   partners
                                                                  --------   --------
                                                                       

Revenues:
  Proceeds from property dispositions prior to cost
    recovery                                                        10%        90%
All other Partnership revenues                                      25%        75%
Costs and expenses:
  Lease acquisition costs, drilling and completion costs            10%        90%
  Operating costs, direct costs and general and
    administrative expenses                                         25%        75%
Incremental direct expenses                                          -        100%



        Incremental direct expenses are direct expenses which would not be
incurred except for the requirements of the securities regulatory authorities.
Such expenses totaled $7,833, $12,006 and $5,692 in 2000, 1999 and 1998,
respectively.

NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                                    Oil and NGLs          Gas
                                                       (bbls)            (mcf)
                                                    ------------      ----------
                                                                

Net proved reserves at January 1, 1998                 765,491         1,179,867
Revisions                                             (361,806)         (528,746)
Production                                             (67,612)          (95,156)
                                                    ----------        ----------

Net proved reserves at December 31, 1998               336,073           555,965
Revisions                                              714,690         1,245,944
Production                                             (69,238)         (109,716)
                                                    ----------        ----------

Net proved reserves at December 31, 1999               981,525         1,692,193
Revisions                                              124,418           (56,128)
Production                                             (66,679)          (94,612)
                                                    ----------        ----------

Net proved reserves at December 31, 2000             1,039,264         1,541,453
                                                    ==========        ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.61
per barrel



                                       17
   352


of oil, $13.13 per barrel of NGLs and $7.87 per mcf of gas, discounted at 10%
was approximately $7,532,000 and undiscounted was $14,892,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                        For the years ended December 31,
                                                                  -------------------------------------------
                                                                     2000            1999              1998
                                                                  ---------        ---------        ---------
                                                                                (in thousands)
                                                                                           

Oil and gas producing activities:
   Future cash inflows                                            $  34,721        $  24,100        $   3,651
   Future production costs                                          (19,829)         (14,511)          (2,932)
                                                                  ---------        ---------        ---------

                                                                     14,892            9,589              719
   10% annual discount factor                                        (7,360)          (4,422)            (207)
                                                                  ---------        ---------        ---------

   Standardized measure of discounted future net cash flows       $   7,532        $   5,167        $     512
                                                                  =========        =========        =========





                                       18
   353




                                                                   For the years ended December 31,
                                                              -----------------------------------------
                                                                2000            1999            1998
                                                              --------        --------        --------
                                                                           (in thousands)
                                                                                     

Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs                  $ (1,062)       $   (421)       $   (179)
  Net changes in prices and production costs                     2,717           1,751          (1,843)
  Revisions of previous quantity estimates                         713           4,985            (450)
  Accretion of discount                                            517              51             285
  Changes in production rates, timing and other                   (520)         (1,711)           (151)
                                                              --------        --------        --------

  Change in present value of future net revenues                 2,365           4,655          (2,338)
                                                              --------        --------        --------

  Balance, beginning of year                                     5,167             512           2,850
                                                              --------        --------        --------

  Balance, end of year                                        $  7,532        $  5,167        $    512
                                                              ========        ========        ========



NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                         2000      1999       1998
                                        ------    ------     ------
                                                    

Plains Marketing, L.P.                    53%       52%        -
Genesis Crude Oil, L.P.                    -         -        64%
Western Gas Resources, Inc.                3%        5%       17%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $100,032 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        General partners - The general partners of the Partnership are Pioneer
        USA and EMPL. Pioneer USA, the managing general partner, has the power
        and authority to manage, control and administer all Partnership affairs.
        As managing general partner and operator of the Partnership's
        properties, all production expenses are incurred by Pioneer USA and
        billed to the Partnership. The majority of the Partnership's oil and gas
        revenues are received directly by the Partnership, however, a portion of
        the oil and gas revenue is initially received by Pioneer USA prior to
        being paid to the Partnership.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $19,505,000. The general partners are required to contribute amounts
        equal to 10% of Partnership expenditures for lease acquisition, drilling
        and



                                       19
   354


        completion and 25% of direct, general and administrative and operating
        expenses.

ITEM 9.         CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
                 FINANCIAL DISCLOSURE

None.




                                       20
   355


                                    PART III

ITEM 10.        DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                               Age at
                                            December 31,
        Name                                    2000                        Position
        ----                                    ----                        --------
                                                              
Scott D. Sheffield                               48                 President

Timothy L. Dove                                  44                 Executive Vice President, Chief
                                                                      Financial Officer and Director

Dennis E. Fagerstone                             51                 Executive Vice President and Director

Mark L. Withrow                                  53                 Executive Vice President, General
                                                                      Counsel and Director

Danny Kellum                                     46                 Executive Vice President - Domestic
                                                                    Operations and Director

Rich Dealy                                       34                 Vice President and Chief Accounting
                                                                      Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts



                                       21
   356


Institute of Technology in 1979 and received his M.B.A. in 1981 from the
University of Chicago. He became Executive Vice President - Business Development
of Pioneer and Pioneer USA in August 1997 and was also appointed a director of
Pioneer USA in August 1997. Mr. Dove assumed the position of Chief Financial
Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr. Dove joined
Parker & Parsley in May 1994 as Vice President - International and was promoted
to Senior Vice President - Business Development in October 1996, in which
position he served until August 1997. Prior to joining Parker & Parsley, Mr.
Dove was employed with Diamond Shamrock Corp., and its successor, Maxus Energy
Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   357


ITEM 11.        EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. Under the
partnership agreement, Pioneer USA pays 8% of the Partnership's acquisition,
drilling and completion costs and 20% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 20% of the
Partnership's revenues.

EMPL is a co-general partner of the Partnership. Under this arrangement, EMPL
pays 2% of the Partnership's acquisition, drilling and completion costs and 5%
of its operating and general and administrative expenses. In return, EMPL is
allocated 5% of the Partnership's revenues. EMPL does not receive any fees or
reimbursements from the Partnership.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.        SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)     Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
and EMPL respectively own 80% and 20% of the general partners' interests in the
Partnership. Pioneer USA owned 676 limited partner interests at January 1, 2001.

(b)     Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.



                                       23
   358


ITEM 13.        CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                         2000           1999           1998
                                                       --------       --------       --------
                                                                            

Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                        $407,783       $397,884       $370,984

Reimbursement of general and administrative
  expenses                                             $ 57,891       $ 35,297       $ 27,308


Under the limited partnership agreement, the general partners, Pioneer USA and
EMPL, together pay 10% of the Partnership's acquisition, drilling and completion
costs and 25% of its operating and general and administrative expenses. In
return, they are allocated 25% of the Partnership's revenues. Twenty percent of
the general partners' share of costs and revenues is allocated to EMPL and the
remainder is allocated to Pioneer USA. Certain former affiliates of Pioneer USA
are limited partners of EMPL. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Partnership.



                                       24
   359


                                     PART IV

ITEM 14.        EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                  1999 and 1998

                Statements of partners' capital for the years ended December 31,
                  2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                  1999 and 1998

                Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   360


                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                 PARKER & PARSLEY 83-A, LTD.

Dated: March 23, 2001            By:   Pioneer Natural Resources USA, Inc.
                                         Managing General Partner


                                       By:   /s/ Scott D. Sheffield
                                             ----------------------------------
                                             Scott D. Sheffield, President


        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                                         
/s/ Scott D. Sheffield                      President of Pioneer USA                           March 23, 2001
--------------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                         Executive Vice President, Chief                    March 23, 2001
--------------------------------------      Financial Officer and Director of
Timothy L. Dove                             Pioneer USA


/s/ Dennis E. Fagerstone                    Executive Vice President and                       March 23, 2001
--------------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                         Executive Vice President, General                  March 23, 2001
--------------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                            Executive Vice President - Domestic                March 23, 2001
--------------------------------------      Operations and Director of Pioneer
Danny Kellum                                USA


/s/ Rich Dealy                              Vice President and Chief Accounting                March 23, 2001
--------------------------------------      Officer of Pioneer USA
Rich Dealy




                                       26
   361


                           PARKER & PARSLEY 83-A, LTD.

                                INDEX TO EXHIBITS

        The following documents are incorporated by reference in response to
Item 14(c):



Exhibit No.                      Description                                       Page
-----------                      -----------                                       ----
                                                                             
    3.1             Agreement of Limited Partnership of                              -
                    Parker & Parsley 83-A, Ltd. incorporated
                    by reference to Exhibit 4(e) of Partnership's
                    Registration Statement on Form S-1
                    (Registration No. 2-81398A), as amended
                    on April 26, 1983, the effective date thereof
                    (hereinafter called, the Partnership's
                    Registration Statement)

    3.2             Amended and Restated Certificate of                              -
                    Limited Partnership of Parker & Parsley 83-A,
                    Ltd. incorporated by reference to Exhibit 3.2
                    of the Partnership's Annual Report on Form
                    10-K for the period from July 1, 1983 (date
                    of organization) through December 31, 1983

    4.1             Form of Subscription Agreement and                               -
                    Power of Attorney incorporated by reference
                    to Exhibit 4(b) of the Partnership's Registration
                    Statement

    4.2             Specimen Certificate of Limited Partnership                      -
                    Interest incorporated by reference to Exhibit
                    4(d) of the Partnership's Registration Statement





                                       27

   362


                           PARKER & PARSLEY 83-A, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                           ended
                                          March 31,                           Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  417,066   $1,929,701   $1,176,562   $  910,252   $1,402,306   $1,768,325
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
    properties                     $          $       --   $       --   $       --   $  430,351   $1,194,023   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $     --   $       --   $       --   $       --   $       --   $       --   $  852,211
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  168,694   $  929,165   $  229,546   $ (784,583)  $ (811,642)  $1,483,261
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
         General partners          $          $   45,512   $  246,105   $   82,467   $  (52,520)  $   (1,662)  $  389,185
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  123,182   $  683,060   $  147,079   $ (732,063)  $ (809,980)  $1,094,076
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     6.32   $    35.02   $     7.54   $   (37.53)  $   (41.53)  $    56.09
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $     7.22   $    33.80   $     9.31   $    20.73   $    24.50   $    72.73(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,669,419   $1,727,226   $1,684,906   $1,691,709   $3,015,116   $4,459,272
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)   Including litigation settlement per limited partnership interest of $34.33
      in 1996.

   363
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 83-B, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
83-B, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 83-B, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-
   364
                           PARKER & PARSLEY 83-B, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $  23,370

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $  35,807

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   3,473
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  154.41

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.60 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $   79.98

          --  as of December 31, 2000 (c)                                                     $   83.30

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  142.64

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  149.96

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     225
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.

                                      -2-

   365

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 2-81398B


                           PARKER & PARSLEY 83-B, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                               75-1907245
          ---------------------------------           ---------------------
           (State or other jurisdiction of               (I.R.S. Employer
           incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [X]   No [ ]



   366

                          PARKER & PARSLEY 83-B, LTD.

                                TABLE OF CONTENTS





                                                                        Page
                                                                     
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000......................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000...........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001....................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000...........................    6

            Notes to Financial Statements.............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K..........................   10

            Signatures................................................   11




                                        2

   367


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements


                                 BALANCE SHEETS




                                                            March 31,          December 31,
                                                              2001                 2000
                                                          ------------         ------------
                                                           (Unaudited)
                                                                         

                      ASSETS

Current assets:
   Cash                                                   $    199,783         $    224,865
   Accounts receivable - oil and gas sales                     316,380              369,349
                                                          ------------         ------------
            Total current assets                               516,163              594,214
                                                          ------------         ------------
Oil and gas properties - at cost, based on the
   successful efforts accounting method                     18,961,997           18,957,070
Accumulated depletion                                      (17,272,688)         (17,248,214)
                                                          ------------         ------------
            Net oil and gas properties                       1,689,309            1,708,856
                                                          ------------         ------------
                                                          $  2,205,472         $  2,303,070
                                                          ============         ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable - affiliate                           $     43,415         $     39,862

Partners' capital:
   General partners                                            292,844              316,574
   Limited partners (23,370 interests)                       1,869,213            1,946,634
                                                          ------------         ------------
                                                             2,162,057            2,263,208
                                                          ------------         ------------
                                                          $  2,205,472         $  2,303,070
                                                          ============         ============


The financial information included as of March 31, 2001 has been prepared by
the managing general partner without audit by independent public accountants.


   The accompanying notes are an integral part of these financial statements.


                                        3


   368


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                                  Three months ended
                                                                      March 31,
                                                          --------------------------------
                                                              2001                2000
                                                          ------------        ------------
                                                                        
Revenues:
   Oil and gas                                            $    567,450        $    550,469
   Interest                                                      4,255               3,909
   Gain on disposition of assets                                    --               3,923
                                                          ------------        ------------
                                                               571,705             558,301
                                                          ------------        ------------
Costs and expenses:
   Oil and gas production                                      278,432             232,950
   General and administrative                                   20,536              16,889
   Depletion                                                    24,474              29,860
                                                          ------------        ------------
                                                               323,442             279,699
                                                          ------------        ------------
Net income                                                $    248,263        $    278,602
                                                          ============        ============
Allocation of net income:
   General partners                                       $     66,275        $     73,635
                                                          ============        ============
   Limited partners                                       $    181,988        $    204,967
                                                          ============        ============
Net income per limited partnership interest               $       7.79        $       8.77
                                                          ============        ============


         The financial information included herein has been prepared by
 the managing general partner without audit by independent public accountants.

 The accompanying notes are an integral part of these financial statements.


                                        4

   369


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                        General             Limited
                                        partners           partners              Total
                                      -----------         -----------         -----------
                                                                     
Balance at January 1, 2001            $   316,574         $ 1,946,634         $ 2,263,208

   Distributions                          (90,005)           (259,409)           (349,414)

   Net income                              66,275             181,988             248,263
                                      -----------         -----------         -----------

Balance at March 31, 2001             $   292,844         $ 1,869,213         $ 2,162,057
                                      ===========         ===========         ===========



         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        5

   370


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                                 Three months ended
                                                                      March 31,
                                                          ---------------------------------
                                                              2001                 2000
                                                          ------------         ------------

                                                                         
Cash flows from operating activities:
  Net income                                              $    248,263         $    278,602
  Adjustments to reconcile net income to
      net cash provided by operating activities:
        Depletion                                               24,474               29,860
        Gain on disposition of assets                               --               (3,923)
Changes in assets and liabilities:
  Accounts receivable                                           52,969              (33,759)
  Accounts payable                                               3,553                7,667
                                                          ------------         ------------
         Net cash provided by operating activities             329,259              278,447
                                                          ------------         ------------
Cash flows from investing activities:
  Additions to oil and gas properties                           (4,927)                (303)
  Proceeds from disposition of assets                               --                3,923
                                                          ------------         ------------
         Net cash provided by (used in) investing
           activities                                           (4,927)               3,620
                                                          ------------         ------------
Cash flows used in financing activities:
  Cash distributions to partners                              (349,414)            (272,131)
                                                          ------------         ------------
Net increase (decrease) in cash                                (25,082)               9,936
Cash at beginning of period                                    224,865              244,091
                                                          ------------         ------------
Cash at end of period                                     $    199,783         $    254,027
                                                          ============         ============



         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        6

   371


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of organization

Parker &  Parsley  83-B,  Ltd.  (the  "Partnership")  is a  limited  partnership
organized in 1983 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.      Management's Discussion and Analysis of Financial Condition and
                Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 3% to $567,450 for the three
months ended March 31, 2001 as compared to $550,469 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 10,605
barrels of oil, 5,172 barrels of natural gas liquids ("NGLs") and 29,602 mcf of
gas were sold, or 20,711 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 13,733 barrels of oil, 8,049 barrels of NGLs and
35,379 mcf of gas were sold, or 27,679 BOEs.


                                        7

   372


The average price received per barrel of oil increased $.73, or 3%, from $27.66
for the three months ended March 31, 2000 to $28.39 for the same period in 2001.
The average price received per barrel of NGLs increased $5.18, or 38%, from
$13.48 for the three months ended March 31, 2000 to $18.66 for the same period
in 2001. The average price received per mcf of gas increased 226% from $1.76
during the three months ended March 31, 2000 to $5.74 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

A gain on disposition of assets of $3,923 during 2000 was recognized from
equipment credits received on one fully depleted well.

Costs and Expenses:

Total costs and expenses increased to $323,442 for the three months ended March
31, 2001 as compared to $279,699 for the same period in 2000, an increase of
$43,743, or 16%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $278,432 for the three months ended March 31, 2001 and
$232,950 for the same period in 2000 resulting in a $45,482 increase, or 20%.
The increase was primarily due to additional workover and well maintenance costs
incurred to stimulate well production and higher production taxes associated
with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 22% from $16,889 for the three months ended March 31, 2000 to $20,536
for the same period in 2001 primarily, due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $24,474 for the three months ended March 31, 2001 as compared to
$29,860 for the same period in 2000, a decrease of $5,386, or 18%. This decrease
was primarily due to a reduction in the Partnership's net depletable basis from
charges taken in accordance with Statement of Financial Accounting Standards No.
121, "Accounting for the Impairment of Long-Lived Assets and for Long-Lived
Assets to be Disposed Of" ("SFAS 121") during the fourth quarter of 2000 and a
decline in oil production of 3,128 barrels for the three months ended March 31,
2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities:

Net cash provided by operating activities increased $50,812 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due


                                        8

   373



to an increase of $17,327 in oil and gas sales receipts and a reduction in
working capital of $82,614, offset by increases in production costs of $45,482
and G&A expenses of $3,647. The increase in oil and gas receipts resulted from
the increase in commodity prices during 2001 which contributed an additional
$192,976 to oil and gas receipts, offset by $175,649 resulting from the decline
in production during 2001 as compared to the same period in 2000. The increase
in production costs was primarily due to additional workover and well
maintenance costs incurred to stimulate well production and increased production
taxes associated with higher oil and gas prices. The increase in G&A was
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues and an increase in the accrual for tax preparation fees.

Cash Provided by (Used in) Investing Activities:

The Partnership's investing activities for the three months ended March 31, 2001
and 2000 were for expenditures related to oil and gas equipment upgrades on
active properties.

Proceeds from disposition of assets of $3,923 recognized during the three months
ended March 31, 2000 were from equipment credits received on one fully depleted
well.

Net Cash Used in Financing Activities:

For the three months ended March 31, 2001, cash distributions to the partners
were $349,414, of which $90,005 was distributed to the general partners and
$259,409 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $272,131, of which $68,700 was distributed to
the general partners and $203,431 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)     "Item 2. Management's Discussion and Analysis of Financial Condition and
        Results of Operations" contains forward looking statements that involve
        risks and uncertainties. Accordingly, no assurances can be given that
        the actual events and results will not be materially different than the
        anticipated results described in the forward looking statements.


                                        9

   374


                           Part II. Other Information


Item 6.      Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.




                                       10

   375


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)


                                   SIGNATURES



      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                  PARKER & PARSLEY 83-B, LTD.

                              By:      Pioneer Natural Resources USA, Inc.
                                        Managing General Partner



Dated:  May 8, 2001           By:      /s/ Rich Dealy
                                       -------------------------------------
                                       Rich Dealy, Vice President
                                         and Chief Accounting Officer


                                       11

   376

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 2-81398B


                           PARKER & PARSLEY 83-B, LTD.
             (Exact name of Registrant as specified in its charter)


                                                                                
                          TEXAS                                                          75-1907245
             ---------------------------------                                     ----------------------
              (State or other jurisdiction of                                         (I.R.S. Employer
              incorporation or organization)                                       Identification Number)

1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                         75039
----------------------------------------------------------------                     -----------
            (Address of principal executive offices)                                  (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


               Securities registered pursuant to Section 12(b) of
                 the Act: NONE Securities registered pursuant to
                            Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.   YES /X/   NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K.     /X/

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$22,493,000.

        As of March 8, 2001, the number of outstanding limited partnership
interests was 23,370.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None


PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.



   377


                                     PART I

ITEM 1.         BUSINESS

Parker & Parsley 83-B, Ltd. (the "Partnership") is a limited partnership
organized in 1983 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA")
and its co-general partner is P&P Employees 83-B, Ltd. ("EMPL"), a Texas limited
partnership whose general partner is Pioneer USA. Pioneer USA is a wholly-owned
subsidiary of Pioneer Natural Resources Company ("Pioneer"). As of March 8,
2001, the Partnership had 23,370 limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 46%, 13% and 10% were attributable to
sales made to Plains Marketing, L.P., TEPPCO Crude Oil LLC and Phillips
Petroleum Company, respectively. Pioneer USA is of the opinion that the loss of
any one purchaser would not have an adverse effect on its ability to sell its
oil, natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations. The oil and gas business is
also subject to environmental hazards such as oil spills, gas leaks and ruptures
and discharges of toxic substances or gases that could expose the Partnership to
substantial liability due to pollution and other environmental damages. Although
the Partnership believes that



                                       2
   378


its business operations do not impair environmental quality and that its costs
of complying with any applicable environmental regulations are not currently
significant, the Partnership cannot predict what, if any, effect these
environmental regulations may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.         PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in Texas were acquired by the Partnership, resulting in the
Partnership's participation in the drilling of 59 productive oil and gas wells.
At December 31, 2000, the Partnership had 41 producing wells. Thirteen wells
have been plugged and abandoned due to unprofitable operations and five wells
were sold.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.         LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.         SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                       3
   379


                                     PART II


ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                DISTRIBUTIONS

At March 8, 2001, the Partnership had 23,370 outstanding limited partnership
interests held of record by 1,379 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $942,688 and
$325,903, respectively, were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                      2000            1999            1998            1997            1996
                                  ------------    ------------    ------------    ------------    ------------
                                                                                   

Operating results:
------------------
 Oil and gas sales                $  2,376,791    $  1,548,013    $  1,267,241    $  1,924,748    $  2,291,605
                                  ============    ============    ============    ============    ============

 Gain on litigation
    settlement, net               $          -    $          -    $          -    $          -    $  1,392,304
                                  ============    ============    ============    ============    ============

 Impairment of oil and
    gas properties                $     84,697    $    152,505    $    362,325    $  1,171,409    $          -
                                  ============    ============    ============    ============    ============

 Net income (loss)                $  1,174,971    $    292,874    $   (871,809)   $   (754,107)   $  2,309,638
                                  ============    ============    ============    ============    ============

 Allocation of net
    income (loss):
       General partners           $    325,015    $    125,187    $    (46,980)   $     56,351    $    578,911
                                  ============    ============    ============    ============    ============

       Limited partners           $    849,956    $    167,687    $   (824,829)   $   (810,458)   $  1,730,727
                                  ============    ============    ============    ============    ============

 Limited partners' net
    income (loss) per
    limited partnership
    interest                      $      36.37    $       7.18    $     (35.29)   $     (34.68)   $      74.06
                                  ============    ============    ============    ============    ============

 Limited partners' cash
    distributions per
    limited partnership
    interest                      $      40.34    $      13.95    $      11.49    $      32.48    $      80.43(a)
                                  ============    ============    ============    ============    ============

At year end:
------------
 Identifiable assets              $  2,303,070    $  2,391,541    $  2,529,136    $  3,774,504    $  5,537,639
                                  ============    ============    ============    ============    ============



---------------

(a)     Including litigation settlement per limited partnership interest of
        $46.83 in 1996.



                                       4
   380



ITEM 7.         MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                 RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 54% to $2,376,791 for 2000 as
compared to $1,548,013 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 51,895
barrels of oil, 29,919 barrels of natural gas liquids ("NGLs") and 132,106 mcf
of gas were sold, or 103,832 barrel of oil equivalents ("BOEs"). In 1999, 54,446
barrels of oil, 35,000 barrels of NGLs and 157,842 mcf of gas were sold, or
115,753 BOEs. Due to the decline characteristics of the Partnership's oil and
gas properties, management expects a certain amount of decline in production in
the future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.51, or 73%, from
$17.18 in 1999 to $29.69 in 2000. The average price received per barrel of NGLs
increased $5.47, or 55%, from $10.00 in 1999 to $15.47 in 2000. The average
price received per mcf of gas increased 70% from $1.66 in 1999 to $2.83 in 2000.
The market price for oil and gas has been extremely volatile in the past decade
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

A gain on disposition of assets of $7,482 during 2000 was due to salvage income
received on one well plugged and abandoned during the current year. A gain of
$3,375 during 1999 was recognized from equipment credits received on one fully
depleted well.

Total costs and expenses decreased in 2000 to $1,230,645 as compared to
$1,270,634 in 1999, a decrease of $39,989, or 3%. The decrease was primarily due
to declines in depletion and the impairment of oil and gas properties, offset by
increases in production costs and general and administrative expenses ("G&A").

Production costs were $947,439 in 2000 and $879,335 in 1999, resulting in a
$68,104 increase, or 8%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees, and managing
general partner personnel and operating costs. During this period, G&A increased
35% from $58,993 in 1999 to $79,646 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $71,304 in 2000 and $46,440 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized
non-cash charges of $84,697 and $152,505 related to its oil and gas properties
during 2000 and 1999, respectively.



                                       5
   381


Depletion was $106,841 in 2000 as compared to $179,801 in 1999, representing a
decrease of $72,960, or 41%. This decrease was primarily due to a 115,324
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1999.

Abandoned property costs of $12,022 during 2000 was related to the plugging and
abandonment of one well during the current year.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 22% to $1,548,013 from
$1,267,241 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 54,446 barrels of oil,
35,000 barrels of NGLs and 157,842 mcf of gas were sold, or 115,753 BOEs. In
1998, 62,162 barrels of oil, 31,533 barrels of NGLs and 147,495 mcf of gas were
sold, or 118,278 BOEs.

The average price received per barrel of oil increased $3.88, or 29%, from
$13.30 in 1998 to $17.18 in 1999. The average price received per barrel of NGLs
increased $3.21, or 47%, from $6.79 in 1998 to $10.00 in 1999. The average price
received per mcf of gas increased 8% from $1.54 in 1998 to $1.66 in 1999.

A gain on disposition of assets of $3,375 during 1999 was recognized from
equipment credits received on one fully depleted well. During 1998, a gain on
disposition of assets of $157 was recognized from post closing adjustments
received from the sale of two oil and gas wells and an overriding royalty
interest on one well during 1997.

Total costs and expenses decreased in 1999 to $1,270,634 as compared to
$2,152,425 in 1998, a decrease of $881,791, or 41%. The decrease was primarily
due to declines in depletion, the impairment of oil and gas properties and
production costs, offset by an increase in G&A.

Production costs were $879,335 in 1999 and $978,080 in 1998, resulting in a
$98,745 decrease, or 10%. The decrease was due to declines in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes due to an
increase in oil and gas revenues.


During this period, G&A increased 36% from $43,488 in 1998 to $58,993 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $46,440 in
1999 and $38,017 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $152,505 and $362,325
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion was $179,801 in 1999 compared to $768,532 in 1998. This represented a
decrease of $588,731, or 77%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 430,250 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with



                                       6
   382


SFAS 121 during the fourth quarter of 1998 and a decline in oil production of
7,716 barrels for the period ended December 31, 1999 compared to the same period
in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $733,136 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $838,001, offset by increases in production costs paid
of $68,104, G&A expenses paid of $20,653, $12,022 in abandoned property costs
paid and working capital of $4,086. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2000 which contributed an
additional $1,065,062 to oil and gas receipts, offset by $227,061 resulting from
the decline in production during 2000. The increase in production costs was
primarily due to increased production taxes associated with higher oil and gas
prices. The increase in G&A was primarily due to higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were for
expenditures related to oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $7,482 recognized during 2000 were related
to salvage income received on one well plugged and abandoned during the current
year. Proceeds of $3,845 recognized during 1999 were primarily from equipment
credits received on one fully depleted well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $1,260,369, of which $317,681
was distributed to the general partners and $942,688 to the limited partners. In
1999, cash distributions to the partners were $438,977, of which $113,074 was
distributed to the general partners and $325,903 to the limited partners.



                                       7
   383


ITEM 8.         FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


                          INDEX TO FINANCIAL STATEMENTS



                                                                                                     Page
                                                                                                     ----
                                                                                                  

Financial Statements of Parker & Parsley 83-B, Ltd:
  Independent Auditors' Report...................................................................      10
  Balance Sheets as of December 31, 2000 and 1999................................................      11
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998..........................................................................      12
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998.............................................................      13
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998..........................................................................      14
  Notes to Financial Statements..................................................................      15





                                       8
   384


                          INDEPENDENT AUDITORS' REPORT




The Partners
Parker & Parsley 83-B, Ltd.
 (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 83-B, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 83-B, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                              Ernst & Young LLP

Dallas, Texas
March 9, 2001



                                       9
   385


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                           2000              1999
                                                       ------------      ------------
                                                                   
   ASSETS
   ------

Current assets:
   Cash                                                $    224,865      $    244,091
   Accounts receivable - oil and gas sales                  369,349           263,774
                                                       ------------      ------------

         Total current assets                               594,214           507,865
                                                       ------------      ------------

Oil and gas properties - at cost, based on the
   successful efforts accounting method                  18,957,070        19,500,569
Accumulated depletion                                   (17,248,214)      (17,616,893)
                                                       ------------      ------------

         Net oil and gas properties                       1,708,856         1,883,676
                                                       ------------      ------------

                                                       $  2,303,070      $  2,391,541
                                                       ============      ============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
   Accounts payable - affiliate                        $     39,862      $     42,935

Partners' capital:
   General partners                                         316,574           309,240
   Limited partners (23,370 interests)                    1,946,634         2,039,366
                                                       ------------      ------------

                                                          2,263,208         2,348,606
                                                       ------------      ------------

                                                       $  2,303,070      $  2,391,541
                                                       ============      ============








   The accompanying notes are an integral part of these financial statements.



                                       10
   386


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                               2000            1999             1998
                                                            -----------     -----------     -----------
                                                                                   

Revenues:
  Oil and gas                                               $ 2,376,791     $ 1,548,013     $ 1,267,241
  Interest                                                       21,343          12,120          13,218
  Gain on disposition of assets                                   7,482           3,375             157
                                                            -----------     -----------     -----------

                                                              2,405,616       1,563,508       1,280,616
                                                            -----------     -----------     -----------

Costs and expenses:
  Oil and gas production                                        947,439         879,335         978,080
  General and administrative                                     79,646          58,993          43,488
  Impairment of oil and gas properties                           84,697         152,505         362,325
  Depletion                                                     106,841         179,801         768,532
  Abandoned property                                             12,022               -               -
                                                            -----------     -----------     -----------

                                                              1,230,645       1,270,634       2,152,425
                                                            -----------     -----------     -----------

Net income (loss)                                           $ 1,174,971     $   292,874     $  (871,809)
                                                            ===========     ===========     ===========

Allocation of net income (loss):
  General partners                                          $   325,015     $   125,187     $   (46,980)
                                                            ===========     ===========     ===========

  Limited partners                                          $   849,956     $   167,687     $  (824,829)
                                                            ===========     ===========     ===========

Net income (loss) per limited partnership interest          $     36.37     $      7.18     $    (35.29)
                                                            ===========     ===========     ===========






   The accompanying notes are an integral part of these financial statements.



                                       11
   387


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                    General          Limited
                                                    partners         partners          Total
                                                  -----------      -----------      -----------
                                                                           

Partners' capital at January 1, 1998              $   435,525      $ 3,290,919      $ 3,726,444

   Distributions                                      (91,418)        (268,508)        (359,926)

   Net loss                                           (46,980)        (824,829)        (871,809)
                                                  -----------      -----------      -----------

Partners' capital at December 31, 1998                297,127        2,197,582        2,494,709

   Distributions                                     (113,074)        (325,903)        (438,977)

   Net income                                         125,187          167,687          292,874
                                                  -----------      -----------      -----------

Partners' capital at December 31, 1999                309,240        2,039,366        2,348,606

   Distributions                                     (317,681)        (942,688)      (1,260,369)

   Net income                                         325,015          849,956        1,174,971
                                                  -----------      -----------      -----------

Partners' capital at December 31, 2000            $   316,574      $ 1,946,634      $ 2,263,208
                                                  ===========      ===========      ===========





   The accompanying notes are an integral part of these financial statements.



                                       12
   388


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                               2000              1999             1998
                                                            -----------      -----------      -----------
                                                                                     

Cash flows from operating activities:
  Net income (loss)                                         $ 1,174,971      $   292,874      $  (871,809)
  Adjustments to reconcile net income (loss)
     to net cash provided by operating activities:
     Impairment of oil and gas properties                        84,697          152,505          362,325
     Depletion                                                  106,841          179,801          768,532
     Gain on disposition of assets                               (7,482)          (3,375)            (157)
  Changes in assets and liabilities:
     Accounts receivable                                       (105,575)        (113,070)          72,320
     Accounts payable                                            (3,073)           8,508          (13,633)
                                                            -----------      -----------      -----------

        Net cash provided by operating activities             1,250,379          517,243          317,578
                                                            -----------      -----------      -----------

Cash flows from investing activities:
  Additions to oil and gas properties                           (16,718)         (11,719)         (27,705)
  Proceeds from disposition of assets                             7,482            3,845           10,974
                                                            -----------      -----------      -----------

        Net cash used in investing activities                    (9,236)          (7,874)         (16,731)
                                                            -----------      -----------      -----------

Cash flows used in financing activities:
  Cash distributions to partners                             (1,260,369)        (438,977)        (359,926)
                                                            -----------      -----------      -----------

Net increase (decrease) in cash                                 (19,226)          70,392          (59,079)
Cash at beginning of year                                       244,091          173,699          232,778
                                                            -----------      -----------      -----------

Cash at end of year                                         $   224,865      $   244,091      $   173,699
                                                            ===========      ===========      ===========





   The accompanying notes are an integral part of these financial statements.


                                       13
   389


                           PARKER & PARSLEY 83-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 83-B, Ltd. (the "Partnership") is a limited partnership
organized in 1983 under the laws of the State of Texas. The Partnership's
general partners are Pioneer Natural Resources USA, Inc. ("Pioneer USA") and P&P
Employees 83-B, Ltd. ("EMPL"). The Partnership's managing general partner is
Pioneer USA.

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited



                                       14
   390


partnership interest is calculated by using the number of outstanding limited
partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non- partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $84,697, $152,505 and
$362,325 related to its proved oil and gas properties during 2000, 1999 and
1998,



                                       15
   391


respectively.

NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $1,137,401 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                               2000             1999              1998
                                                            -----------      -----------      -----------
                                                                                     

Net income (loss) per statements of operations              $ 1,174,971      $   292,874      $  (871,809)
Depletion and depreciation provisions for tax
   reporting purposes less than amounts for
   financial reporting purposes                                  90,760          163,887          749,857
Impairment of oil and gas properties for financial
   reporting purposes                                            84,697          152,505          362,325
Salvage income                                                        -                -              422
Other, net                                                       (7,657)          (1,145)           7,474
                                                            -----------      -----------      -----------

            Net income per Federal income tax
               returns                                      $ 1,342,771      $   608,121      $   248,269
                                                            ===========      ===========      ===========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                            2000               1999            1998
                                         ----------        ----------       ----------
                                                                   

Development costs                        $   16,718        $   11,719       $   27,705
                                         ==========        ==========       ==========


        Capitalized oil and gas properties consist of the following:



                                             2000              1999
                                         ------------      ------------
                                                     

Proved properties:
  Property acquisition costs             $    911,105      $    946,730
  Completed wells and equipment            18,045,965        18,553,839
                                         ------------      ------------

                                           18,957,070        19,500,569
Accumulated depletion                     (17,248,214)      (17,616,893)
                                         ------------      ------------

       Net oil and gas properties        $  1,708,856      $  1,883,676
                                         ============      ============




                                       16
   392


NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999          1998
                                                   ---------     ---------     ---------
                                                                      

Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                    $ 426,573     $ 424,831     $ 426,899

Reimbursement of general and administrative
  expenses                                         $  71,304     $  46,440     $  38,017


        Pioneer USA, EMPL and the Partnership are parties to the partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 79% and the
remaining portion is owned by former affiliates. In addition, Pioneer USA owned
877 limited partner interests at January 1, 2001.

        The costs and revenues of the Partnership are allocated as follows:



                                                               General     Limited
                                                               partners    partners
                                                               --------    --------
                                                                     

Revenues:
  Proceeds from property dispositions prior to cost
     recovery                                                     10%         90%
  All other Partnership revenues                                  25%         75%

Costs and expenses:
  Lease acquisition costs, drilling and completion costs          10%         90%
  Operating costs, direct costs and general and
     administrative expenses                                      25%         75%
  Incremental direct expenses                                      -         100%


        Incremental direct expenses are direct expenses which would not be
incurred except for the requirements of the securities regulatory authorities
and totaled $8,342, $12,553 and $5,471 in 2000, 1999 and 1998, respectively.

NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       17
   393




                                                 Oil and NGLs         Gas
                                                    (bbls)           (mcf)
                                                 ------------     ----------
                                                            

Net proved reserves at January 1, 1998             1,215,076       1,717,779
Revisions                                           (498,218)       (464,099)
Production                                           (93,695)       (147,495)
                                                  ----------      ----------

Net proved reserves at December 31, 1998             623,163       1,106,185
Revisions                                            738,384       1,321,692
Production                                           (89,446)       (157,842)
                                                  ----------      ----------

Net proved reserves at December 31, 1999           1,272,101       2,270,035
Revisions                                             82,614         (66,662)
Production                                           (81,814)       (132,106)
                                                  ----------      ----------

Net proved reserves at December 31, 2000           1,272,901       2,071,267
                                                  ==========      ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.32 per barrel of NGLs and $7.73 per mcf of gas,
discounted at 10% was approximately $9,555,000 and undiscounted was $18,817,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.


                                       18
   394




                                                                         For the years ended December 31,
                                                                      -------------------------------------
                                                                        2000          1999          1998
                                                                      --------      --------      --------
                                                                                (in thousands)
                                                                                         

Oil and gas producing activities:
   Future cash inflows                                                $ 43,776      $ 31,312      $  6,816
   Future production costs                                             (24,959)      (18,234)       (5,169)
                                                                      --------      --------      --------

                                                                        18,817        13,078         1,647
   10% annual discount factor                                           (9,262)       (6,181)         (544)
                                                                      --------      --------      --------

   Standardized measure of discounted future net cash flows           $  9,555      $  6,897      $  1,103
                                                                      ========      ========      ========





                                                             For the years ended December 31,
                                                            ---------------------------------
                                                              2000         1999         1998
                                                            -------      -------      -------
                                                                     (in thousands)
                                                                             

Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs                $(1,429)     $  (669)     $  (289)
  Net changes in prices and production costs                  3,342        3,109       (3,208)
  Revisions of previous quantity estimates                      439        5,091         (627)
  Accretion of discount                                         690          110          489
  Changes in production rates, timing and other                (384)      (1,847)        (147)
                                                            -------      -------      -------

  Change in present value of future net revenues              2,658        5,794       (3,782)
                                                            -------      -------      -------

  Balance, beginning of year                                  6,897        1,103        4,885
                                                            -------      -------      -------

  Balance, end of year                                      $ 9,555      $ 6,897      $ 1,103
                                                            =======      =======      =======


NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                       2000    1999    1998
                                      ------  ------  ------
                                             

Plains Marketing, L.P.                  46%     42%      -
TEPPCO Crude Oil LLC                    13%     14%      -
Phillips Petroleum Company              10%      3%      3%
Genesis Crude Oil, L.P.                  -       -      60%
Western Gas Resources, Inc.              4%      8%     29%


        At December 31, 2000, the amounts receivable from Plains Marketing,
L.P., TEPPCO Crude Oil LLC Inc. and Phillips Petroleum Company were $112,877,
$29,666 and $22,742, respectively, which are included in the caption "Accounts
receivable - oil and gas sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.



                                       19
   395


NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        General partners - The general partners of the Partnership are Pioneer
        USA and EMPL. Pioneer USA, the managing general partner, has the power
        and authority to manage, control and administer all Partnership affairs.
        As managing general partner and operator of the Partnership's
        properties, all production expenses are incurred by Pioneer USA and
        billed to the Partnership. The majority of the Partnership's oil and gas
        revenues are received directly by the Partnership, however, a portion of
        the oil and gas revenue is initially received by Pioneer USA prior to
        being paid to the Partnership.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $23,370,000. The general partners are required to contribute amounts
        equal to 10% of Partnership expenditures for lease acquisition, drilling
        and completion and 25% of direct, general and administrative and
        operating expenses.

ITEM 9.         CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
                 FINANCIAL DISCLOSURE

None.



                                       20
   396


                                    PART III

ITEM 10.        DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                     Age at
                                  December 31,
        Name                          2000                         Position
        ----                          ----                         --------
                                                    

Scott D. Sheffield                     48                 President

Timothy L. Dove                        45                 Executive Vice President, Chief
                                                            Financial Officer and Director

Dennis E. Fagerstone                   51                 Executive Vice President and Director

Mark L. Withrow                        53                 Executive Vice President, General
                                                            Counsel and Director

Danny Kellum                           46                 Executive Vice President - Domestic
                                                            Operations and Director

Rich Dealy                             34                 Vice President and Chief Accounting
                                                            Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   397


        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   398


ITEM 11.        EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. Under the
partnership agreement, Pioneer USA pays 8% of the Program's acquisition,
drilling and completion costs and 20% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 20% of the
Program's revenues.

EMPL is a co-general partner of the Partnership. Under this arrangement, EMPL
pays 2% of the Program's acquisition, drilling and completion costs and 5% of
its operating and general and administrative expenses. In return, EMPL is
allocated 5% of the Program's revenues. EMPL does not receive any fees or
reimbursements from the Partnership.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.        SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)     Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
and EMPL respectively own 80% and 20% of the general partners' interests in the
Partnership. Pioneer USA owned 877 limited partner interests at January 1, 2001.

(b)     Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.


                                       23
   399


ITEM 13.        CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                      2000         1999           1998
                                                   ---------     ---------     ---------
                                                                      

Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                    $ 426,573     $ 424,831     $ 426,899

Reimbursement of general and administrative
  expenses                                         $  71,304     $  46,440     $  38,017


Under the limited partnership agreement, the general partners, Pioneer USA and
EMPL, together pay 10% of the Partnership's acquisition, drilling and completion
costs and 25% of its operating and general and administrative expenses. In
return, they are allocated 25% of the Partnership's revenues. Twenty percent of
the general partners' share of costs and revenues is allocated to EMPL and the
remainder is allocated to Pioneer USA. Certain former affiliates of Pioneer USA
are limited partners of EMPL. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Partnership.



                                       24
   400


                                     PART IV

ITEM 14.        EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                Statements of partners' capital for the years ended December 31,
                   2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   401


                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                 PARKER & PARSLEY 83-B, LTD.

Dated: March 29, 2001            By:   Pioneer Natural Resources USA, Inc.
                                         Managing General Partner


                                       By:   /s/ Scott D. Sheffield
                                             ----------------------------------
                                             Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                                         
/s/ Scott D. Sheffield                      President of Pioneer USA                           March 29, 2001
--------------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                         Executive Vice President, Chief                    March 29, 2001
--------------------------------------      Financial Officer and Director of
Timothy L. Dove                             Pioneer USA


/s/ Dennis E. Fagerstone                    Executive Vice President and                       March 29, 2001
--------------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                         Executive Vice President, General                  March 29, 2001
--------------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                            Executive Vice President - Domestic                March 29, 2001
--------------------------------------      Operations and Director of Pioneer
Danny Kellum                                USA


/s/ Rich Dealy                              Vice President and Chief Accounting                March 29, 2001
--------------------------------------      Officer of Pioneer USA
Rich Dealy




                                       26
   402


                           PARKER & PARSLEY 83-B, LTD.

                                INDEX TO EXHIBITS



        The following documents are incorporated by reference in response to
Item 14(c):



Exhibit No.                               Description                                     Page
-----------                               -----------                                     ----
                                                                                    

    3.1                    Agreement of Limited Partnership of Parker                       -
                           & Parsley 83-B, Ltd. incorporated by reference
                           to Exhibit 4(e) of Partnership's Registration
                           Statement on Form S-1 (Registration No.
                           2-81398B), as amended on April 26, 1983,
                           the effective date thereof (hereinafter called,
                           the Partnership's Registration Statement)

    3.2                    Amended and Restated Certificate of Limited                      -
                           Partnership of Parker & Parsley 83-B, Ltd.
                           incorporated by reference to Exhibit 3.2 of the
                           Partnership's Annual Report on Form 10-K for the
                           period from July 1, 1983 (date of organization)
                           through December 31, 1983

    4.1                    Form of Subscription Agreement and Power of                      -
                           Attorney incorporated by reference to Exhibit 4(b)
                           of the Partnership's Registration Statement

    4.2                    Specimen Certificate of Limited Partnership                      -
                           Interest incorporated by reference to Exhibit 4(d)
                           of the Partnership's Registration Statement





                                       27


   403




                           PARKER & PARSLEY 83-B, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  550,469   $2,376,791   $1,548,013   $1,267,241   $1,924,748   $2,291,605
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $     --   $       --   $       --   $       --   $       --   $       --   $1,392,304
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   84,697   $  152,505   $  362,325   $1,171,409   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  278,602   $1,174,971   $  292,874   $ (871,809)  $ (754,107)  $2,309,638
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         General partners          $          $   73,635   $  325,015   $  125,187   $  (46,980)  $   56,351   $  578,911
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  204,967   $  849,956   $  167,687   $ (824,829)  $ (810,458)  $1,730,727
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per
    limited partnership
    interest                       $          $     8.77   $    36.37   $     7.18   $   (35.29)  $   (34.68)  $    74.06
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per
    limited partnership
    interest                       $          $     8.70   $    40.34   $    13.95   $    11.49   $    32.48   $    80.43(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $2,405,679   $2,303,070   $2,391,541   $2,529,136   $3,774,504   $5,537,639
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $46.83
     in 1996.


   404
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 84-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
84-A, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 84-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-

   405
                           PARKER & PARSLEY 84-A LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $  19,435

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $  28,598

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   3,830
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  201.43

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.77 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

              --  as of March 31, 2001 (c)                                                    $  105.46

              --  as of December 31, 2000 (c)                                                 $  106.99

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  186.82

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  195.53

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     270
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership shall continue until terminated in accordance
with the applicable provisions of its partnership agreement.

                                      -2-

   406



                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                           Commission File No. 2-90417


                           PARKER & PARSLEY 84-A, LTD.
             (Exact name of Registrant as specified in its charter)


                 Texas                                        75-1974814
    ----------------------------------                  ---------------------
     (State or other jurisdiction of                       (I.R.S. Employer
     incorporation or organization)                     Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
             (Address of principal executive offices)               (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.


                                Yes [x] No [ ]


   407



                          PARKER & PARSLEY 84-A, LTD.

                               TABLE OF CONTENTS




                                                                       Page
                                                                 
                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000. . . . ...............................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000............................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001.....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000............................    6

           Notes to Financial Statements..............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations......................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K...........................    9

           Signatures.................................................   10





                                        2
   408



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,     December 31,
                                                       2001           2000
                                                   ------------    ------------
                                                   (Unaudited)
                                                             

                         ASSETS

Current assets:
  Cash                                             $    162,395    $    179,539
  Accounts receivable - oil and gas sales               373,423         360,844
                                                   ------------    ------------
           Total current assets                         535,818         540,383
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method               18,261,069      18,260,776
Accumulated depletion                               (16,419,939)    (16,391,831)
                                                   ------------    ------------
           Net oil and gas properties                 1,841,130       1,868,945
                                                   ------------    ------------
                                                   $  2,376,948    $  2,409,328
                                                   ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $     38,763    $     36,496

Partners' capital:
  General partners                                      288,520         293,504
  Limited partners (19,435 interests)                 2,049,665       2,079,328
                                                   ------------    ------------
                                                      2,338,185       2,372,832
                                                   ------------    ------------
                                                   $  2,376,948    $  2,409,328
                                                   ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

 The accompanying notes are an integral part of these financial statements.




                                        3
   409



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                   Three months ended
                                                        March 31,
                                                 -----------------------
                                                    2001         2000
                                                 ----------   ----------
                                                        

Revenues:
  Oil and gas                                    $  634,643   $  533,060
  Interest                                            3,655        2,698
                                                 ----------   ----------
                                                    638,298      535,758
                                                 ----------   ----------
Costs and expenses:
  Oil and gas production                            248,790      219,634
  General and administrative                         22,219       14,335
  Depletion                                          28,108       33,646
                                                 ----------   ----------
                                                    299,117      267,615
                                                 ----------   ----------
Net income                                       $  339,181   $  268,143
                                                 ==========   ==========
Allocation of net income:
  General partners                               $   89,466   $   72,174
                                                 ==========   ==========
  Limited partners                               $  249,715   $  195,969
                                                 ==========   ==========
Net income per limited partnership interest      $    12.85   $    10.08
                                                 ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.




                                        4

   410



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                    General         Limited
                                    partners        partners         Total
                                  ------------    ------------    ------------
                                                         

Balance at January 1, 2001        $    293,504    $  2,079,328    $  2,372,832

   Distributions                       (94,450)       (279,378)       (373,828)

   Net income                           89,466         249,715         339,181
                                  ------------    ------------    ------------

Balance at March 31, 2001         $    288,520    $  2,049,665    $  2,338,185
                                  ============    ============    ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5
   411



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                           Three months ended
                                                               March 31,
                                                        ------------------------
                                                           2001          2000
                                                        ----------    ----------
                                                                
Cash flows from operating activities:
  Net income                                            $  339,181    $  268,143
  Adjustments to reconcile net income to net
     cash provided by operating activities:
       Depletion                                            28,108        33,646
  Changes in assets and liabilities:
     Accounts receivable                                   (12,579)      (15,188)
     Accounts payable                                        2,267         6,873
                                                        ----------    ----------
        Net cash provided by operating activities          356,977       293,474
                                                        ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                         (293)       (5,060)

Cash flows used in financing activities:
  Cash distributions to partners                          (373,828)     (215,712)
                                                        ----------    ----------
Net increase (decrease) in cash                            (17,144)       72,702
Cash at beginning of period                                179,539       117,140
                                                        ----------    ----------
Cash at end of period                                   $  162,395    $  189,842
                                                        ==========    ==========





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        6
   412


                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 84-A, Ltd. (the "Partnership") is a limited partnership
organized in 1984 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 19% to $634,643 for the three
months ended March 31, 2001 as compared to $533,060 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 13,629
barrels of oil, 6,391 barrels of natural gas liquids ("NGLs") and 33,550 mcf of
gas were sold, or 25,612 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 13,571 barrels of oil, 8,220 barrels of NGLs and
35,071 mcf of gas were sold, or 27,636 BOEs.



                                        7
   413


The average price received per barrel of oil decreased $.45, or 2%, from $27.61
for the three months ended March 31, 2000 to $27.16 for the same period in 2001.
The average price received per barrel of NGLs increased $3.50, or 28%, from
$12.70 for the three months ended March 31, 2000 to $16.20 for the same period
in 2001. The average price received per mcf of gas increased 212% from $1.54
during the three months ended March 31, 2000 to $4.80 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $299,117 for the three months ended March
31, 2001 as compared to $267,615 for the same period in 2000, an increase of
$31,502, or 12%. This increase was primarily due to increases in production
costs and general and administrative expenses ("G&A"), offset by a decline in
depletion.

Production costs were $248,790 for the three months ended March 31, 2001 and
$219,634 for the same period in 2000 resulting in a $29,156 increase, or 13%.
The increase was primarily due to additional well maintenance costs incurred to
stimulate well production and higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 55% from $14,335 for the three months ended March 31, 2000 to $22,219
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $28,108 for the three months ended March 31, 2001 as compared to
$33,646 for the same period in 2000, a decrease of $5,538, or 16%. This decrease
was the result of positive revisions to proved reserves during the three months
ended March 31, 2001 as a result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $63,503 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to an increase of $102,540 in oil and gas sales receipts, offset by increases in
production costs of $29,156, G&A expenses of $7,884 and working capital of
$1,997. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2001 which contributed an additional $137,887 to oil and
gas receipts, offset by $35,347 resulting from the decline in production during
2001 as compared to the same period in 2000. The increase in production costs
was primarily due to additional well maintenance costs incurred to stimulate
well production and increased production taxes associated with higher oil and



                                        8
   414



gas prices. The increase in G&A was primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 were for expenditures related to oil and gas equipment
upgrades on active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $373,828, of which $94,450 was distributed to the general partners and
$279,378 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $215,712, of which $54,767 was distributed to
the general partners and $160,945 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.

                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)   Exhibits - none

(b)   Reports on Form 8-K - none.



                                        9
   415


                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                             PARKER & PARSLEY 84-A, LTD.



                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 10, 2001                By:     /s/ Rich Dealy
                                            ---------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer








                                       10



   416
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                           COMMISSION FILE NO. 2-90417


                           PARKER & PARSLEY 84-A, LTD.
             (Exact name of Registrant as specified in its charter)


                                                                       
                            TEXAS                                                  75-1974814
         ------------------------------------------                       ---------------------------
         (State or other jurisdiction of                                     (I.R.S. Employer
         incorporation or organization)                                   Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                      75039
----------------------------------------------------------------                  -------------
         (Address of principal executive offices)                                   (Zip code)



       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES \ X \ NO \ \

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. \ X \

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-s of the Registrant is $19,016,000.

           As of March 8, 2001, the number of outstanding limited partnership
interests was 19,435.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


                                       2
   417

                                     PART I

ITEM 1.        BUSINESS

Parker & Parsley 84-A, Ltd. (the "Partnership") is a limited partnership
organized in 1984 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA")
and its co-general partner is P&P Employees 84-A, Ltd. ("EMPL"), a Texas limited
partnership whose general partner is Pioneer USA. Pioneer USA is a wholly-owned
subsidiary of Pioneer Natural Resources Company ("Pioneer"). As of March 8,
2001, the Partnership had 19,435 limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000, approximately 35%, 17% and 10% were attributable to sales
made to Plains Marketing, L.P., TEPPCO Crude Oil LLC and NGTS LLC, respectively.
Pioneer USA is of the opinion that the loss of any one purchaser would not have
an adverse effect on its ability to sell its oil, natural gas liquids ("NGLs")
and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations. The oil and gas business is
also subject to environmental hazards such as oil spills, gas leaks and ruptures
and discharges of toxic substances or gases that could expose the Partnership to
substantial




                                       2
   418

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.        PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental and exploratory oil and gas
prospects located primarily in the Spraberry Trend Area of West Texas were
acquired by the Partnership, resulting in the Partnership's participation in the
drilling of 42 oil and gas wells. At December 31, 2000, 38 wells were producing
and four wells had been plugged and abandoned due to unprofitable operations.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.        LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.        SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.




                                       3
   419


                                     PART II

ITEM 5.        MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                 DISTRIBUTIONS

At March 8, 2001, the Partnership had 19,435 outstanding limited partnership
interests held of record by 1,268 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $872,006 and
$293,145, respectively, were made to the limited partners.

ITEM 6.        SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                     2000          1999        1998            1997       1996
                                  -----------   ----------   ----------    ----------  ----------
Operating results:
-----------------
                                                                         
 Oil and gas sales                $2,348,261    $1,419,376   $1,124,134    $1,668,018   $1,984,346
                                   =========     =========    =========     =========    =========

 Impairment of oil and gas
    properties                    $      -      $      -      $  425,668   $  370,361   $      -
                                   =========     =========     =========    =========    =========

 Gain on litigation
    settlement, net               $      -      $      -      $      -     $      -     $1,055,353
                                   =========     =========     =========    =========    =========

 Net income (loss)                $1,240,674    $  340,062    $ (923,346)  $   70,124   $1,782,138
                                   =========     =========     =========    =========    =========

 Allocation of net income
    (loss):
      General partners            $  328,079    $  113,550    $  (56,570)  $  121,907   $  462,041
                                   =========     =========     =========    =========    =========

      Limited partners            $  912,595    $  226,512    $ (866,776)  $  (51,783)  $1,320,097
                                   =========     =========     =========    =========    =========

 Limited partners' net income
    (loss) per limited
    partnership interest          $    46.96    $    11.65    $   (44.60)  $   (2.66)   $    67.92
                                   =========     =========     =========    =========    =========

 Limited partners' cash
    distributions per limited
    partnership interest          $    44.87    $    15.08    $    12.82   $    32.32    $   73.68 (a)
                                   =========    ==========     =========    =========     ========

At year end:
-----------
 Identifiable assets              $2,409,328    $2,343,035    $2,390,810   $3,657,643   $4,436,385
                                   =========     =========     =========    =========    =========

---------------

(a) Including litigation settlement per limited partnership interest of $42.48
    in 1996.



                                       4
   420



ITEM 7.        MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                 RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 65% to $2,348,261 for 2000 as
compared to $1,419,376 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 51,863
barrels of oil, 33,622 barrels of natural gas liquids ("NGLs") and 138,617 mcf
of gas were sold, or 108,588 barrel of oil equivalents ("BOEs"). In 1999, 50,064
barrels of oil, 35,804 barrels of NGLs and 154,235 mcf of gas were sold, or
111,574 BOEs. Due to the decline characteristics of the Partnership's oil and
gas properties, management expects a certain amount of decline in production in
the future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.19, or 70%, from
$17.36 in 1999 to $29.55 in 2000. The average price received per barrel of NGLs
increased $4.97, or 55%, from $9.03 in 1999 to $14.00 in 2000. The average price
received per mcf of gas increased 69% from $1.47 in 1999 to $2.49 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility in the foreseeable future. The
Partnership may therefore sell its future oil and gas production at average
prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $1,124,923 as compared to
$1,088,550 in 1999, an increase of $36,373, or 3%. The increase was primarily
due to increases in production costs and general and administrative expenses
("G&A"), offset by a decline in depletion.

Production costs were $937,743 in 2000 and $859,602 in 1999, resulting in an
increase of $78,141 or 9%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and workover costs incurred to
stimulate well production, offset by lower well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
45% from $53,481 in 1999 to $77,459 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $70,448 in 2000 and $42,581 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   421



Depletion was $109,721 in 2000 as compared to $175,467 in 1999, representing a
decrease of $65,746, or 37%. This decrease was primarily due to a 150,475
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 26% to $1,419,376 from
$1,124,134 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 50,064 barrels of oil,
35,804 barrels of NGLs and 154,235 mcf of gas were sold, or 111,574 BOEs. In
1998, 54,153 barrels of oil, 34,549 barrels of NGLs and 145,870 mcf of gas were
sold, or 113,014 BOEs.

The average price received per barrel of oil increased $4.06, or 31%, from
$13.30 in 1998 to $17.36 in 1999. The average price received per barrel of NGLs
increased $2.95, or 49%, from $6.08 in 1998 to $9.03 in 1999. The average price
received per mcf of gas increased 11% from $1.33 in 1998 to $1.47 in 1999.

A gain on disposition of assets of $2,100 was recognized during 1998 from the
sale of equipment on one fully depleted well.

Total costs and expenses decreased in 1999 to $1,088,550 as compared to
$2,059,738 in 1998, a decrease of $971,188, or 47%. The decrease was primarily
due to declines in depletion, the impairment of oil and gas properties and
production costs, offset by an increase in G&A expenses.

Production costs were $859,602 in 1999 and $865,247 in 1998, resulting in a
$5,645 decrease. The decrease was due to declines in workover costs and ad
valorem taxes, offset by increases in well maintenance costs incurred to
stimulate well production and in production taxes due to increased oil and gas
revenues.

During this period, G&A increased 39% from $38,385 in 1998 to $53,481 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $42,581 in
1999 and $33,724 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $425,668 related to its oil and gas properties during 1998.

Depletion was $175,467 in 1999 compared to $730,438 in 1998. This represented a
decrease of $554,971, or 76%. This decrease was the result of an increase in
proved reserves of 445,239 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.



                                       6
   422



Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $852,554 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $936,985 and a decline in working capital of $17,688,
offset by increases in production costs paid of $78,141 and G&A expenses paid of
$23,978. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2000 which contributed an additional $953,265 to oil and
gas receipts, offset by $16,280 resulting from the decline in production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices and workover costs incurred to
stimulate well production, offset by lower well maintenance costs. The increase
in G&A was primarily due to higher percentage of the managing general partner's
G&A being allocated (limited to 3% of oil and gas revenues) as a result of
increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for equipment upgrades on various oil and gas properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $1,173,468, of which $301,462
was distributed to the general partners and $872,006 to the limited partners. In
1999, cash distributions to the partners were $392,295, of which $99,150 was
distributed to the general partners and $293,145 to the limited partners.



                                       7
   423


ITEM 8.        FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA



                          INDEX TO FINANCIAL STATEMENTS


                                                                                         Page

                                                                                    
Financial Statements of Parker & Parsley 84-A, Ltd:
 Independent Auditors' Report.........................................................     9
 Balance Sheets as of December 31, 2000 and 1999......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14






                                       8
   424





                          INDEPENDENT AUDITORS' REPORT




The Partners
Parker & Parsley 84-A, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 84-A, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 84-A, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.


                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001



                                       9
   425



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                        2000           1999
                                                   -------------   -------------
              ASSETS
              ------
                                                             
Current assets:
  Cash                                             $    179,539    $    117,140
  Accounts receivable - oil and gas sales               360,844         261,763
                                                   ------------    ------------

       Total current assets                             540,383         378,903
                                                   ------------    ------------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               18,260,776      18,246,242
Accumulated depletion                               (16,391,831)    (16,282,110)
                                                   ------------    ------------

       Net oil and gas properties                     1,868,945       1,964,132
                                                   ------------    ------------

                                                   $  2,409,328    $  2,343,035
                                                   ============    ============


LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable -                               $     36,496    $     37,409

Partners' capital:
  General partners                                      293,504         266,887
  Limited partners (19,435 interests)                 2,079,328       2,038,739
                                                   ------------    ------------

                                                      2,372,832       2,305,626
                                                   ------------    ------------

                                                   $  2,409,328    $  2,343,035
                                                   ============    ============

















   The accompanying notes are an integral part of these financial statements.



                                       10
   426



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                             2000         1999          1998
                                        -----------   -----------   -----------
                                                           
Revenues:
 Oil and gas                            $ 2,348,261   $ 1,419,376   $ 1,124,134
 Interest                                    17,336         9,236        10,158
 Gain on disposition of assets                   --            --         2,100
                                        -----------   -----------   -----------

                                          2,365,597     1,428,612     1,136,392
                                        -----------   -----------   -----------

Costs and expenses:
 Oil and gas production                     937,743       859,602       865,247
 General and administrative                  77,459        53,481        38,385
 Impairment of oil and gas properties            --            --       425,668
 Depletion                                  109,721       175,467       730,438
                                        -----------   -----------   -----------

                                          1,124,923     1,088,550     2,059,738
                                        -----------   -----------   -----------

Net income (loss)                       $ 1,240,674   $   340,062   $  (923,346)
                                        ===========   ===========   ===========

Allocation of net income (loss):
 General partners                       $   328,079   $   113,550   $   (56,570)
                                        ===========   ===========   ===========

 Limited partners                       $   912,595   $   226,512   $  (866,776)
                                        ===========   ===========   ===========

Net income (loss) per limited
 partnership interest                   $     46.96   $     11.65   $    (44.60)
                                        ===========   ===========   ===========




















   The accompanying notes are an integral part of these financial statements.



                                       11
   427



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                           General       Limited
                                           partners      partners         Total
                                         -----------    -----------    -----------


                                                              
Partners' capital at January 1, 1998     $   395,245    $ 3,221,215    $ 3,616,460

   Distributions                             (86,188)      (249,067)      (335,255)

   Net loss                                  (56,570)      (866,776)      (923,346)
                                         -----------    -----------    -----------

Partners' capital at December 31, 1998       252,487      2,105,372      2,357,859

   Distributions                             (99,150)      (293,145)      (392,295)

   Net income                                113,550        226,512        340,062
                                         -----------    -----------    -----------

Partners' capital at December 31, 1999       266,887      2,038,739      2,305,626

   Distributions                            (301,462)      (872,006)    (1,173,468)

   Net income                                328,079        912,595      1,240,674
                                         -----------    -----------    -----------

Partners' capital at December 31, 2000   $   293,504    $ 2,079,328    $ 2,372,832
                                         ===========    ===========    ===========
























   The accompanying notes are an integral part of these financial statements.



                                       12
   428


                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                        2000          1999           1998
                                                   -------------    -----------    -----------
                                                                          
Cash flows from operating activities:
  Net income (loss)                                  $ 1,240,674    $   340,062    $  (923,346)
  Adjustments to reconcile net income (loss)  to
    net cash provided by operating activities:
      Impairment of oil and gas properties                    --             --        425,668
      Depletion                                          109,721        175,467        730,438
      Gain on disposition of assets                           --             --         (2,100)
  Changes in assets and liabilities:
      Accounts receivable                                (99,081)      (122,140)        85,609
      Accounts payable                                      (913)         4,458         (8,232)
                                                     -----------    -----------    -----------

         Net cash provided by operating activities     1,250,401        397,847        308,037
                                                     -----------    -----------    -----------

Cash flows from investing activities:
  Additions to oil and gas properties                    (14,534)       (12,628)       (10,572)
  Proceeds from asset dispositions                            --            211          2,100
                                                     -----------    -----------    -----------

         Net cash used in investing activities           (14,534)       (12,417)        (8,472)
                                                     -----------    -----------    -----------

Cash flows used in financing activities:
  Cash distributions to partners                      (1,173,468)      (392,295)      (335,255)
                                                     -----------    -----------    -----------

Net increase (decrease) in cash                           62,399         (6,865)       (35,690)
Cash at beginning of year                                117,140        124,005        159,695
                                                     -----------    -----------    -----------

Cash at end of year                                  $   179,539    $   117,140    $   124,005
                                                     ===========    ===========    ===========

















   The accompanying notes are an integral part of these financial statements.



                                       13
   429



                           PARKER & PARSLEY 84-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.        ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 84-A, Ltd. (the "Partnership") is a limited partnership
organized in 1984 under the laws of the State of Texas. The Partnership's
general partners are Pioneer Natural Resources USA, Inc. ("Pioneer USA") and P&P
Employees 84-A, Ltd. ("EMPL"). The Partnership's managing general partner is
Pioneer USA.

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.        SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements



                                       14
   430

as the income of the Partnership is included in the individual Federal income
tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.        IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $425,668 related to
its proved oil and gas properties during 1998.



                                       15
   431

NOTE 4.        INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $383,897 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                 2000          1999           1998
                                                            -----------    -----------    -----------

                                                                                 
Net income (loss) per statements of operations              $ 1,240,674    $   340,062    $  (923,346)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                                   98,611        165,764        695,743
Impairment of oil and gas properties for financial
  reporting purposes                                                 --             --        425,668
Salvage income                                                       --             --          2,967
Other, net                                                       (2,689)        (4,938)         5,121
                                                            -----------    -----------    -----------

       Net income per Federal income tax
         returns                                            $ 1,336,596    $   500,888    $   206,153
                                                            ===========    ===========    ===========


NOTE 5.        OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                   ---------     ----------     ---------
                                                                       
    Development costs                              $  14,534     $   12,628     $  10,572
                                                   =========     ==========     =========



      Capitalized oil and gas properties consist of the following:



                                        2000            1999
                                    ------------    ------------
                                              
Proved properties:
  Property acquisition costs        $    923,276    $    923,276
  Completed wells and equipment       17,337,500      17,322,966
                                    ------------    ------------

                                      18,260,776      18,246,242
Accumulated depletion                (16,391,831)    (16,282,110)
                                    ------------    ------------

       Net oil and gas properties   $  1,868,945    $  1,964,132
                                    ============    ============







                                       16
   432



NOTE 6.        RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999          1998
                                                   ---------     ----------     ---------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 410,572     $  395,016     $ 382,325

    Reimbursement of general and administrative
      expenses                                     $  70,448     $   42,581     $  33,724



      Pioneer USA, EMPL and the Partnership are parties to the Partnership
agreement. EMPL is a limited partnership in which Pioneer USA owns 77.5% and the
remaining portion is owned by former s. In addition, Pioneer USA owned 419
limited partner interests in the Partnership at January 1, 2001.

      The costs and revenues of the Partnership are allocated as follows:



                                                              General           Limited
                                                              partners          partners
                                                              --------          --------
                                                                         
  Revenues:
    Proceeds from property dispositions prior to cost
      recovery                                                    10%              90%
    All other Partnership revenues                                25%              75%

  Costs and expenses:
    Lease acquisition costs, drilling and completion costs        10%              90%
    Operating costs, direct costs and general and
      administrative expenses                                     25%              75%
    Incremental direct expenses                                    -              100%



        Incremental direct expenses are direct expenses which would not be
incurred except for the requirements of the securities regulatory authorities
and totaled $7,011, $10,900 and $4,661 in 2000, 1999 and 1998, respectively.

NOTE 7.        OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                       17
   433





                                          Oil and NGLs       Gas
                                             (bbls)         (mcf)
                                          ------------   ----------

                                                   
Net proved reserves at January 1, 1998      1,053,041     1,516,688
Revisions                                    (400,628)     (306,319)
Production                                    (88,702)     (145,870)
                                           ----------    ----------

Net proved reserves at December 31, 1998      563,711     1,064,499
Revisions                                     789,038     1,498,169
Production                                    (85,868)     (154,235)
                                           ----------    ----------

Net proved reserves at December 31, 1999    1,266,881     2,408,433
Revisions                                     168,380       (31,965)
Production                                    (85,485)     (138,617)
                                           ----------    ----------

Net proved reserves at December 31, 2000    1,349,776     2,237,851
                                           ==========    ==========



        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.02 per barrel of NGLs and $7.45 per mcf of gas,
discounted at 10% was approximately $10,236,000 and undiscounted was
$20,832,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                       18
   434




                                                             For the years ended December 31,
                                                             --------------------------------
                                                               2000        1999        1998
                                                             --------    --------    --------
                                                                      (in thousands)
                                                                            
Oil and gas producing activities:
  Future cash inflows                                        $ 45,297    $ 30,875    $  6,111
  Future production costs                                     (24,465)    (18,195)     (4,514)
                                                             --------    --------    --------

                                                               20,832      12,680       1,597
  10% annual discount factor                                  (10,596)     (6,020)       (598)
                                                             --------    --------    --------

  Standardized measure of discounted future net cash flows   $ 10,236    $  6,660    $    999
                                                             ========    ========    ========





                                                   For the years ended December 31,
                                                   --------------------------------
                                                     2000        1999        1998
                                                   --------    --------    --------
                                                            (in thousands)
                                                                
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs       $ (1,411)   $   (560)   $   (259)
  Net changes in prices and production costs          3,988       2,450      (2,438)
  Revisions of previous quantity estimates            1,037       4,939        (555)
  Accretion of discount                                 666         100         406
  Changes in production rates, timing and other        (704)     (1,268)       (211)
                                                   --------    --------    --------

  Change in present value of future net revenues      3,576       5,661      (3,057)
                                                   --------    --------    --------

  Balance, beginning of year                          6,660         999       4,056
                                                   --------    --------    --------

  Balance, end of year                             $ 10,236    $  6,660    $    999
                                                   ========    ========    ========



NOTE 8.        MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                   2000          1999           1998
                                                 --------      --------       --------

                                                                       
           Plains Marketing, L.P.                  35%             33%            -
           TEPPCO Crude Oil LLC                    17%             18%            -
           Genesis Crude Oil, L.P.                  -               -            53%
           NGTS LLC                                10%              7%            -
           Western Gas Resources, Inc.              3%              7%           29%



        At December 31, 2000, the amounts receivable from Plains Marketing,
L.P., TEPPCO Crude Oil LLC and NGTS LLC were $43,117, $76,863 and $693,
respectively, which are included in the caption "Accounts receivable - oil and
gas sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.        PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:



        General partners - The general partners of the Partnership are Pioneer
        USA and EMPL. Pioneer USA, the managing general partner, has the power
        and authority to manage, control and administer all Partnership affairs.
        As managing general partner and operator of the Partnership's
        properties, all production expenses are incurred by Pioneer USA and
        billed to the Partnership. The majority of the Partnership's oil and gas
        revenues are received directly by the Partnership, however, a portion of
        the oil and gas revenue is initially received by Pioneer USA prior to
        being paid to the Partnership.



                                       19
   435

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $19,435,000. The general partners are required to contribute amounts
        equal to 10% of Partnership expenditures for lease acquisition, drilling
        and completion and 25% of direct, general and administrative and
        operating expenses.

ITEM 9.        CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                 AND FINANCIAL DISCLOSURE

None.


                                       20
   436


                                    PART III

ITEM 10.       DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                     December 31,
       Name                             2000                       Position
       ----                             ----                       --------
                                                 
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer



        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   437


        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   438


ITEM 11.       EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. Under the
Partnership agreement, Pioneer USA pays 8% of the Partnership's acquisition,
drilling and completion costs and 20% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 20% of the
Partnership's revenues.

EMPL is a co-general partner of the Partnership. Under this arrangement, EMPL
pays 2% of the Partnership's acquisition, drilling and completion costs and 5%
of its operating and general and administrative expenses. In return, EMPL is
allocated 5% of the Partnership's revenues. EMPL does not receive any fees or
reimbursements from the Partnership.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.       SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)     Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
and EMPL respectively own 80% and 20% of the general partners' interests in the
Partnership. Pioneer USA owned 419 limited partner interests at January 1, 2001.

(b)     Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.



                                       23
   439


ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                2000       1999       1998
                                              --------   --------   ---------

Payment of lease operating and supervision
  charges in accordance with standard
                                                           
  industry operating agreements               $410,572   $395,016   $382,325

Reimbursement of general and administrative
  expenses                                    $ 70,448   $ 42,581   $ 33,724



Under the limited partnership agreement, the general partners, Pioneer USA and
EMPL, together pay 10% of the Partnership's acquisition, drilling and completion
costs and 25% of its operating and general and administrative expenses. In
return, they are allocated 25% of the Partnership's revenues. Twenty percent of
the general partners' share of costs and revenues is allocated to EMPL and the
remainder is allocated to Pioneer USA. Certain former s of Pioneer USA are
limited partners of EMPL. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Partnership.




                                       24
   440


                                     PART IV

ITEM 14.       EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)  1.   Financial statements

          The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                Statements of partners' capital for the years ended December 31,
                   2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                Notes to financial statements

     2.   Financial statement schedules

          All financial statement schedules have been omitted since the
          required information is in the financial statements or notes thereto,
          or is not applicable nor required.

(b)  Reports on Form 8-K

None.

(c)  Exhibits

     The exhibits listed on the accompanying index to exhibits are filed or
     incorporated by reference as part of this Report.



                                       25
   441



                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 84-A, LTD.

Dated: March 23, 2001               By:   Pioneer Natural Resources USA, Inc.
                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                -------------------------------
                                                Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 23, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 23, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 23, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 23, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 23, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 23, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy



   442


                           PARKER & PARSLEY 84-A, LTD.

                                INDEX TO EXHIBITS


      The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----
                                                                        
     3.1                  Agreement of limited partnership of Parker                -
                          & Parsley 84-A, Ltd. incorporated by reference
                          to Exhibit 4(e) of Partnership's Registration
                          Statement on Form S-1 (Registration No.
                          2-90417), as amended on May 24, 1984, the
                          effective date thereof (hereinafter called, the
                          Partnership's Registration Statement)

     3.2                  Amended and Restated Certificate of Limited               -
                          Partnership of Parker & Parsley 84-A, Ltd.
                          incorporated by reference to Exhibit 3.2 of the
                          Partnership's Annual Report on Form 10-K for
                          the period from July 6, 1984 (date of organization)
                          through December 31, 1984

     4.1                  Form of Subscription Agreement and Power of               -
                          Attorney incorporated by reference to Exhibit 4(b)
                          of the Partnership's Registration Statement

     4.2                  Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit 4(d)
                          of the Partnership's Registration Statement













   443




                           PARKER & PARSLEY 84-A, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  533,060   $2,348,261   $1,419,376   $1,124,134   $1,668,018   $1,984,346
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
    properties                     $          $       --   $       --   $       --   $  425,668   $  370,361   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $     --   $       --   $       --   $       --   $       --   $       --   $1,055,353
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  268,143   $1,240,674   $  340,062   $ (923,346)  $   70,124   $1,782,138
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
         General partners          $          $   72,174   $  328,079   $  113,550   $  (56,570)  $  121,907   $  462,041
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  195,969   $  912,595   $  226,512   $ (866,776)  $  (51,783)  $1,320,097
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
    (loss) per limited
    partnership interest           $          $    10.08   $    46.96   $    11.65   $   (44.60)  $    (2.66)  $    67.92
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $     8.28   $    44.87   $    15.08   $    12.82   $    32.32   $    73.68(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $2,402,339   $2,409,328   $2,343,035   $2,390,810   $3,657,643   $4,436,385
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $42.48
     in 1996.



   444
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 85-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
85-A, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 85-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-

   445
                           PARKER & PARSLEY 85-A LTD.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $   9,613

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   7,280

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   1,363
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  144.55

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.27 times
past four quarterly distributions including the distribution in July 2001 (b) (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $   69.75

          --  as of December 31, 2000 (c)                                                     $   71.31

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  132.31

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  140.34

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     260
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent the
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2035, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   446

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 2-99079A


                           PARKER & PARSLEY 85-A, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                                  75-2064518
          ----------------------------------            ---------------------
           (State or other jurisdiction of                  (I.R.S. Employer
           incorporation or organization)               Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas     75039
----------------------------------------------------------------   ----------
            (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]   No [ ]





   447



                           PARKER & PARSLEY 85-A, LTD.

                                TABLE OF CONTENTS




                                                                         Page

                                                                         
                          Part I. Financial Information

Item 1.      Financial Statements

             Balance Sheets as of March 31, 2001 and
                December 31, 2000.......................................    3

             Statements of Operations for the three months
               ended March 31, 2001 and 2000............................    4

             Statement of Partners' Capital for the three months
               ended March 31, 2001.....................................    5

             Statements of Cash Flows for the three months
               ended March 31, 2001 and 2000............................    6

             Notes to Financial Statements..............................    7

Item 2.      Management's Discussion and Analysis of Financial
               Condition and Results of Operations......................    7


                        Part II. Other Information

Item 6.      Exhibits and Reports on Form 8-K...........................    9

             Signatures.................................................   10




                                        2

   448



                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,      December 31,
                                                       2001            2000
                                                    -----------     ------------
                                                    (Unaudited)
                       ASSETS

                                                              
Current assets:
   Cash                                             $    59,915     $    72,868
   Accounts receivable - oil and gas sales              111,661         103,810
                                                    -----------     -----------
           Total current assets                         171,576         176,678
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
   successful efforts accounting method               7,400,903       7,398,954
Accumulated depletion                                (6,880,442)     (6,871,985)
                                                    -----------     -----------
           Net oil and gas properties                   520,461         526,969
                                                    -----------     -----------
                                                    $   692,037     $   703,647
                                                    ===========     ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable - affiliate                     $    14,772     $    11,211

Partners' capital:
   Managing general partner                               6,785           6,936
   Limited partners (9,613 interests)                   670,480         685,500
                                                    -----------     -----------
                                                        677,265         692,436
                                                    -----------     -----------
                                                    $   692,037     $   703,647
                                                    ===========     ===========



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   449



                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                         Three months ended
                                                              March 31,
                                                      -------------------------
                                                         2001           2000
                                                      ----------     ----------
                                                               

Revenues:
   Oil and gas                                        $  216,806     $  178,428
   Interest                                                1,318          1,030
                                                      ----------     ----------
                                                         218,124        179,458
                                                      ----------     ----------
Costs and expenses:
   Oil and gas production                                 85,302         91,946
   General and administrative                              6,504          5,353
   Depletion                                               8,457          8,592
                                                      ----------     ----------
                                                         100,263        105,891
                                                      ----------     ----------
Net income                                            $  117,861     $   73,567
                                                      ==========     ==========
Allocation of net income:
   Managing general partner                           $    1,179     $      736
                                                      ==========     ==========
   Limited partners                                   $  116,682     $   72,831
                                                      ==========     ==========
Net income per limited partnership interest           $    12.14     $     7.58
                                                      ==========     ==========





         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        4

   450

                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                         Managing
                                         general      Limited
                                         partner      partners       Total
                                        ---------    ----------    ----------


                                                          
Balance at January 1, 2001              $   6,936    $  685,500    $  692,436

   Distributions                           (1,330)     (131,702)     (133,032)

   Net income                               1,179       116,682       117,861
                                        ---------    ----------    ----------

Balance at March 31, 2001               $   6,785    $  670,480    $  677,265
                                        =========    ==========    ==========






         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   451
                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                          Three months ended
                                                              March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------

                                                               
Cash flows from operating activities:
  Net income                                           $  117,861    $   73,567
  Adjustments to reconcile net income to net
     cash provided by operating activities:
       Depletion                                            8,457         8,592
  Changes in assets and liabilities:
     Accounts receivable                                   (7,851)       (6,591)
     Accounts payable                                       3,561         1,383
                                                       ----------    ----------
         Net cash provided by operating activities        122,028        76,951
                                                       ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                      (1,949)       (3,092)
Cash flows used in financing activities:
  Cash distributions to partners                         (133,032)      (68,884)
                                                       ----------    ----------
Net increase (decrease) in cash                           (12,953)        4,975
Cash at beginning of period                                72,868        73,810
                                                       ----------    ----------
Cash at end of period                                  $   59,915    $   78,785
                                                       ==========    ==========





         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   452



                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 85-A, Ltd. (the "Partnership") is a limited partnership
organized in 1985 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 22% to $216,806 for the three
months ended March 31, 2001 to $178,428 for the same period in 2000. The
increase in revenues resulted from higher average prices received, offset by a
decrease in production. For the three months ended March 31, 2001, 4,034 barrels
of oil, 2,018 barrels of natural gas liquids ("NGLs") and 12,365 mcf of gas were
sold, or 8,113 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 4,451 barrels of oil, 2,984 barrels of NGLs and 11,812 mcf of
gas were sold, or 9,404 BOEs.

                                        7

   453



The average price received per barrel of oil increased $.89, or 3%, from $27.40
for the three months ended March 31, 2000 to $28.29 for the same period in 2001.
The average price received per barrel of NGLs increased $5.52, or 45%, from
$12.16 for the three months ended March 31, 2000 to $17.68 for the same period
in 2001. The average price received per mcf of gas increased 217% from $1.71
during the three months ended March 31, 2000 to $5.42 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses decreased to $100,263 for the three months ended March
31, 2001 as compared to $105,891 for the same period in 2000, a decrease of
$5,628, or 5%. This decrease was due to decreases in production costs and
depletion, offset by an increase in general and administrative expenses ("G&A").

Production costs were $85,302 for the three months ended March 31, 2001 and
$91,946 for the same period in 2000, a decrease of $6,644, or 7%. The decrease
was primarily due to a decrease in well maintenance costs, offset by higher
production taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 22% from $5,353 for the three months ended March 31, 2000 to $6,504
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $8,457 for the three months ended March 31, 2001 as compared to
$8,592 for the same period in 2000, a decrease of $135, or 2%. This decrease was
primarily due to a decline in oil production of 417 barrels for the period ended
March 31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $45,077 for the three months
ended March 31, 2001 from the same period in 2000. The increase was primarily
attributable to an increase of $38,666 in oil and gas sales receipts and
reductions in production costs of $6,644 and working capital of $918, offset by
an increase in G&A expenses of $1,151. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $64,539 to oil and gas receipts, offset by $25,873 resulting from the
decline in production during 2001. The decrease in production costs was
primarily due to a decline in well maintenance costs, offset by increased
production taxes associated with higher oil and gas prices. The increase in G&A
was primarily due to an increase in the accrual for tax preparation fees.

                                        8

   454



Net Cash Used in Investing Activities

The Partnership's investing activities during the three months ended March 31,
2001 and 2000 were related to equipment upgrades on active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $133,032, of which $1,330 was distributed to the managing general partner
and $131,702 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $68,884, of which $689 was distributed
to the managing general partner and $68,195 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.


                           Part II. Other Information

Item 6.        Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.


                                        9

   455


                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                             PARKER & PARSLEY 85-A, LTD.

                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 10, 2001               By:      /s/ Rich Dealy
                                            ---------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       10



   456
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 2-99079A


                           PARKER & PARSLEY 85-A, LTD.
             (Exact name of Registrant as specified in its charter)



                    TEXAS                                                       75-2064518
         ------------------------------                                 -----------------------
                                                                    
        (State or other jurisdiction of                                    (I.R.S. Employer
        incorporation or organization)                                  Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                75039
----------------------------------------------------------------              ---------
         (Address of principal executive offices)                             (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
           Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$9,426,000.

   As of March 8, 2001, the number of outstanding limited partnership interests
was 9,613.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None


PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   457




                                     PART I

ITEM 1.        BUSINESS

Parker & Parsley 85-A, Ltd. (the "Partnership") is a limited partnership
organized in 1985 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 9,613 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000, approximately 57% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial liability due to pollution and other
environmental damages. Although the Partnership believes that its business
operations do not impair environmental quality and that its costs of complying
with any



                                       2
   458



applicable environmental regulations are not currently significant, the
Partnership cannot predict what, if any, effect these environmental regulations
may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.      PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 25
productive oil and gas wells. At December 31, 2000, 21 wells were producing with
four wells sold during 1996.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.      LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.        SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter 2000.


                                       3
   459



                                     PART II

ITEM 5.        MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                 DISTRIBUTIONS

At March 8, 2001, the Partnership had 9,613 outstanding limited partnership
interests held of record by 820 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $372,121 and
$161,988 respectively, were made to the limited partners.

ITEM 6.        SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                                   2000       1999          1998         1 997            1996
                                               ----------   ----------   ----------   -----------   ------------
Operating results:
------------
                                                                                     
  Oil and gas sales                            $  757,929   $  526,325   $  371,098   $   548,786   $    631,838
                                               ==========   ==========   ==========   ===========   ============

  Impairment of oil and
    gas properties                             $       --   $       --   $   22,031   $   270,187   $         --
                                               ==========   ==========   ==========   ===========   ============

  Gain on litigation
    settlement, net                            $       --   $       --   $       --   $        --   $     32,694
                                               ==========   ==========   ==========   ===========   ============

  Net income (loss)                            $  379,203   $  178,927   $ (274,769)  $  (158,804)  $    221,854
                                               ==========   ==========   ==========   ===========   ============

  Allocation of net income
    (loss):
    Managing general partner                   $    3,792   $    1,789   $   (2,747)  $    (1,588)  $      2,219
                                               ==========   ==========   ==========   ===========   ============

      Limited partners                         $  375,411   $  177,138   $ (272,022)  $  (157,216)  $    219,635
                                               ==========   ==========   ==========   ===========   ============

  Limited partners' net
    income (loss) per limited
    partnership interest                       $    39.05   $   18.43    $   (28.30)  $    (16.35)  $      22.85
                                               ==========   ==========   ==========   ===========   ============


  Limited partners' cash
    distributions per limited
    partnership interest                       $    38.71   $    16.85   $     9.62   $     25.26   $      26.55 (a)
                                               ==========   ==========   ==========   ===========   ============

At year end:
------------
  Identifiable assets                          $  703,647   $  702,600   $  684,133   $ 1,059,494   $  1,460,408
                                               ==========   ==========   ==========   ===========   ============
-----------------------


(a) Including litigation settlement per limited partnership interest of $3.37 in
      1996.



                                       4
   460



ITEM 7.        MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                 RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 44% to $757,929 for 2000 as
compared to $526,325 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production from 1999 to 2000. In
2000, 16,975 barrels of oil, 10,483 barrels of natural gas liquids ("NGLs") and
41,549 mcf of gas were sold, or 34,383 barrel of oil equivalents ("BOEs"). In
1999, 17,451 barrels of oil, 13,795 barrels of NGLs and 55,226 mcf of gas were
sold, or 40,450 BOEs. Due to the decline characteristics of the Partnership's
oil and gas properties, management expects a certain amount of decline in
production in the future until the Partnership's economically recoverable
reserves are fully depleted.

The average price received per barrel of oil increased $12.27, or 72%, from
$17.11 in 1999 to $29.38 in 2000. The average price received per barrel of NGLs
increased $4.49, or 46%, from $9.71 in 1999 to $14.20 in 2000. The average price
received per mcf of gas increased 56% from $1.70 in 1999 to $2.66 in 2000. The
market price received for oil and gas has been extremely volatile in the past
decade and management expects a certain amount of volatility in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $386,863 as compared to $350,830
in 1999, an increase of $36,033, or 10%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $331,978 in 2000 and $284,086 in 1999, resulting in an
increase of $47,892, or 17%. The increase was primarily due to additional well
maintenance costs incurred to stimulate well production and higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
44% from $15,790 in 1999 to $22,738 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $19,018 in 2000 and $9,794 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $32,147 in 2000 as compared to $50,954 in 1999, representing a
decrease of $18,807, or 37%. This decrease was primarily due to a 17,541 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

                                       5
   461

The Partnership's 1999 oil and gas revenues increased 42% to $526,325 from
$371,098 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production from 1998 to 1999. In 1999, 17,451
barrels of oil, 13,795 barrels of NGLs and 55,226 mcf of gas were sold, or
40,450 BOEs. In 1998, 18,178 barrels of oil, 9,630 barrels of NGLs and 43,021
mcf of gas were sold, or 34,978 BOEs.

The average price received per barrel of oil increased $3.84, or 29%, from
$13.27 in 1998 to $17.11 in 1999. The average price received per barrel of NGLs
increased $3.20, or 49%, from $6.51 in 1998 to $9.71 in 1999. The average price
received per mcf of gas increased 9% from $1.56 in 1998 to $1.70 in 1999.

Total costs and expenses decreased in 1999 to $350,830 as compared to $649,476
in 1998, a decrease of $298,646, or 46%. The decrease was primarily due to
declines in depletion, the impairment of oil and gas properties and production
costs, offset by an increase in G&A.

Production costs were $284,086 in 1999 and $304,333 in 1998, resulting in a
decrease of $20,247, or 7%. The decrease was the combination of declines in well
maintenance costs and ad valorem taxes, offset by an increase in production
taxes due to an increase in oil and gas revenues.

During this period, G&A increased 42% from $11,133 in 1998 to $15,790 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $9,794 in
1999 and $8,231 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $22,031 related to its oil and gas properties during 1998.

Depletion was $50,954 in 1999 compared to $311,979 in 1998. This represented a
decrease of $261,025, or 84%. This decrease was primarily due to an increase in
proved reserves of 182,664 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas



                                       6
   462

prices. Although the favorable commodity price environment and stable field
service cost environment is expected to continue during 2001, there is no
assurance that commodity prices will not return to a less favorable level or
that field service costs will not escalate in the future, both of which could
negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $172,932 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $234,104, offset by increases in production costs paid
of $47,892, G&A expenses paid of $6,948 and working capital of $6,332. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $331,444 to oil and gas receipts,
offset by $97,340 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for equipment upgrades on various oil and gas properties.

Proceeds from asset dispositions of $2,454 and $279 were recognized in 2000 and
1999, respectively. Proceeds during 2000 of $2,205 were from salvage income
received on one fully depleted well and $249 from equipment credits received on
an active property. Proceeds during 1999 of $279 were from equipment credits
received on active properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $375,880, of which $3,759 was
distributed to the managing general partner and $372,121 to the limited
partners. In 1999, cash distributions to the partners were $163,624, of which
$1,636 was distributed to the managing general partner and $161,988 to the
limited partners.




                                       7
   463

              ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS


                                                                                         Page
                                                                                      
Financial Statements of Parker & Parsley 85-A, Ltd:
 Independent Auditors' Report.........................................................     9
 Balance Sheets as of December 31, 2000 and 1999......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14



                                       8
   464





                          INDEPENDENT AUDITORS' REPORT




The Partners
Parker & Parsley 85-A, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 85-A, Ltd. as of December
31, 2000 and 1999, and the related statements of income, partners' capital and
cash flows for each of the three years in the period ended December 31, 2000.
These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 85-A, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001






                                       9
   465



                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                    2000             1999
                                                 -----------    -----------
              ASSETS
              ------
                                                           
Current assets:
  Cash                                           $    72,868    $    73,810
  Accounts receivable - oil and gas sales            103,810         72,517
                                                 -----------    -----------

       Total current assets                          176,678        146,327
                                                 -----------    -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method             7,398,954      7,396,111
Accumulated depletion                             (6,871,985)    (6,839,838)
                                                 -----------    -----------

       Net oil and gas properties                    526,969        556,273
                                                 -----------    -----------

                                                 $   703,647    $   702,600
                                                 ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $    11,211    $    13,487

Partners' capital:
  Managing general partner                             6,936          6,903
  Limited  partners (9,613 interests)                685,500        682,210
                                                 -----------    -----------

                                                     692,436        689,113

                                                 $   703,647    $   702,600
                                                 ===========    ===========

















   The accompanying notes are an integral part of these financial statements.



                                       10
   466



                                 PARKER & PARSLEY 85-A, LTD.
                                (A Texas Limited Partnership)

                                   STATEMENTS OF OPERATIONS
                               For the years ended December 31





                                                      2000          1999           1998
                                                   ---------     ---------      ---------
                                                                       
Revenues:
  Oil and gas                                      $ 757,929     $ 526,325      $ 371,098
  Interest                                             5,932         3,432          3,609
  Gain on disposition of assets                        2,205           -              -
                                                     -------       -------        -------

                                                     766,066       529,757        374,707
                                                     -------       -------        -------

Costs and expenses:
  Oil and gas production                             331,978       284,086        304,333
  General and administrative                          22,738        15,790         11,133
  Impairment of oil and gas properties                   -             -           22,031
  Depletion                                           32,147        50,954        311,979
                                                     -------       -------        -------

                                                     386,863       350,830        649,476
                                                     -------       -------        -------

Net income (loss)                                  $ 379,203     $ 178,927      $(274,769)
                                                    ========      ========       ========

Allocation of net income (loss):
  Managing general partner                         $   3,792     $   1,789      $  (2,747)
                                                    ========      ========       ========

  Limited partners                                 $ 375,411     $ 177,138      $(272,022)
                                                    ========      ========       ========

Net income (loss) per limited partnership interest $   39.05     $   18.43      $  (28.30)
                                                    ========      ========       ========



















   The accompanying notes are an integral part of these financial statements.



                                       11
   467



                                 PARKER & PARSLEY 85-A, LTD.
                                (A Texas Limited Partnership)

                               STATEMENTS OF PARTNERS' CAPITAL






                                                     Managing
                                                      general       Limited
                                                      partner       partners        Total
                                                  -------------- -------------- -------------


                                                                     
Partners' capital at January 1, 1998              $  10,430      $1,031,517     $1,041,947

  Distributions                                        (933)        (92,435)      (93,368)

  Net loss                                           (2,747)       (272,022)      (274,769)
                                                    -------        --------       --------

Partners' capital at December 31, 1998                6,750         667,060       673,810

  Distributions                                      (1,636)       (161,988)     (163,624)

  Net income                                          1,789         177,138       178,927
                                                    -------        --------       -------

Partners' capital at December 31, 1999                6,903         682,210       689,113

  Distributions                                      (3,759)       (372,121)     (375,880)

  Net income                                          3,792         375,411       379,203
                                                    -------        --------       -------

Partners' capital at December 31, 2000            $   6,936      $  685,500     $ 692,436
                                                   ========       =========      ========






















   The accompanying notes are an integral part of these financial statements.



                                       12
   468


                           PARKER & PARSLEY 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                     2000          1999         1998
                                                   ---------    ---------    ---------
                                                                    
Cash flows from operating activities:
  Net income (loss)                                $ 379,203    $ 178,927    $(274,769)
  Adjustments to reconcile net income (loss)
   to net cash provided by operating activities:
     Impairment of oil and gas properties                 --           --       22,031
     Depletion                                        32,147       50,954      311,979
     Gain on disposition of assets                    (2,205)          --           --
  Changes in assets and liabilities:
     Accounts receivable                             (31,293)     (30,401)      24,699
     Accounts payable                                 (2,276)       3,164       (7,224)
                                                   ---------    ---------    ---------

       Net cash provided by operating activities     375,576      202,644       76,716
                                                   ---------    ---------    ---------

Cash flows from investing activities:
  Additions to oil and gas properties                 (3,092)      (6,987)     (12,611)
  Proceeds from asset dispositions                     2,454          279          323
                                                   ---------    ---------    ---------

       Net cash used in investing activities            (638)      (6,708)     (12,288)
                                                   ---------    ---------    ---------

Cash flows used in financing activities:
  Cash distributions to partners                    (375,880)    (163,624)     (93,368)
                                                   ---------    ---------    ---------

Net increase (decrease) in cash                         (942)      32,312      (28,940)
Cash at beginning of year                             73,810       41,498       70,438
                                                   ---------    ---------    ---------

Cash at end of year                                $  72,868    $  73,810    $  41,498
                                                   =========    =========    =========


















   The accompanying notes are an integral part of these financial statements.


                                       13
   469

                                 PARKER & PARSLEY 85-A, LTD.
                                (A Texas Limited Partnership)

                                NOTES TO FINANCIAL STATEMENTS
                               December 31, 2000, 1999 and 1998

NOTE 1.        ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 85-A, Ltd. (the "Partnership") is a limited partnership
organized in 1985 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.        SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       14
   470

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated, in part, to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.        IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $22,031 related to its
proved oil and gas properties during 1998.

NOTE 4.        INCOME TAXES



                                       15
   471

        The financial statement basis of the Partnership's net assets and
liabilities was $500,887 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                            2000          1999           1998
                                                         ---------     ---------      ---------

                                                                             
   Net income (loss) per statements of operations        $ 379,203     $ 178,927      $(274,769)
   Depletion and depreciation provisions for tax
     reporting purposes less than amounts for
     financial reporting purposes                           26,488        45,239        307,564
   Impairment of oil and gas properties for financial
     reporting purposes                                        -             -           22,031
   Other, net                                                 (713)         (817)         1,515
                                                           -------       -------        -------

         Net income per Federal income tax
           returns                                       $ 404,978     $ 223,349      $  56,341
                                                          ========      ========       ========


NOTE 5.        OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                   ---------     ---------      ----------
                                                                       
    Development costs                              $   3,092     $   6,987      $  12,611
                                                    ========      ========       ========



    Capitalized oil and gas properties consist of the following:



                                      2000              1999
                                    -----------    -----------
                                             
Proved properties:
  Property acquisition costs        $   488,509    $   488,509
  Completed wells and equipment       6,910,445      6,907,602
                                    -----------    -----------

                                      7,398,954      7,396,111
Accumulated depletion                (6,871,985)    (6,839,838)
                                    -----------    -----------

       Net oil and gas properties   $   526,969    $   556,273
                                    ===========    ===========







                                       16
   472


NOTE 6.        RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999           1998
                                                   ---------     ---------      ---------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 157,269     $ 148,638      $ 144,020

    Reimbursement of general and administrative
      expenses                                     $  19,018     $   9,794      $   8,231


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA and the Partnership are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                Pioneer USA (1)    Partnership
                                                               ----------------   -------------

                                                                          
    Revenues:
      Proceeds from disposition of depreciable properties          9.09091%        90.90909%
      All other revenues                                         24.242425%       75.757575%
    Costs and expenses:
      Lease acquisition costs, drilling and completion costs       9.09091%        90.90909%
      Operating costs, direct costs and general and
        administrative expenses                                  24.242425%       75.757575%

    (1)  Excludes Pioneer USA's 1% general partner ownership which is allocated
         at the Partnership level and 187 limited partner interests owned by
         Pioneer USA.

NOTE 7.        OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.













                                       17
   473




                                                              Oil and NGLs          Gas
                                                                 (bbls)            (mcf)
                                                             ------------       ----------

                                                                         
  Net proved reserves at January 1, 1998                          318,665          423,423
  Revisions                                                      (154,837)        (135,041)
  Production                                                      (27,808)         (43,021)
                                                              -----------       ----------

  Net proved reserves at December 31, 1998                        136,020          245,361
  Revisions                                                       304,597          520,701
  Production                                                      (31,246)         (55,226)
                                                              -----------       ----------

  Net proved reserves at December 31, 1999                        409,371          710,836
  Revisions                                                           430         (151,364)
  Production                                                      (27,458)         (41,549)
                                                              -----------       ----------

  Net proved reserves at December 31, 2000                        382,343          517,923
                                                              ===========       ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.51 per barrel of NGLs and $7.67 per mcf of gas,
discounted at 10% was approximately $2,812,000 and undiscounted was $5,248,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.


                                       18
   474




                                                              For the years ended December 31,
                                                             --------------------------------
                                                               2000        1999       1998
                                                             --------    --------    --------
                                                                     (in thousands)
                                                                            
Oil and gas producing activities:
  Future cash inflows                                        $ 12,368    $ 10,131    $  1,487
  Future production costs                                      (7,120)     (6,033)     (1,155)
                                                             --------    --------    --------

                                                                5,248       4,098         332
  10% annual discount factor                                   (2,436)     (1,879)       (102)
                                                             --------    --------    --------

  Standardized measure of discounted future net cash flows   $  2,812    $  2,219    $    230
                                                             ========    ========    ========





                                                          For the years ended December 31,
                                                         ------------------------------------
                                                           2000         1999          1998
                                                         --------     ---------     --------
                                                                  (in, thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (426)  $      (242)  $      (67)
    Net changes in prices and production costs              1,007           705         (709)
    Revisions of previous quantity estimates                 (150)        2,101         (195)
    Accretion of discount                                     222            22          114
    Changes in production rates, timing and other             (60)         (597)         (52)
                                                         --------     ---------     --------

    Change in present value of future net revenues            593         1,989         (909)
                                                         --------     ---------     --------

    Balance, beginning of year                              2,219           230        1,139
                                                         --------     ---------     --------

    Balance, end of year                               $    2,812   $     2,219   $      230
                                                        =========    ==========    =========


NOTE 8.        MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
            Plains Marketing, L.P.                    57%           49%             -
            NGTS LLC                                   9%           10%             3%
            Genesis Crude Oil, L.P.                    -             -             60%
            Western Gas Resources, Inc.                3%            7%            19%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $36,131, which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.        PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:




        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Partnership affairs. As managing
        general partner and operator of the Partnership's properties, all
        production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and



                                       19
   475

        general and administrative expenses. In return, it is allocated 1% of
        the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $9,613,000. Pioneer USA is required to contribute amounts equal to 1% of
        initial Partnership capital less commission and offering expenses
        allocated to the limited partners and to contribute amounts necessary to
        pay costs and expenses allocated to it under the partnership agreement
        to the extent its share of revenues does not cover such costs.

ITEM 9.      CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
               AND FINANCIAL DISCLOSURE

None.



                                       20
   476


                                    PART III

ITEM 10.       DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.




        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts


                                       21
   477

Institute of Technology in 1979 and received his M.B.A. in 1981 from the
University of Chicago. He became Executive Vice President - Business Development
of Pioneer and Pioneer USA in August 1997 and was also appointed a director of
Pioneer USA in August 1997. Mr. Dove assumed the position of Chief Financial
Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr. Dove joined
Parker & Parsley in May 1994 as Vice President - International and was promoted
to Senior Vice President - Business Development in October 1996, in which
position he served until August 1997. Prior to joining Parker & Parsley, Mr.
Dove was employed with Diamond Shamrock Corp., and its successor, Maxus Energy
Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   478


ITEM 11.       EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.       SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 187 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.


                                       23
   479


ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                                      2000          1999           1998
                                                   ---------     ----------     ---------
                                                                       
   Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 157,269     $ 148,638      $144,020

   Reimbursement of general and administrative
      expenses                                     $  19,018     $   9,794      $  8,231


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Partnership.



                                       24
   480



                                     PART IV

ITEM 14.       EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                Statements of partners' capital for the years ended December 31,
                   2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   481



                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 85-A, LTD.

Dated: March 27, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                --------------------------------
                                                Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                       
/s/ Scott D. Sheffield              President of Pioneer USA                  March 27, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 27, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 27, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 27, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 27, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 27, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       26
   482



                           PARKER & PARSLEY 85-A, LTD.

                                INDEX TO EXHIBITS


        The following documents are incorporated by reference in response to
Item 14(c):



Exhibit No.                             Description                       Page
----------                              -----------                       ----
                                                                    
       3(a)               Amended and Restated Certificate of                -
                          Limited Partnership of Parker & Parsley
                          85-A, Ltd. incorporated by reference to
                          Exhibit A of the Partnership's Registration
                          Statement on Form S-1 (Registration No.
                          2-99079) (hereinafter called the Partnership's
                          Registration Statement)

       4(b)               Agreement of Limited Partnership of                -
                          Parker & Parsley 85-A, Ltd. incorporated
                          by reference to an Exhibit of the Partnership's
                          Registration Statement

       4(c)               Form of Subscription Agreement and Power           -
                          of Attorney incorporated by reference to
                          an Exhibit of the Partnership's Registration
                          Statement

       4(d)               Specimen Certificate of Limited Partnership        -
                          Interest incorporated by reference to an
                          Exhibit of the Partnership's Registration
                          Statement





                                       27




   483





                           PARKER & PARSLEY 85-A, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  178,428   $  757,929   $  526,325   $  371,098   $  548,786   $  631,838
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   22,031   $  270,187   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $     --   $       --   $       --   $       --   $       --   $       --   $   32,694
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   73,567   $  379,203   $  178,927   $ (274,769)  $ (158,804)  $  221,854
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
        partner                    $          $      736   $    3,792   $    1,789   $   (2,747)  $   (1,588)  $    2,219
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $   72,831   $  375,411   $  177,138   $ (272,022)  $ (157,216)  $  219,635
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     7.58   $    39.05   $    18.43   $   (28.30)  $   (16.35)  $    22.85
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $     7.09   $    38.71   $    16.85   $     9.62   $    25.26   $    26.55(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $  708,666   $  703,647   $  702,600   $  684,133   $1,059,494   $1,460,408
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $3.37
     in 1996.



   484
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 85-B, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
85-B, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 85-B, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-

   485
                           PARKER & PARSLEY 85-B LTD.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $   7,988

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   7,627

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   1,155
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  145.70

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.08 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $  113.89

          --  as of December 31, 2000 (c)                                                     $  117.13

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  134.58

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  141.49

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     210
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2035, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-

   486

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 2-99079B


                           PARKER & PARSLEY 85-B, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                                 75-2075492
          ---------------------------------            ---------------------
           (State or other jurisdiction of                (I.R.S. Employer
           incorporation or organization)              Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas       75039
----------------------------------------------------------------     ---------
            (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]



   487

                           PARKER & PARSLEY 85-B, LTD.

                                TABLE OF CONTENTS




                                                                            Page
                                                                      
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000......................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000...........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001....................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000...........................    6

            Notes to Financial Statements.............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K..........................    9

            Signatures................................................   10





                                        2
   488

                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                    March 31,     December 31,
                                                      2001           2000
                                                   -----------    -----------
                                                   (Unaudited)
                       ASSETS

                                                            
Current assets:
  Cash                                             $    60,380    $    80,718
  Accounts receivable - oil and gas sales               95,223         84,740
                                                   -----------    -----------
           Total current assets                        155,603        165,458
                                                   -----------    -----------
Oil and gas properties - at cost, based on the
  on the successful efforts accounting method        5,317,256      5,317,256
Accumulated depletion                               (4,541,387)    (4,526,767)
                                                   -----------    -----------
           Net oil and gas properties                  775,869        790,489
                                                   -----------    -----------
                                                   $   931,472    $   955,947
                                                   ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $    12,172    $    10,515

Partners' capital:
  Managing general partner                               9,544          9,805
  Limited partners (7,988 interests)                   909,756        935,627
                                                   -----------    -----------
                                                       919,300        945,432
                                                   -----------    -----------
                                                   $   931,472    $   955,947
                                                   ===========    ===========


  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   489

                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                          Three months ended
                                                               March 31,
                                                      -------------------------
                                                          2001          2000
                                                      ----------     ----------

                                                               
Revenues:
  Oil and gas                                         $  179,094     $  135,322
  Interest                                                 1,282            987
                                                      ----------     ----------
                                                         180,376        136,309
                                                      ----------     ----------
Costs and expenses:
  Oil and gas production                                  61,176         57,367
  General and administrative                               5,373          4,060
  Depletion                                               14,620         13,863
                                                      ----------     ----------
                                                          81,169         75,290
                                                      ----------     ----------
Net income                                            $   99,207     $   61,019
                                                      ==========     ==========
Allocation of net income:
  Managing general partner                            $      992     $      610
                                                      ==========     ==========
  Limited partners                                    $   98,215     $   60,409
                                                      ==========     ==========
Net income per limited partnership interest           $    12.30     $     7.56
                                                      ==========     ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        4
   490

                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                        Managing
                                        general       Limited
                                        partner       partners        Total
                                       ---------     ----------     ----------

                                                           
Balance at January 1, 2001             $   9,805     $  935,627     $  945,432

  Distributions                           (1,253)      (124,086)      (125,339)

  Net income                                 992         98,215         99,207
                                       ---------     ----------     ----------

Balance at March 31, 2001              $   9,544     $  909,756     $  919,300
                                       =========     ==========     ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements



                                        5
   491

                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                        Three months ended
                                                            March 31,
                                                     -------------------------
                                                        2001           2000
                                                     ----------     ----------
                                                              
Cash flows from operating activities:
   Net income                                        $   99,207     $   61,019
   Adjustments to reconcile net income to net
     cash provided by operating activities:
        Depletion                                        14,620         13,863
   Changes in assets and liabilities:
     Accounts receivable                                (10,483)        (3,406)
     Accounts payable                                     1,657          1,184
                                                     ----------     ----------
         Net cash provided by operating activities      105,001         72,660
                                                     ----------     ----------
Cash flows used in investing activities:
   Additions to oil and gas properties                       --         (1,898)
Cash flows used in financing activities:
   Cash distributions to partners                      (125,339)       (64,107)
                                                     ----------     ----------
Net increase (decrease) in cash                         (20,338)         6,655
Cash at beginning of period                              80,718         74,959
                                                     ----------     ----------
Cash at end of period                                $   60,380     $   81,614
                                                     ==========     ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        6
   492

                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 85-B, Ltd. (the "Partnership") is a limited partnership
organized in 1985 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 32% to $179,094 for the three
months ended March 31, 2001 as compared to $135,322 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 3,660 barrels
of oil, 1,334 barrels of natural gas liquids ("NGLs") and 8,365 mcf of gas were
sold, or 6,388 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 3,488 barrels of oil, 1,505 barrels of NGLs and 7,429 mcf of gas
were sold, or 6,231 BOEs.



                                       7
   493

The average price received per barrel of oil increased slightly from $28.65 for
the three months ended March 31, 2000 to $28.85 for the same period in 2001. The
average price received per barrel of NGLs increased $4.53, or 31%, from $14.41
for the three months ended March 31, 2000 to $18.94 for the same period in 2001.
The average price received per mcf of gas increased 214% from $1.84 during the
three months ended March 31, 2000 to $5.77 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $81,169 for the three months ended March
31, 2001 as compared to $75,290 for the same period in 2000, an increase of
$5,879, or 8%. This increase was primarily due to increases in production costs,
general and administrative expenses ("G&A") and depletion.

Production costs were $61,176 for the three months ended March 31, 2001 and
$57,367 for the same period in 2000, an increase of $3,809, or 7%. The increase
was primarily due to higher production taxes associated with higher oil and gas
prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 32% from $4,060 for the three months ended March 31, 2000 to $5,373
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $14,620 for the three months ended March 31, 2001 as compared to
$13,863 for the same period in 2000, an increase of $757, or 5%. The increase
was primarily due to an increase in oil production of 172 barrels for the period
ended March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $32,341 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to an increase of $44,067 in oil and gas sales receipts, offset by increases in
production costs of $3,809, G&A expenses of $1,313 and working capital of
$6,604. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2001 which contributed an additional $36,947 to oil and
gas receipts and $7,120 resulting from the increase in production during 2001.
The increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to an increase in the accrual for tax preparation fees.




                                       8
   494

Net Cash Used in Investing Activities

The Partnership's investing activities for the three months ended March 31, 2000
were related to equipment upgrades on active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $125,339, of which $1,253 was distributed to the managing general partner
and $124,086 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $64,107, of which $641 was distributed
to the managing general partner and $63,466 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.

                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.




                                       9
   495

                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                             PARKER & PARSLEY 85-B, LTD.


                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 10, 2001                By:     /s/ Rich Dealy
                                            ------------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer



                                       10

   496
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 2-99079B


                           PARKER & PARSLEY 85-B, LTD.
             (Exact name of Registrant as specified in its charter)

             TEXAS                                    75-2075492
-------------------------------                  ---------------------
(State or other jurisdiction of                     (I.R.S. Employer
incorporation or organization)                   Identification Number)



                                                                              
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                      75039
----------------------------------------------------------------                  -------------
         (Address of principal executive offices)                                   (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
           Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$7,930,000.

            As of March 8, 2001, the number of outstanding limited partnership
interests was 7,988.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None


PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.
   497



                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 85-B, Ltd. (the "Partnership") is a limited partnership
organized in 1985 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 7,988 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000, approximately 48%, 20% and 10% were attributable to sales
made to Mobil Oil Corporation, Plains Marketing, L.P. and NGTS LLC,
respectively. Pioneer USA is of the opinion that the loss of any one purchaser
would not have an adverse effect on its ability to sell its oil, natural gas
liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations. The oil and gas business is
also subject to environmental hazards such as oil spills, gas leaks and ruptures
and discharges of toxic substances or gases that could expose the Partnership to
substantial


                                       2
   498



liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.      PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 22
productive oil and gas wells. One well was converted to a saltwater disposal
well during 1987 and four wells have been plugged and abandoned. At December 31,
2000, the Partnership had 17 producing wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.      LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.      SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.




                                       3
   499


                                     PART II

ITEM 5.      MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
             DISTRIBUTIONS

At March 8, 2001, the Partnership had 7,988 outstanding limited partnership
interests held of record by 717 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $309,279 and
$115,631, respectively, were made to the limited partners.

ITEM 6.      SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                 2000         1999         1998          1997         1996
                              ---------     --------     ---------     --------     ---------
                                                                    
Operating results:
-----------------
  Oil and gas sales          $  619,365    $ 387,551    $  341,048    $ 538,813    $  616,863
                              =========     ========     =========     ========     =========

  Impairment of oil and
    gas properties           $   10,050    $  95,253    $   52,922    $ 324,374    $      -
                              =========     ========     =========     ========     =========

  Gain on litigation
    settlement, net          $      -      $     -      $      -      $     -      $   62,948
                              =========     ========     =========     ========     =========

  Net income (loss)          $  277,323    $ (14,097)   $ (117,257)   $(177,091)   $  286,574
                              =========     ========     =========     ========     =========

  Allocation of net income
    (loss):
      Managing general
        partner              $    2,773    $    (141)   $   (1,172)   $  (1,771)   $    2,866
                              =========     ========     =========     ========     =========

      Limited partners       $  274,550    $ (13,956)   $ (116,085)   $(175,320)   $  283,708
                              =========     ========     =========     ========     =========

  Limited partners' net
    income (loss) per limited
    partnership interest     $    34.37    $   (1.75)    $  (14.53)   $  (21.95)   $    35.52
                              =========     ========      ========     ========     =========

  Limited partners' cash
    distributions per limited
    partnership interest     $    38.72    $   14.48     $   17.29    $   33.72    $    42.90 (a)
                              =========    =========      ========     ========     =========

At year end:
-----------
  Identifiable assets        $  955,947    $ 992,521    $1,122,069    $1,386,758   $1,831,497
                              =========     ========     =========     =========    =========

--------------

(a)     Including litigation settlement per limited partnership interest of
        $7.80 in 1996.





                                       4
   500


ITEM 7.       MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
              RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 60% to $619,365 for 2000 as
compared to $387,551 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 14,002
barrels of oil, 6,807 barrels of natural gas liquids ("NGLs") and 30,909 mcf of
gas were sold, or 25,961 barrel of oil equivalents ("BOEs"). In 1999, 14,280
barrels of oil, 7,130 barrels of NGLs and 33,467 mcf of gas were sold, or 26,988
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $11.95, or 66%, from
$18.07 in 1999 to $30.02 in 2000. The average price received per barrel of NGLs
increased $5.86, or 58%, from $10.10 in 1999 to $15.96 in 2000. The average
price received per mcf of gas increased 70% from $1.72 in 1999 to $2.92 in 2000.
The market price for oil and gas has been extremely volatile in the past decade
and management expects a certain amount of volatility in the foreseeable future.
The Partnership may therefore sell its future oil and gas production at average
prices lower or higher than that received in 2000.

Total costs and expenses decreased in 2000 to $347,682 as compared to $404,907
in 1999, a decrease of $57,225, or 14%. The decrease was primarily due to
declines in the impairment of oil and gas properties and depletion, offset by
increases in production costs and general and administrative expenses ("G&A").

Production costs were $264,543 in 2000 and $207,744 in 1999, resulting in an
increase of $56,799, or 27%. The increase was primarily due to additional well
maintenance costs incurred to stimulate well production and higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
60% from $11,626 in 1999 to $18,581 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $15,555 in 2000 and $6,624 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized
non-cash charges of $10,050 and $95,253 related to its oil and gas properties
during 2000 and 1999, respectively.



                                       5
   501

Depletion was $54,508 in 2000 as compared to $90,284 in 1999, representing a
decrease of $35,776, or 40%. This decrease was primarily due to a 17,204 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices and a reduction in the Partnership's net depletable basis from charges
taken in accordance with SFAS 121 during the fourth quarter of 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 14% to $387,551 from
$341,048 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 14,280 barrels of oil,
7,130 barrels of NGLs and 33,467 mcf of gas were sold, or 26,988 BOEs. In 1998,
16,204 barrels of oil, 8,599 barrels of NGLs and 41,501 mcf of gas were sold, or
31,720 BOEs.

The average price received per barrel of oil increased $4.77, or 36%, from
$13.30 in 1998 to $18.07 in 1999. The average price received per barrel of NGLs
increased $3.15, or 45%, from $6.95 in 1998 to $10.10 in 1999. The average price
received per mcf of gas increased 9% from $1.58 in 1998 to $1.72 in 1999.

Total costs and expenses decreased in 1999 to $404,907 as compared to $462,704
in 1998, a decrease of $57,797, or 12%. The decrease was primarily due to
declines in production costs and depletion, offset by increases in the
impairment of oil and gas properties and G&A.

Production costs were $207,744 in 1999 and $269,093 in 1998, resulting in a
$61,349 decrease, or 23%. The decrease was attributable to less well maintenance
costs and ad valorem taxes.

During this period, G&A increased, in aggregate, 14% from $10,231 in 1998 to
$11,626 in 1999 primarily due to a higher percentage of the managing general
partner's G&A being allocated (limited to 3% of oil and gas revenues) as a
result of increased oil and gas revenues. The Partnership paid the managing
general partner $6,624 in 1999 and $7,884 in 1998 for G&A incurred on behalf of
the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $95,253 and $52,922
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion was $90,284 in 1999 compared to $130,458 in 1998. This represented a
decrease of $40,174, or 31%. This decrease was the result of an increase in
proved reserves of 117,564 barrels of oil during 1999 as a result of higher
commodity prices, a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998 and
a decline in oil production of 1,924 barrels for the period ended December 31,
1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but



                                       6
   502

to a lesser extent, market prices for natural gas declined. During 1999 and
2000, the Organization of Petroleum Exporting Countries ("OPEC") and certain
other crude oil exporting nations announced reductions in their planned export
volumes. Those announcements, together with the enactment of the announced
reductions in export volumes, had a positive impact on world oil prices, as have
overall natural gas supply and demand fundamentals on North American natural gas
prices. Although the favorable commodity price environment and stable field
service cost environment is expected to continue during 2001, there is no
assurance that commodity prices will not return to a less favorable level or
that field service costs will not escalate in the future, both of which could
negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $163,858 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $234,195, offset by increases in production costs paid
of $56,799, G&A expenses paid of $6,955 and working capital of $6,583. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $255,175 to oil and gas receipts,
offset by a decrease of $20,980 resulting from the decline in production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices and well maintenance costs
incurred to stimulate well production. The increase in G&A was primarily due to
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were for
expenditures related to oil and gas equipment upgrades on active properties.

Proceeds from disposition of assets of $6,412 and $134 during 2000 and 1999,
respectively, were from equipment credits received on active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $312,403, of which $3,124 was
distributed to the managing general partner and $309,279 to the limited
partners. In 1999, cash distributions to the partners were $116,799, of which
$1,168 was distributed to the managing general partner and $115,631 to the
limited partners.



                                       7
   503

ITEM 8.       FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA



                          INDEX TO FINANCIAL STATEMENTS
                                                                                         Page
                                                                                         ----
                                                                                     
Financial Statements of Parker & Parsley 85-B, Ltd:
 Independent Auditors' Report.........................................................     9
 Balance Sheets as of December 31, 2000 and 1999......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14





                                       8
   504




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 85-B, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 85-B, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 85-B, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       9
   505


                          PARKER & PARSLEY 85-B, LTD.
                         (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                  December 31





                                                         2000           1999
                                                     -----------    -----------
                     ASSETS

Current assets:
                                                              
  Cash                                               $    80,718    $    74,959
  Accounts receivable - oil and gas sales                 84,740         59,750
                                                     -----------    -----------

        Total current assets                             165,458        134,709
                                                     -----------    -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                 5,317,256      5,320,021
Accumulated depletion                                 (4,526,767)    (4,462,209)
                                                     -----------    -----------

        Net oil and gas properties                       790,489        857,812
                                                     -----------    -----------

                                                     $   955,947    $   992,521
                                                     ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $    10,515    $    12,009

Partners' capital:
  Managing general partner                                 9,805         10,156
  Limited partners (7,988 interests)                     935,627        970,356
                                                     -----------    -----------

                                                         945,432        980,512
                                                     -----------    -----------

                                                     $   955,947    $   992,521
                                                     ===========    ===========




                                       10
   506
   The accompanying notes are an integral part of these financial statements.
                          PARKER & PARSLEY 85-B, LTD.
                         (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                        For the years ended December 31




                                               2000        1999         1998
                                            ---------   ---------    ---------

Revenues:
  Oil and gas                               $ 619,365   $ 387,551    $ 341,048
  Interest                                      5,640       3,259        4,399
                                            ---------   ---------    ---------

                                              625,005     390,810      345,447
                                            ---------   ---------    ---------

Costs and expenses:
  Oil and gas production                      264,543     207,744      269,093
  General and administrative                   18,581      11,626       10,231
  Impairment of oil and gas properties         10,050      95,253       52,922
  Depletion                                    54,508      90,284      130,458
                                            ---------   ---------    ---------

                                              347,682     404,907      462,704
                                            ---------   ---------    ---------

Net income (loss)                           $ 277,323   $ (14,097)   $(117,257)
                                            =========   =========    =========

Allocation of net income (loss):
  Managing general partner                  $   2,773   $    (141)   $  (1,172)
                                            =========   =========    =========

  Limited partners                          $ 274,550   $ (13,956)   $(116,085)
                                            =========   =========    =========

Net income (loss) per limited partnership
  interest                                  $   34.37   $  (1.75)  $    (14.53)
                                            =========   =========    =========




                                       11
   507

   The accompanying notes are an integral part of these financial statements.
                           PARKER & PARSLEY 85-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                    Managing
                                                    general       Limited
                                                    partner       partners        Total
                                                -------------- -------------- --------------
                                                                       
Partners' capital at January 1, 1998              $  14,031      $1,354,156     $1,368,187

  Distributions                                      (1,394)       (138,128)     (139,522)

  Net loss                                           (1,172)       (116,085)      (117,257)
                                                    -------        --------       --------

Partners' capital at December 31, 1998               11,465       1,099,943     1,111,408

  Distributions                                      (1,168)       (115,631)     (116,799)

  Net loss                                             (141)        (13,956)      (14,097)
                                                    -------        --------       -------

Partners' capital at December 31, 1999               10,156         970,356       980,512

  Distributions                                      (3,124)       (309,279)     (312,403)

  Net income                                          2,773         274,550       277,323
                                                    -------        --------       -------

Partners' capital at December 31, 2000            $   9,805      $  935,627     $ 945,432
                                                   ========       =========      ========



                                       12
   508

   The accompanying notes are an integral part of these financial statements.
                          PARKER & PARSLEY 85-B, LTD.
                         (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                        For the years ended December 31





                                                        2000         1999         1998
                                                     ---------    ---------    ---------

Cash flows from operating activities:
                                                                      
  Net income (loss)                                  $ 277,323    $ (14,097)   $(117,257)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties              10,050       95,253       52,922
      Depletion                                         54,508       90,284      130,458
  Changes in assets and liabilities:
      Accounts receivable                              (24,990)     (21,249)      46,814
      Accounts payable                                  (1,494)       1,348       (7,910)
                                                     ---------    ---------    ---------

         Net cash provided by operating activities     315,397      151,539      105,027
                                                     ---------    ---------    ---------

Cash flows from investing activities:
  Additions to oil and gas equipment                    (3,647)      (7,285)      (7,947)
  Proceeds from disposition of assets                    6,412          134           --
                                                     ---------    ---------    ---------

         Net cash provided by (used in)
             investing activities                        2,765       (7,151)      (7,947)
                                                     ---------    ---------    ---------

Cash flows used in financing activities:
  Cash distributions to partners                      (312,403)    (116,799)    (139,522)
                                                     ---------    ---------    ---------

Net increase (decrease) in cash                          5,759       27,589      (42,442)
Cash at beginning of year                               74,959       47,370       89,812
                                                     ---------    ---------    ---------

Cash at end of year                                  $  80,718    $  74,959    $  47,370
                                                     =========    =========    =========





                                       13
   509

   The accompanying notes are an integral part of these financial statements.
                          PARKER & PARSLEY 85-B, LTD.
                         (A Texas Limited Partnership)

                         NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

       Parker & Parsley 85-B, Ltd. (the "Partnership") is a limited partnership
organized in 1985 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

       The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

       A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

       Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

       Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

       Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

       Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

       Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

                                       14
   510

       Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

       General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

       Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

       Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

       Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.  IMPAIRMENT OF LONG-LIVED ASSETS

       In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $10,050, $95,253 and
$52,922 related to its proved oil and gas properties during 2000, 1999 and 1998,
respectively.

                                       15
   511

NOTE 4.  INCOME TAXES

       The financial statement basis of the Partnership's net assets and
liabilities was $89,078 greater than the tax basis at December 31, 2000.

       The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                 2000         1999         1998
                                                               ---------    ---------    ---------

                                                                                
   Net income (loss) per statements of operations              $ 277,323    $ (14,097)   $(117,257)
   Depletion and depreciation provisions for tax
     reporting purposes less than amounts for
     financial reporting purposes                                 50,022       86,267      127,807
   Impairment of oil and gas properties for financial
     reporting purposes                                           10,050       95,253       52,922
   Other, net                                                      5,557       (1,887)       2,207
                                                               ---------    ---------    ---------

        Net income per Federal income tax
          returns                                              $ 342,952    $ 165,536    $  65,679
                                                               =========    =========    =========


NOTE 5.  OIL AND GAS PRODUCING ACTIVITIES

       The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                     2000          1999           1998
                                                    ------        ------         ------

                                                                       
      Development costs                            $   3,647     $   7,285      $   7,947
                                                    ========      ========       ========



    Capitalized oil and gas properties consist of the following:



                                            2000           1999
                                        -----------    -----------
    Proved properties:
                                                 
      Property acquisition costs        $   292,864    $   292,864
      Completed wells and equipment       5,024,392      5,027,157
                                        -----------    -----------

                                          5,317,256      5,320,021
    Accumulated depletion                (4,526,767)    (4,462,209)
                                        -----------    -----------

           Net oil and gas properties   $   790,489    $   857,812
                                        ===========    ===========








                                       16
   512


NOTE 6.  RELATED PARTY TRANSACTIONS

       Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                     2000       1999       1998
                                                   --------   --------   ---------

                                                                 
      Payment of lease operating and supervision
        charges in accordance with standard
        industry operating agreements               $105,647   $ 97,004   $111,206

      Reimbursement of general and administrative
        expenses                                    $ 15,555   $  6,624   $  7,884


       The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA and the Partnership are parties to the Program agreement.

       The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                 Pioneer
                                                                 USA (1)         Partnership
                                                              -------------     -------------

                                                                          
    Revenues:
      Proceeds from disposition of depreciable properties      9.09091%         90.90909%
      All other revenues                                      24.242425%        75.757575%
    Costs and expenses:
      Lease acquisition costs, drilling and completion costs   9.09091%         90.90909%
      Operating costs, direct costs and general and
        administrative expenses                               24.242425%        75.757575%


    (1)  Excludes Pioneer USA's 1% general partner ownership which is allocated
         at the Partnership level and 58 limited partner interests owned by
         Pioneer USA.

NOTE 7.       OIL AND GAS INFORMATION (UNAUDITED)

       The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.







                                       17
   513




                                                               Oil and NGLs         Gas
                                                                  (bbls)            (mcf)
                                                               -------------     ------------
                                                                          
  Net proved reserves at January 1, 1998                          333,208           531,982
  Revisions                                                      (139,875)         (179,491)
  Production                                                      (24,803)          (41,501)
                                                                 --------          --------

  Net proved reserves at December 31, 1998                        168,530           310,990
  Revisions                                                       177,510           247,011
  Production                                                      (21,410)          (33,467)
                                                                 --------          --------

  Net proved reserves at December 31, 1999                        324,630           524,534
  Revisions                                                           634           (33,966)
  Production                                                      (20,809)          (30,909)
                                                                 --------          --------

  Net proved reserves at December 31, 2000                        304,455           459,659
                                                                 ========          ========


       As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.43 per barrel of NGLs and $7.87 per mcf of gas,
discounted at 10% was approximately $2,332,000 and undiscounted was $4,536,000.

       Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                       18
   514




                                                              For the years ended December 31,
                                                           -------------------------------------
                                                              2000         1999          1998
                                                           -----------   ---------    ----------
                                                                     (in thousands)
                                                                            
Oil and gas producing activities:
  Future cash inflows                                        $ 10,394    $  8,008    $  1,850
  Future production costs                                      (5,858)     (4,882)     (1,499)
                                                             --------    --------    --------

                                                                4,536       3,126         351
  10% annual discount factor                                   (2,204)     (1,410)        (95)
                                                             --------    --------    --------

  Standardized measure of discounted future net cash flows   $  2,332    $  1,716    $    256
                                                             ========    ========    ========




                                                             For the years ended December 31,
                                                       -------------------------------------------
                                                          2000            1999           1998
                                                         --------     ---------     --------
                                                                      (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (355)  $      (180)  $      (72)
    Net changes in prices and production costs              1,003           954         (923)
    Revisions of previous quantity estimates                  (33)        1,209         (154)
    Accretion of discount                                     172            25          133
    Changes in production rates, timing and other            (171)         (548)         (54)
                                                         --------     ---------     --------

    Change in present value of future net revenues            616         1,460       (1,070)
                                                         --------     ---------     --------

    Balance, beginning of year                              1,716           256        1,326
                                                         --------     ---------     --------

    Balance, end of year                               $    2,332   $     1,716   $      256
                                                        =========    ==========    =========


NOTE 8.  MAJOR CUSTOMERS

       The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:


                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                          
           Mobil Oil Corporation                      48%            51%           45%
           Plains Marketing, L.P.                     20%            16%            -
           NGTS LLC                                   10%             7%            1%
           Western Gas Resources, Inc.                 4%             6%           29%
           Genesis Crude Oil, L.P.                     -              -            18%


       At December 31, 2000, the amounts receivable from Mobil Oil Corporation,
Plains Marketing, L.P. and NGTS LLC were $23,621, $7,883 and $1,228,
respectively, which are included in the caption "Accounts receivable - oil and
gas sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.  PARTNERSHIP AGREEMENT

       The following is a brief summary of the more significant provisions of
the limited partnership agreement:

       Managing general partner - The managing general partner of the
       Partnership is Pioneer USA. Pioneer USA has the power and authority to
       manage, control and administer all Partnership affairs. As managing
       general partner and operator of the Partnership's properties, all
       production expenses are incurred by Pioneer USA and billed to the
       Partnership. The majority of the Partnership's oil and gas revenues are
       received directly by the Partnership, however, a portion of the oil and
       gas revenue is initially received by Pioneer USA prior to being paid to
       the Partnership. Under the limited partnership agreement, the managing
       general partner pays 1% of the Partnership's acquisition, drilling and
       completion costs and 1% of its operating and general and administrative
       expenses. In return, it is allocated 1% of the Partnership's revenues.



                                       19
   515

       Limited partner liability - The maximum amount of liability of any
       limited partner is the total contributions of such partner plus his share
       of any undistributed profits.

       Initial capital contributions - The limited partners entered into
       subscription agreements for aggregate capital contributions of
       $7,988,000. Pioneer USA is required to contribute amounts equal to 1% of
       initial Partnership capital less commission and offering expenses
       allocated to the limited partners and to contribute amounts necessary to
       pay costs and expenses allocated to it under the Partnership agreement to
       the extent its share of revenues does not cover such costs.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
         AND FINANCIAL DISCLOSURE

None.




                                       20
   516


                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


       Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   517


       Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

       Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

       Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

       Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.




                                       22
   518


ITEM 11. EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays 10% of the Program's acquisition, drilling and
completion costs and 25% of its operating and general and administrative
expenses. In return, Pioneer USA is allocated 25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)   Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 58 limited partner interests at January 1, 2001.

(b)   Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.



                                       23
   519

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:







                                                        2000          1999           1998
                                                   ------------- -------------  -------------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 105,647     $  97,004      $111,206

    Reimbursement of general and administrative
      expenses                                     $  15,555     $   6,624      $  7,884


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.




                                       24
   520


                                     PART IV


ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.    Financial statements

            The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                Statements of partners' capital for the years ended December 31,
                   2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                Notes to financial statements

      2.    Financial statement schedules

            All financial statement schedules have been omitted since the
            required information is in the financial statements or notes
            thereto, or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   521


                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                              PARKER & PARSLEY 85-B, LTD.

Dated: March 27, 2001         By:   Pioneer Natural Resources USA, Inc.
                                       Managing General Partner


                                    By:   /s/ Scott D. Sheffield
                                          ------------------------------------
                                          Scott D. Sheffield, President

       Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                       
/s/ Scott D. Sheffield              President of Pioneer USA                  March 27, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 27, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 27, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 27, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 27, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 27, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       26
   522


                           PARKER & PARSLEY 85-B, LTD.

                                INDEX TO EXHIBITS




       The following documents are incorporated by reference in response to Item
14(c):



     Exhibit No.                         Description                              Page
     -----------                         -----------                              ----

                                                                          
       3(a)               Amended and Restated Certificate of                       -
                          Limited Partnership of Parker & Parsley
                          85-B, Ltd. incorporated by reference to
                          Exhibit A of the Partnership's Registration
                          Statement on Form S-1 (Registration No.
                          2-99079) (hereinafter called the Partnership's
                          Registration Statement)

       4(a)               Agreement of Limited Partnership of                       -
                          Parker & Parsley 85-B, Ltd. incorporated by
                          reference to an Exhibit of the Partnership's
                          Registration Statement

       4(b)               Form of Subscription Agreement and Power                  -
                          of Attorney incorporated by reference to an
                          Exhibit of the Partnership's Registration
                          Statement

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to an Exhibit
                          of the Partnership's Registration Statement









                                       27
   523



                           PARKER & PARSLEY 85-B, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  135,322   $  619,365   $  387,551   $  341,048   $  538,813   $  616,863
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   10,050   $   95,253   $   52,922   $  324,374   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $     --   $       --   $       --   $       --   $       --   $       --   $   62,948
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   61,019   $  277,323   $  (14,097)  $ (117,257)  $ (177,091)  $  286,574
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
         Managing general
           partner                 $          $      610   $    2,773   $     (141)  $   (1,172)  $   (1,771)  $    2,866
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   60,409   $  274,550   $  (13,956)  $ (116,085)  $ (175,320)  $  283,708
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     7.56   $    34.37   $    (1.75)  $   (14.53)  $   (21.95)  $    35.52
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $     7.95   $    38.72   $    14.48   $    17.29   $    33.72   $    42.90(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $  990,617   $  955,947   $  992,521   $1,122,069   $1,386,758   $1,831,497
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $7.80
     in 1996.



   524
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

   PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Private Investment 85-A, Ltd. and supplements the proxy statement/prospectus
dated       , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Private Investment 85-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-

   525
                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.


                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $   5,000

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   5,658

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   1,433
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  293.69

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          4.20 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $  145.15

          --  as of December 31, 2000 (c)                                                     $  148.95

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  280.04

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  284.97

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     275
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2035, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   526



                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   527



                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS





                                                     March 31,     December 31,
                                                       2001            2000
                                                   ------------    ------------
                                                   (Unaudited)
                                                             
                    ASSETS
Current assets:
  Cash                                             $     76,097    $     74,084
  Accounts receivable - oil and gas sales                58,537          68,251
                                                   ------------    ------------
        Total current assets                            134,634         142,335
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                3,399,009       3,399,009
Accumulated depletion                                (2,788,623)     (2,780,814)
                                                   ------------    ------------
        Net oil and gas properties                      610,386         618,195
                                                   ------------    ------------
                                                   $    745,020    $    760,530
                                                   ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $      9,489    $      5,818

Partners' capital:
  Managing general partner                                9,765           9,957
  Limited partners (125 interests)                      725,766         744,755
                                                   ------------    ------------
                                                        735,531         754,712
                                                   ------------    ------------
                                                   $    745,020    $    760,530
                                                   ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2

   528


                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                      Three months ended
                                                           March 31,
                                                   -----------------------
                                                      2001         2000
                                                   ----------   ----------
                                                          
Revenues:
  Oil and gas                                      $  123,326   $  118,048
  Interest                                              1,135        1,076
  Gain on disposition of assets                            --       23,661
                                                   ----------   ----------
                                                      124,461      142,785
                                                   ----------   ----------
Costs and expenses:
  Oil and gas production                               38,813       38,872
  General and administrative                            2,467        2,361
  Depletion                                             7,809       10,857
  Abandoned property                                       --        6,855
                                                   ----------   ----------
                                                       49,089       58,945
                                                   ----------   ----------
Net income                                         $   75,372   $   83,840
                                                   ==========   ==========
Allocation of net income:
  Managing general partner                         $      754   $      838
                                                   ==========   ==========
  Limited partners                                 $   74,618   $   83,002
                                                   ==========   ==========
Net income per limited partnership interest        $   596.94   $   664.02
                                                   ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   529



                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                       Managing
                                        general      Limited
                                        partner      partners        Total
                                      ----------    ----------    ----------
                                                         
Balance at January 1, 2001            $    9,957    $  744,755    $  754,712

    Distributions                           (946)      (93,607)      (94,553)

    Net income                               754        74,618        75,372
                                      ----------    ----------    ----------

Balance at March 31, 2001             $    9,765    $  725,766    $  735,531
                                      ==========    ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   530



                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                          Three months ended
                                                              March 31,
                                                       ------------------------
                                                         2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $   75,372    $   83,840
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            7,809        10,857
       Gain on disposition of assets                           --       (23,661)
  Changes in assets and liabilities:
       Accounts receivable                                  9,714        (3,617)
       Accounts payable                                     3,671         6,538
                                                       ----------    ----------
         Net cash provided by operating activities         96,566        73,957
                                                       ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                          --           (21)
  Proceeds from disposition of assets                          --        23,867
                                                       ----------    ----------
         Net cash provided by investing activities             --        23,846
                                                       ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                          (94,553)      (78,309)
                                                       ----------    ----------
Net increase in cash                                        2,013        19,494
Cash at beginning of period                                74,084        79,497
                                                       ----------    ----------
Cash at end of period                                  $   76,097    $   98,991
                                                       ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.




                                        5
   531



                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley Private Investment 85-A, Ltd. (the "Partnership") is a limited
partnership organized in 1985 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 4% to $123,326 for the three
months ended March 31, 2001 as compared to $118,048 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 2,835
barrels of oil, 1,012 barrels of natural gas liquids ("NGLs") and 4,506 mcf of
gas were sold, or 4,598 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 3,392 barrels of oil, 1,300 barrels of NGLs and 5,061 mcf
of gas were sold, or 5,536 BOEs.


                                        6

   532



The average price received per barrel of oil increased $1.37, or 5%, from $27.36
for the three months ended March 31, 2000 to $28.73 for the same period in 2001.
The average price received per barrel of NGLs increased $3.99, or 30%, from
$13.27 for the three months ended March 31, 2000 to $17.26 for the same period
in 2001. The average price received per mcf of gas increased 243% from $1.58
during the three months ended March 31, 2000 to $5.42 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

A gain on disposition of assets of $23,661 was recognized during the three
months ended March 31, 2000 due to equipment credits received on two wells
plugged and abandoned during 2000. Abandoned property costs of $6,855 incurred
during the three months ended March 31, 2000 were related to the abandonment of
these two wells.

Costs and Expenses:

Total costs and expenses decreased to $49,089 for the three months ended March
31, 2001 as compared to $58,945 for the same period in 2000, a decrease of
$9,856, or 17%. This decrease was due to declines in abandoned property costs,
depletion and production costs, offset by an increase in general and
administrative expenses ("G&A").

Production costs were $38,813 for the three months ended March 31, 2001 and
$38,872 for the same period in 2000 resulting in a $59 decrease. The decrease
was due to lower well maintenance costs, offset by higher production taxes
associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 4% from $2,361 for the three months ended March 31, 2000 to $2,467 for
the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $7,809 for the three months ended March 31, 2001 compared to
$10,857 for the same period in 2000, a decrease of $3,048, or 28%. This decrease
was primarily due to a decrease in oil production of 557 barrels for the period
ended March 31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $22,609 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase of $5,337 in oil and gas sales receipts,
reductions in working capital of $10,464, abandoned property costs of $6,855 and
production costs of $59, offset by an increase in G&A expenses of $106. The
increase in oil and gas receipts resulted from the increase in commodity prices


                                        7

   533


during 2001 which contributed an additional $29,315 to oil and gas receipts,
offset by $23,978 resulting from the decline in production during 2001 as
compared to the same period in 2000. The decrease in production costs was
primarily due to lower well maintenance costs, offset by higher production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to an increase in the accrual for tax preparation fees.

Net Cash Provided by Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from disposition of assets during the three months ended March 31, 2000
of $23,867 were related to salvage income received on one well plugged and
abandoned during 2000.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $94,553, of which $946 was distributed to the managing general partner and
$93,607 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $78,309, of which $783 was distributed to the
managing general partner and $77,526 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.

                                        8


   534
                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   535



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Private Investment 85-A, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley Private Investment 85-A,
Ltd. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Private
Investment 85-A, Ltd. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.




                                             Ernst & Young LLP


Dallas, Texas
March 9, 2001




                                       2
   536


                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                                                   2000                1999
                                                                                             ----------------    ----------------
                     ASSETS
                     ------

                                                                                                           
Current assets:
   Cash                                                                                      $       74,084      $        79,497
   Accounts receivable - oil and gas sales                                                           68,251               45,956
                                                                                               ------------        -------------

            Total current assets                                                                    142,335              125,453
                                                                                               ------------        -------------

Oil and gas properties - at cost, based on the
   successful efforts accounting method                                                           3,399,009            4,113,242
Accumulated depletion                                                                            (2,780,814)          (3,391,494)
                                                                                               ------------        -------------

            Net oil and gas properties                                                              618,195              721,748
                                                                                               ------------        -------------

                                                                                             $      760,530      $       847,201
                                                                                              =============       ==============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
   Accounts payable - affiliate                                                              $        5,818      $         8,160

Partners' capital:
   Managing general partner                                                                           9,957               10,800
   Limited partners (125 interests)                                                                 744,755              828,241
                                                                                               ------------        -------------

                                                                                                    754,712              839,041
                                                                                               ------------        -------------

                                                                                             $      760,530      $       847,201
                                                                                              =============       ==============
















   The accompanying notes are an integral part of these financial statements.



                                       3
   537

                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                       2000        1999          1998
                                                     ---------   ---------     ---------

                                                                      
Revenues:
   Oil and gas                                       $ 502,432   $ 342,760    $  269,068
   Interest                                              6,051       3,587         3,856
   Gain on disposition of assets                        33,459          --            --
                                                     ---------   ---------    ----------

                                                       541,942     346,347       272,924
                                                     ---------   ---------    ----------

Costs and expenses:
   Oil and gas production                              164,183     157,138       173,592
   General and administrative                           10,049       6,855         6,018
   Impairment of oil and gas properties                 61,942          --       130,873
   Depletion                                            35,049      65,329       131,389
   Abandoned property                                    7,038          --            --
                                                     ---------   ---------    ----------

                                                       278,261     229,322       441,872
                                                     ---------   ---------    ----------

Net income (loss)                                    $ 263,681   $ 117,025    $ (168,948)
                                                     =========   =========    ==========

Allocation of net income (loss):
   Managing general partner                          $   2,637   $   1,170    $   (1,689)
                                                     =========   =========    ==========

   Limited partners                                  $ 261,044   $ 115,855    $ (167,259)
                                                     =========   =========    ==========

Net income (loss) per limited partnership interest   $2,088.35   $  926.84    $(1,338.07)
                                                     =========   =========    ==========









   The accompanying notes are an integral part of these financial statements.



                                       4
   538

                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                                           Managing
                                                                           general              Limited
                                                                           partner              partners               Total
                                                                        -------------        --------------       ---------------



                                                                                                        
Partners' capital at January 1, 1998                                    $      13,952        $    1,140,211      $    1,154,163

   Distributions                                                               (1,142)             (112,983)           (114,125)

   Net loss                                                                    (1,689)             (167,259)           (168,948)
                                                                          -----------          ------------        ------------

Partners' capital at December 31, 1998                                         11,121               859,969             871,090

   Distributions                                                               (1,491)             (147,583)           (149,074)

   Net income                                                                   1,170               115,855             117,025
                                                                          -----------          ------------        ------------

Partners' capital at December 31, 1999                                         10,800               828,241             839,041

   Distributions                                                               (3,480)             (344,530)           (348,010)

   Net income                                                                   2,637               261,044             263,681
                                                                          -----------          ------------        ------------

Partners' capital at December 31, 2000                                  $       9,957        $      744,755      $      754,712
                                                                         ============         =============       =============











   The accompanying notes are an integral part of these financial statements.



                                       5
   539


                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                                             2000                 1999                1998
                                                                        --------------       --------------      --------------

                                                                                                        
Cash flows from operating activities:
    Net income (loss)                                                   $     263,681        $     117,025       $    (168,948)
    Adjustments to reconcile net income (loss) to
       net cash provided by operating activities:
           Impairment of oil and gas properties                                61,942                  -               130,873
           Depletion                                                           35,049               65,329             131,389
           Gain on disposition of assets                                      (33,459)                 -                   -
    Changes in assets and liabilities:
           Accounts receivable                                                (22,295)              (7,696)              9,222
           Accounts payable                                                    (2,342)               1,422               2,238
                                                                          -----------          -----------         -----------

              Net cash provided by operating activities                       302,576              176,080             104,774
                                                                          -----------          -----------         -----------

Cash flows used in investing activities:
    Additions to oil and gas properties                                        (1,948)              (6,572)             (1,756)
    Proceeds from disposition of assets                                        41,969                  -                   -
                                                                          -----------          -----------         -----------

              Net cash provided (used by) investing
                 activities                                                    40,021               (6,572)             (1,756)
                                                                          -----------          -----------         -----------

Cash flows used in financing activities:
    Cash distributions to partners                                           (348,010)            (149,074)           (114,125)
                                                                          -----------          -----------         -----------

Net increase (decrease) in cash                                                (5,413)              20,434             (11,107)
Cash at beginning of year                                                      79,497               59,063              70,170
                                                                          -----------          -----------         -----------

Cash at end of year                                                     $      74,084        $      79,497       $      59,063
                                                                         ============         ============        ============




   The accompanying notes are an integral part of these financial statements.



                                       6
   540


                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley Private Investment 85-A, Ltd. (the "Partnership") is a
limited partnership organized in 1985 under the laws of the State of Texas.
The Partnership's managing general partner is Pioneer Natural Resources USA,
Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as determined evaluated by independent petroleum
consultants. The carrying amounts of properties sold or otherwise disposed of
and the related allowances for depletion are eliminated from the accounts and
any gain or loss is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   541

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.  IMPAIRMENT OF LONG-LIVED ASSETS

         In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $61,942 and $130,873
related to its



                                       8
   542

proved oil and gas properties during 2000 and 1998, respectively.

NOTE 4.  INCOME TAXES

         The financial statement basis of the Partnership's net assets and
liabilities was $5,983 less than the tax basis at December 31, 2000.

         The following is a reconciliation of net income (loss) per statements
of operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------

                                                                                                        
      Net income (loss) per statements of operations                    $      263,681       $     117,025       $     (168,948)
      Depletion and depreciation provisions for tax
        reporting purposes less than amounts for
        financial reporting purposes                                            32,046              62,742              129,509
      Impairment of oil and gas properties for
        financial reporting purposes                                            61,942                 -                130,873
      Other, net                                                                (7,404)              1,067                 (933)
                                                                          ------------         -----------         ------------

             Net income per Federal income tax returns                  $      350,265       $     180,834       $       90,501
                                                                         =============        ============        =============


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                         
      Development costs                                                 $       1,948        $       6,572        $      1,756
                                                                         ============         ============         ===========


      Capitalized oil and gas properties consist of the following:



                                                                                                   2000                 1999
                                                                                             ----------------     ----------------
                                                                                                            
      Proved properties:
        Property acquisition costs                                                           $      102,103       $      102,995
        Completed wells and equipment                                                             3,296,906            4,010,247
                                                                                               ------------         ------------

                                                                                                  3,399,009            4,113,242
      Accumulated depletion                                                                      (2,780,814)          (3,391,494)
                                                                                               ------------         ------------

                    Net oil and gas properties                                               $      618,195       $      721,748
                                                                                              =============        =============




                                       9
   543



NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                         
      Payment of lease operating and supervision
        charges in accordance with standard industry
        operating agreements                                            $      66,336        $      73,804        $     78,418
      Reimbursement of general and administrative
        expenses                                                        $       8,067        $       3,581        $      4,294


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and the Partnership are parties to the Program agreement.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnership as follows:



                                                                                        Pioneer USA (1)             Partnership
                                                                                      -------------------         ---------------
                                                                                                           
      Revenues:
        Proceeds from disposition of depreciable
           properties                                                                       9.09091%                 90.90909%
        All other revenues                                                                 24.242425%                75.757575%

      Costs and expenses:
        Lease acquisition costs, drilling and completion
           costs and all other costs                                                        9.09091%                 90.90909%
        Operating costs, direct costs and general and
           administrative expenses                                                         24.242425%                75.757575%


        (1)     Excludes Pioneer USA's 1% general partner ownership which is
                allocated at the Partnership level.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.








                                       10
   544




                                                                             Oil and NGLs                   Gas
                                                                                 (bbls)                    (mcf)
                                                                          --------------------      -------------------

                                                                                                
      Net proved reserves at January 1, 1998                                      271,658                   288,529
      Revisions                                                                   (91,942)                  (76,028)
      Production                                                                  (21,200)                  (22,343)
                                                                             ------------              ------------

      Net proved reserves at December 31, 1998                                    158,516                   190,158
      Revisions                                                                   180,472                   261,855
      Production                                                                  (20,664)                  (23,218)
                                                                             ------------              ------------

      Net proved reserves at December 31, 1999                                    318,324                   428,795
      Revisions                                                                    27,943                   (50,880)
      Production                                                                  (17,619)                  (20,905)
                                                                             ------------              ------------

      Net proved reserves at December 31, 2000                                    328,648                   357,010
                                                                             ============              ============


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.00 per barrel of NGLs and $7.43 per mcf of gas,
discounted at 10% was approximately $2,408,000 and undiscounted was $5,247,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                                               For the years ended December 31,
                                                                     ----------------------------------------------------
                                                                           2000                1999                1998
                                                                     ----------------    ----------------    ----------------
                                                                                               (in thousands)
                                                                                                   
Oil and gas producing activities:
   Future cash inflows                                               $        10,071     $        7,881     $         1,713
   Future production costs                                                    (4,824)            (4,213)             (1,293)
                                                                       -------------       ------------       -------------

                                                                               5,247              3,668                 420
   10% annual discount factor                                                 (2,839)            (1,850)               (139)
                                                                       -------------       ------------       -------------

   Standardized measure of discounted future net cash flows          $         2,408     $        1,818     $           281
                                                                      ==============      =============      ==============




                                       11
   545



                                                                               For the years ended December 31,
                                                                     ----------------------------------------------------
                                                                           2000                1999                1998
                                                                     ----------------    ----------------    ----------------
                                                                                               (in thousands)
                                                                                                   
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs                     $          (338)    $         (186)    $          (95)
      Net changes in prices and production costs                                 820                905               (674)
      Revisions of previous quantity estimates                                   130              1,414               (124)
      Accretion of discount                                                      182                 28                109
      Changes in production rates, timing and other                             (204)              (624)               (21)
                                                                       -------------       ------------       ------------

      Change in present value of future net revenues                             590              1,537               (805)
                                                                       -------------       ------------       ------------

      Balance, beginning of year                                               1,818                281              1,086
                                                                       -------------       ------------       ------------

      Balance, end of year                                           $         2,408     $        1,818     $          281
                                                                      ==============      =============      =============


NOTE 8.  MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:


                                                                                 2000               1999                1998
                                                                               --------           --------            --------

                                                                                                              
                    Plains Marketing, L.P.                                       64%                60%                  -
                    Genesis Crude Oil, L.P.                                       -                  -                  63%
                    Western Gas Resources, Inc.                                   3%                 6%                 25%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $27,002 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.


NOTE 9. PARTNERSHIP AGREEMENT

         The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Partnership affairs. As managing
        general partner and operator of the Partnership's properties, all
        production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion



                                       12
   546

        of the oil and gas revenue is initially received by Pioneer USA prior to
        being paid to the Partnership. Under the limited partnership agreement,
        the managing general partner pays 1% of the Partnership's acquisition,
        drilling and completion costs and 1% of its operating and general and
        administrative expenses. In return, it is allocated 1% of the
        Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $5,000,000. Pioneer USA was required to contribute amounts equal to 1%
        of initial Partnership capital less commission and organization and
        offering costs allocated to the limited partners and to contribute
        amounts necessary to pay costs and expenses allocated to it under the
        Partnership agreement to the extent its share of revenues does not cover
        such costs.






                                       13




   547
                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
    RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 47% to $502,432 for 2000 as
compared to $342,760 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 11,945
barrels of oil, 5,674 barrels of natural gas liquids ("NGLs") and 20,905 mcf of
gas were sold, or 21,103 barrel of oil equivalents ("BOEs"). In 1999, 14,568
barrels of oil, 6,096 barrels of NGLs and 23,218 mcf of gas were sold, or 24,534
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $13.28, or 79%, from
$16.91 in 1999 to $30.19 in 2000. The average price received per barrel of NGLs
increased $5.27, or 53%, from $9.95 in 1999 to $15.22 in 2000. The average price
received per mcf of gas increased 72% from $1.54 in 1999 to $2.65 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets recognized during 2000 of $33,459 was due to
equipment credits received on two wells plugged and abandoned during the current
year. Abandoned property costs of $7,038 incurred in 2000 related to the
abandonment of these two wells.

Total costs and expenses increased in 2000 to $278,261 as compared to $229,322
in 1999, an increase of $48,939, or 21%. The increase was primarily due to the
impairment of oil and gas properties and increases in production costs,
abandoned property costs and general and administrative expenses ("G&A"), offset
by a decline in depletion.

Production costs were $164,183 in 2000 and $157,138 in 1999, resulting in a
$7,045 increase, or 4%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and workover costs incurred to
stimulate well production, offset by a decline in well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
47% from $6,855 in 1999 to $10,049 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 2% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $8,067 in 2000 and $3,581 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.


In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $61,942 related to its oil and gas properties during 2000.


   548

Depletion was $35,049 in 2000 as compared to $65,329 in 1999, representing a
decrease of $30,280, or 46%. This decrease was primarily due to a 20,767 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices and a decline in oil production of 2,623 barrels for the period ended
December 31, 2000 compared to the same period in 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 27% to $342,760 from
$269,068 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 14,568 barrels of oil,
6,096 barrels of NGLs and 23,218 mcf of gas were sold, or 24,534 BOEs. In 1998,
14,874 barrels of oil, 6,326 barrels of NGLs and 22,343 mcf of gas were sold, or
24,924 BOEs.

The average price received per barrel of oil increased $3.71, or 28%, from
$13.20 in 1998 to $16.91 in 1999. The average price received per barrel of NGLs
increased $3.46, or 53%, from $6.49 in 1998 to $9.95 in 1999. The average price
received per mcf of gas increased 9% from $1.41 in 1998 to $1.54 in 1999.

Total costs and expenses decreased in 1999 to $229,322 as compared to $441,872
in 1998, a decrease of $212,550, or 48%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $157,138 in 1999 and $173,592 in 1998, resulting in a
$16,454 decrease, or 9%. The decrease was due to declines in well maintenance
costs and ad valorem taxes.

During this period, G&A increased 14% from $6,018 in 1998 to $6,855 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 2% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $3,581 in
1999 and $4,294 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $130,873 related to its
oil and gas properties during 1998.

Depletion was $65,329 in 1999 compared to $131,389 in 1998, representing a
decrease of $66,060, or 50%. This decrease was the result of an increase in
proved reserves of 120,513 barrels of oil during 1999 due to higher commodity
prices and a reduction in the Partnership's net depletable basis from charges
taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.





   549
Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $126,496 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $162,136, offset by increases in production costs paid
of $7,045, G&A expenses paid of $3,194, abandoned property costs paid of $7,038
and working capital of $18,363. The increase in oil and gas receipts resulted
from the increase in commodity prices during 2000 which contributed an
additional $253,878 to oil and gas receipts, offset by $91,742 resulting from
the decline in production during 2000. The increase in production costs was
primarily due to increased production taxes associated with higher oil and gas
prices and workover costs incurred to stimulate well production, offset by a
decline in well maintenance costs. The increase in G&A was primarily due to
higher percentage of the managing general partner's G&A being allocated (limited
to 2% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds from disposition of assets during 2000 of $41,969 were related to
$33,459 salvage income received on two wells plugged and abandoned during the
current year and $8,510 from equipment credits received on one active well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $348,010, of which $3,480 was
distributed to the managing general partner and $344,530 to the limited
partners. In 1999, cash distributions to the partners were $149,074, of which
$1,491 was distributed to the managing general partner and $147,583 to the
limited partners.








   550




                 PARKER & PARSLEY PRIVATE INVESTMENT 85-A, LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  118,048   $  502,432   $  342,760   $  269,068   $  396,312   $  474,256
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   61,942   $       --   $  130,873   $  154,523   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   83,840   $  263,681   $  117,025   $ (168,948)  $  (35,440)  $  214,177
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      838   $    2,637   $    1,170   $   (1,689)  $     (354)  $    2,142
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   83,002   $  261,044   $  115,855   $ (167,259)  $  (35,086)  $  212,035
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   664.02   $ 2,088.35   $   926.84   $(1,338.07)  $  (280.69)  $ 1,696.28
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   620.21   $ 2,756.24   $ 1,180.66   $   903.86   $ 1,914.33   $ 2,012.00
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  850,756   $  760,530   $  847,201   $  877,828   $1,158,663   $1,438,725
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   551
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

             PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.,
                          A TEXAS LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Selected 85 Private Investment, Ltd. and supplements the proxy
statement/prospectus dated      , 2001, of Pioneer Natural Resources Company and
Pioneer Natural Resources USA, Inc., by which Pioneer USA is soliciting proxies
to be voted at a special meeting of limited partners of the partnership. The
purpose of the special meeting is for you to vote upon the merger of the
partnership with and into Pioneer USA that, if completed, will result in your
receiving common stock of Pioneer Natural Resources Company for your partnership
interests.


     This document contains the following information concerning Parker &
Parsley Private Selected 85 Private Investment, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-

   552
              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $   4,690

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   4,536

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $     883
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  191.57

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.07 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $  107.35

          --  as of December 31, 2000 (c)                                                     $  110.65

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  180.40

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  185.82

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     215
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2035, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-

   553

              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001

   554

              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS



                                                     March 31,      December 31,
                                                       2001             2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS

                                                              
Current assets:
  Cash                                              $    31,972     $    32,773
  Accounts receivable - oil and gas sales                70,327          78,218
                                                    -----------     -----------
        Total current assets                            102,299         110,991
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                3,864,140       3,864,140
Accumulated depletion                                (3,448,354)     (3,441,568)
                                                    -----------     -----------
        Net oil and gas properties                      415,786         422,572
                                                    -----------     -----------
                                                    $   518,085     $   533,563
                                                    ===========     ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $     6,874     $     6,722

Partners' capital:
  Managing general partner                                7,735           7,892
  Limited partners (117 interests)                      503,476         518,949
                                                    -----------     -----------
                                                        511,211         526,841
                                                    -----------     -----------
                                                    $   518,085     $   533,563
                                                    ===========     ===========


  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        2

   555

              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                          Three months ended
                                                                March 31,
                                                       -----------------------
                                                          2001          2000
                                                       ---------     ---------

                                                               
Revenues:
  Oil and gas                                          $ 128,977     $  89,527
  Interest                                                   780           592
  Gain on disposition of assets                            2,574            --
                                                       ---------     ---------
                                                         132,331        90,119
                                                       ---------     ---------
Costs and expenses:
  Oil and gas production                                  50,331        40,320
  General and administrative                               2,579         1,791
  Depletion                                                6,786         8,093
                                                       ---------     ---------
                                                          59,696        50,204
                                                       ---------     ---------
Net income                                             $  72,635     $  39,915
                                                       =========     =========
Allocation of net income:
  Managing general partner                             $     726     $     399
                                                       =========     =========
  Limited partners                                     $  71,909     $  39,516
                                                       =========     =========
Net income per limited partnership interest            $  614.61     $  337.74
                                                       =========     =========


       The financial information included herein has been prepared by the
    managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.

                                        3

   556

              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)



                                     Managing
                                      general        Limited
                                      partner        partners         Total
                                     ---------     -----------     -----------

                                                          
Balance at January 1, 2001           $   7,892     $   518,949     $   526,841

    Distributions                         (883)        (87,382)        (88,265)

    Net income                             726          71,909          72,635
                                     ---------     -----------     -----------

Balance at March 31, 2001            $   7,735     $   503,476     $   511,211
                                     =========     ===========     ===========



       The financial information included herein has been prepared by the
    managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.

                                        4

   557

              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                          Three months ended
                                                               March 31,
                                                      -------------------------
                                                         2001           2000
                                                      ----------     ----------
                                                               
Cash flows from operating activities:
  Net income                                          $   72,635     $   39,915
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                           6,786          8,093
       Gain on disposition of assets                      (2,574)            --
  Changes in assets and liabilities:
       Accounts receivable                                 7,891         10,003
       Accounts payable                                      152            859
                                                      ----------     ----------
         Net cash provided by operating activities        84,890         58,870
                                                      ----------     ----------
Cash flows from investing activities:
  Additions to oil and gas properties                         --           (884)
  Proceeds from disposition of assets                      2,574             --
                                                      ----------     ----------
         Net cash provided by (used in) investing
            activities                                     2,574           (884)
                                                      ----------     ----------
Cash flows used in financing activities:
  Cash distributions to partners                         (88,265)       (43,494)
                                                      ----------     ----------
Net increase (decrease) in cash                             (801)        14,492
Cash at beginning of period                               32,773         39,610
                                                      ----------     ----------
Cash at end of period                                 $   31,972     $   54,102
                                                      ==========     ==========


       The financial information included herein has been prepared by the
    managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.

                                        5

   558

              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley Selected 85 Private Investment, Ltd. (the "Partnership") is a
limited partnership organized in 1985 under the laws of the State of Texas.

The Partnership engages oil and gas development and production in Texas and is
not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 44% to $128,977 for the three
months ended March 31, 2001 as compared to $89,527 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 2,541 barrels
of oil, 1,191 barrels of natural gas liquids ("NGLs") and 6,584 mcf of gas were
sold, or 4,829 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 2,270 barrels of oil, 1,355 barrels of NGLs and 5,393 mcf of gas
were sold, or 4,524 BOEs.

                                        6

   559

The average price received per barrel of oil increased $.99, or 4%, from $27.34
for the three months ended March 31, 2000 to $28.33 for the same period in 2001.
The average price received per barrel of NGLs increased $4.69, or 35%, from
$13.50 for the three months ended March 31, 2000 to $18.19 for the same period
in 2001. The average price received per mcf of gas increased 216% from $1.70
during the three months ended March 31, 2000 to $5.37 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $2,574 was recognized during the three months
ended March 31, 2001 resulting from equipment credits received on one fully
depleted well.

Costs and Expenses:

Total costs and expenses increased to $59,696 for the three months ended March
31, 2001 as compared to $50,204 for the same period in 2000, an increase of
$9,492, or 19%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $50,331 for the three months ended March 31, 2001 and
$40,320 for the same period in 2000 resulting in a $10,011 increase, or 25%. The
increase was due to higher production taxes associated with higher oil and gas
prices and additional well maintenance costs incurred to stimulate well
production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 44% from $1,791 for the three months ended March 31, 2000 to $2,579
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $6,786 for the three months ended March 31, 2001 as compared to
$8,093 for the same period in 2000, a decrease of $1,307, or 16%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices, offset by an
increase in oil production of 271 barrels for the period ended March 31, 2001 as
compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $26,020 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase of $39,638 in oil and gas sales receipts, offset
by increases in production costs of $10,011, G&A expenses of $788 and working

                                        7

   560

capital of $2,819. The increase in oil and gas receipts resulted from the
increase in commodity prices during 2001 which contributed an additional $28,552
to oil and gas receipts and $11,086 resulting from an increase in production
during 2001 as compared to the same period in 2000. The increase in production
costs was primarily due to increased production taxes associated with higher oil
and gas prices and well maintenance costs incurred to stimulate well production.
The increase in G&A was primarily due to an increase in the accrual for tax
preparation fees.

Net Cash Provided by (Used in) Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from disposition of assets of $2,574 received during the three months
ended March 31, 2001 were due to equipment credits received on one fully
depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $88,265, of which $883 was distributed to the managing general partner and
$87,382 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $43,494, of which $435 was distributed to the
managing general partner and $43,059 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.

                                        8
   561
              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999





   562



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Selected 85 Private Investment, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley Selected 85 Private
Investment, Ltd. as of December 31, 2000 and 1999, and the related statements of
operations, partners' capital and cash flows for each of the three years in the
period ended December 31, 2000. These financial statements are the
responsibility of the Partnership's management. Our responsibility is to express
an opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Selected 85
Private Investment, Ltd. as of December 31, 2000 and 1999, and the results of
its operations and its cash flows for each of the three years in the period
ended December 31, 2000, in conformity with accounting principles generally
accepted in the United States.



                                           Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       2
   563



              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31






                                                        2000        1999
                                                      ---------   ---------
           ASSETS

                                                         
Current assets:
 Cash                                                 $  32,773   $  39,610
 Accounts receivable - oil and gas sales                 78,218      45,630
                                                      ---------   ---------

       Total current assets                             110,991      85,240
                                                      ---------   ---------

Oil and gas properties - at cost, based on
 the successful efforts accounting method             3,864,140   3,859,832
Accumulated depletion                                (3,441,568) (3,408,713)
                                                      ---------   ---------
       Net oil and gas properties                       422,572     451,119
                                                        -------   ---------

                                                     $  533,563  $  536,359
                                                        =======   =========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
 Accounts payable - affiliate                        $    6,722  $    8,178

Partners' capital:
 Managing general partner                                 7,892       7,905
 Limited partners (117 interests)                       518,949     520,276
                                                        -------   ---------

                                                        526,841     528,181

                                                     $ 533,563   $  536,359
                                                       ========   =========






   The accompanying notes are an integral part of these financial statements.



                                       3
   564



              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                              2000       1999        1998
                                             --------   -------     -------
                                                        
Revenues:
 Oil and gas                               $ 441,200  $ 252,399  $  206,099
 Interest                                      3,585      1,728       2,200
                                             -------    -------     -------
                                             444,785    254,127     208,299
                                             -------    -------     -------

Costs and expenses:
 Oil and gas production                      184,074    153,832     153,789
 General and administrative                    8,824      5,048       4,122
 Impairment of oil and gas properties           -           -        92,133
 Depletion                                    31,732     33,899     118,737
                                             -------    -------     -------

                                             224,630    192,779     368,781
                                             -------    -------     -------

Net income (loss)                          $ 220,155  $  61,348  $ (160,482)
                                             -------    -------     -------

Allocation of net income (loss):
 Managing general partner                  $   2,202  $     613  $   (1,605)
                                             =======    =======     =======

 Limited partners                          $ 217,953  $  60,735  $ (158,877)
                                             =======    =======     =======

Net income (loss) per limited
  partnership interest                     $1,862.85  $  519.10  $(1,357.92)
                                            ========    =======    ========







   The accompanying notes are an integral part of these financial statements.



                                       4
   565



              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                          Managing
                                           general      Limited
                                           partner      partners    Total
                                          --------      --------    -----


                                                          
Partners' capital at January 1, 1998     $  10,253   $  752,707  $  762,960

  Distributions                               (756)     (74,884)   (75,640)

  Net loss                                  (1,605)    (158,877)   (160,482)
                                            ------     --------    --------

Partners' capital at December 31, 1998       7,892      518,946    526,838

  Distributions                               (600)     (59,405)   (60,005)

  Net income                                   613       60,735      61,348
                                            ------     --------    --------

Partners' capital at December 31, 1999       7,905      520,276     528,181

  Distributions                             (2,215)    (219,280)   (221,495)

  Net income                                 2,202      217,953     220,155
                                            ------     --------    --------

Partners' capital at December 31, 2000   $   7,892   $  518,949  $  526,841
                                           =======      =======     =======






   The accompanying notes are an integral part of these financial statements.



                                       5
   566



              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                         2000        1999       1998
                                                        -------     ------    -------

                                                                    
Cash flows from operating activities:
 Net income (loss)                                   $  220,155   $  61,348   $ (160,482)
 Adjustments to reconcile net income (loss) to
   net cash provided by operating activities:
     Impairment of oil and gas properties                   -           -         92,133
     Depletion                                           31,732      33,899      118,737
 Changes in assets and liabilities:
     Accounts receivable                                (32,588)    (22,369)      20,237
     Accounts payable                                    (1,456)      2,063       (3,647)
                                                       --------      ------      -------

        Net cash provided by operating activities       217,843      74,941       66,978
                                                       --------      ------      -------
Cash flows from investing activities:
 Additions to oil and gas properties                     (3,185)     (3,269)      (4,417)
 Proceeds from asset dispositions                          -           -           3,057
                                                       --------      ------      -------

        Net cash used in investing activities            (3,185)     (3,269)      (1,360)
                                                       --------      ------      -------
Cash flows used in financing activities:
 Cash distributions to partners                        (221,495)    (60,005)     (75,640)
                                                       --------      ------      -------

Net increase (decrease) in cash                          (6,837)     11,667      (10,022)
Cash at beginning of year                                39,610      27,943       37,965
                                                       --------      ------      -------

Cash at end of year                                  $   32,773   $  39,610   $   27,943
                                                       ========      ======      =======




   The accompanying notes are an integral part of these financial statements.



                                       6
   567



              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.     ORGANIZATION AND NATURE OF OPERATIONS

     Parker & Parsley Selected 85 Private Investment, Ltd. (the
"Partnership") is a limited partnership organized in 1985 under the laws of
the State of Texas.  The Partnership's managing general partner is Pioneer
Natural Resources USA, Inc. ("Pioneer USA").

     The Partnership engages oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

NOTE 2.     SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

     A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

     Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

     Impairment of long-lived assets - In accordance with Statement of Financial
Accounting Standards No. 121, "Accounting for the Impairment of Long-Lived
Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

     Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.


     Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

     Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the

                                       7
   568

respective partners.

     Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

     General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

     Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

     Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

     Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $92,133 related to its
proved oil and gas properties during 1998.

                                       8
   569

NOTE 4.    INCOME TAXES

     The financial statement basis of the Partnership's net assets and
liabilities was $152,466 less than the tax basis at December 31, 2000.

     The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                          2000       1999       1998
                                                        --------    -------   --------

                                                                   
   Net income (loss) per statements of operations      $ 220,155   $ 61,348 $ (160,482)
   Depletion and depreciation provisions for tax
     reporting purposes less than amounts for
     financial reporting purposes                         28,649     30,978    116,164
   Impairment of oil and gas properties for financial
     reporting purposes                                     -          -        92,133
   Salvage income                                           -          -         2,904
   Other, net                                               (493)      (727)       859

        Net income per Federal income tax returns      $ 248,311   $ 91,599 $   51,578
                                                        ========    =======   ========


NOTE 5.     OIL AND GAS PRODUCING ACTIVITIES

     The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:





                                             2000       1999        1998
                                            ------     -------     -------

                                                         
     Development costs                     $ 3,185    $  3,269    $  4,417
                                            ======     =======     =======


     Capitalized oil and gas properties consist of the following:




                                                         2000           1999
                                                        ---------     ---------
                                                              
     Proved properties:
       Property acquisition costs                     $   141,791   $   141,791
       Completed wells and equipment                    3,722,349     3,718,041
                                                        ---------     ---------

                                                        3,864,140     3,859,832
     Accumulated depletion                             (3,441,568)   (3,408,713)

           Net oil and gas properties                 $   422,572   $   451,119
                                                        =========     =========







                                       9
   570



NOTE 6.     RELATED PARTY TRANSACTIONS

     Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                       2000        1999          1998
                                                     --------    --------      --------

                                                                    
   Payment of lease operating and supervision
     charges in accordance with standard industry
     operating agreements                           $  66,669  $  78,823      $  77,025
   Reimbursement of general and administrative
     expenses                                       $   6,888  $   1,886      $   2,442


   The Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Pioneer USA and
the Partnership are parties to the Program agreement.

   The costs and revenues of the Program are allocated to the Partnership and
Pioneer USA as follows:





                                                     Pioneer USA (1)  Partnership
                                                     --------------   -----------


                                                            
  Revenues:
    Proceeds from disposition of depreciable
     properties                                         9.09091%      90.90909%
    All other revenues                                24.242425%     75.757575%
  Costs and expenses:
    Lease acquisition costs, drilling and completion
     costs and all other costs                          9.09091%      90.90909%
    Operating costs, direct costs and general and
     administrative expenses                          24.242425%     75.757575%


   (1) Excludes Pioneer USA's 1% general partner ownership which is allocated at
       the Partnership level.

NOTE 7.     OIL AND GAS INFORMATION (UNAUDITED)

     The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                       10
   571





                                                   Oil and NGLs          Gas
                                                     (bbls)             (mcf)
                                                   ------------       ----------


                                                                  
   Net proved reserves at January 1, 1998            186,210            271,087
   Revisions                                         (76,968)           (74,549)
   Production                                        (15,439)           (25,328)
                                                    --------           --------

   Net proved reserves at December 31, 1998           93,803            171,210
   Revisions                                         121,880            243,365
   Production                                        (14,598)           (27,627)
                                                    --------           --------

   Net proved reserves at December 31, 1999          201,085            386,948
   Revisions                                          46,612             21,005
   Production                                        (15,698)           (22,987)
                                                    --------           --------

   Net proved reserves at December 31, 2000          231,999            384,966
                                                    ========           ========


     As of December 31, 2000, the estimated present value of future net revenues
of proved reserves, calculated using December 31, 2000 prices of $26.63 per
barrel of oil, $13.32 per barrel of NGLs and $7.55 per mcf of gas, discounted at
10% was approximately $1,829,000 and undiscounted was approximately $3,687,000.

     Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

    The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

    Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.





                                              For the years ended December 31,
                                              --------------------------------

                                                2000        1999       1998
                                              ---------  ----------  ---------
                                                      (in thousands)

                                                           
Oil and gas producing activities:
  Future cash inflows                         $  7,746   $   4,941   $  1,023
  Future production costs                       (4,059)     (2,870)      (797)
                                                ------     -------     ------

                                                 3,687       2,071        226
  10% annual discount factor                    (1,858)       (980)       (69)
                                                ------     -------     ------

  Standardized measure of discounted
    future net cash flows                     $  1,829   $   1,091   $    157
                                                ======     =======     ======



                                       11
   572



                                                For the years ended December 31,
                                                --------------------------------
                                                  2000        1999       1998
                                                ---------  ----------  ---------
                                                         (in thousands)
                                                               
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs   $ (257)    $   (98)    $  (53)
    Net changes in prices and production costs      658         492       (426)
    Revisions of previous quantity estimates        328         882        (98)
    Accretion of discount                           109          16         70
    Changes in production rates, timing and
      other                                        (100)       (358)       (32)
                                                 ------     -------     ------
    Change in present value of future net
      revenues                                      738         934       (539)
                                                 ------     -------     ------
    Balance, beginning of year                    1,091         157        696
                                                 ------     -------     ------
    Balance, end of year                        $ 1,829   $   1,091   $    157
                                                 ======     =======     ======


NOTE 8.    MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:





                                                2000       1999        1998
                                              --------   --------    --------

                                                            
            Plains Marketing, L.P.               57%        49%       -
            Koch Midstream Services Company       9%        11%       -
            NGTS LLC                              9%        10%       -
            Western Gas Resources, Inc.           4%        10%     34%
            Genesis Crude Oil, L.P.               -          -      52%


     At December 31, 2000, the amount receivable from Plains Marketing, L.P. was
$26,039, which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

     Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.


NOTE 9.     PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

     Managing general partner - The managing general partner of the Partnership
     is Pioneer USA. Pioneer USA has the power and authority to manage, control
     and administer all Partnership affairs. As managing general partner and
     operator of the Partnership's properties, all production expenses are
     incurred by Pioneer USA and billed to the Partnership. The majority of the
     Partnership's oil and gas revenues are received directly by the
     Partnership, however, a portion of the oil and gas revenue is initially
     received by Pioneer USA prior to being paid to the



                                       12
   573
     Partnership. Under the limited partnership agreement, the managing general
     partner pays 1% of the Partnership's acquisition, drilling and completion
     costs and 1% of its operating and general and administrative expenses. In
     return, it is allocated 1% of the Partnership's revenues.

     Limited partner liability - The maximum amount of liability of any limited
     partner is the total contributions of such partner plus his share of any
     undistributed profits.

     Initial capital contributions - The limited partners entered into
     subscription agreements for aggregate capital contributions of $4,690,000.
     Pioneer USA was required to contribute amounts equal to 1% of initial
     Partnership capital less commission and organization and offering costs
     allocated to the limited partners and to contribute amounts necessary to
     pay costs and expenses allocated to it under the Partnership agreement to
     the extent its share of revenues does not cover such costs.




                                       13
   574


              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 75% to $441,200 for 2000 as
compared to $252,399 in 1999. The increase in revenues resulted from higher
average prices received and a slight increase in production. In 2000, 9,509
barrels of oil, 6,189 barrels of natural gas liquids ("NGLs") and 22,987 mcf of
gas were sold, or 19,529 barrel of oil equivalents ("BOEs"). In 1999, 7,828
barrels of oil, 6,770 barrels of NGLs and 27,627 mcf of gas were sold, or 19,203
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.32, or 71%, from
$17.27 in 1999 to $29.59 in 2000. The average price received per barrel of NGLs
increased $5.03, or 48%, from $10.49 in 1999 to $15.52 in 2000. The average
price received per mcf of gas increased 66% from $1.67 in 1999 to $2.77 in 2000.
The market price for oil and gas has been extremely volatile in the past decade,
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $224,630 as compared to $192,779
in 1999, an increase of $31,851, or 17%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $184,074 in 2000 and $153,832 in 1999, resulting in a
$30,242 increase, or 20%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and workover costs incurred to
stimulate well production, offset by a decline in well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
75% from $5,048 in 1999 to $8,824 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 2% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $6,888 in 2000 and $1,886 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $31,732 in 2000 as compared to $33,899 in 1999, representing a
decrease of $2,167, or 6%. This decrease was primarily due to a 28,956 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices, offset by an increase in oil production of 1,681 barrels for the period
ended December 31, 2000 compared to the same period in 1999.


   575


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 22% to $252,399 from
$206,099 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 7,828 barrels of oil,
6,770 barrels of NGLs and 27,627 mcf of gas were sold, or 19,203 BOEs. In 1998,
9,075 barrels of oil, 6,364 barrels of NGLs and 25,328 mcf of gas were sold, or
19,660 BOEs.

The average price received per barrel of oil increased $3.83, or 28%, from
$13.44 in 1998 to $17.27 in 1999. The average price received per barrel of NGLs
increased $3.50, or 50%, from $6.99 in 1998 to $10.49 in 1999. The average price
received per mcf of gas increased 7% from $1.56 in 1998 to $1.67 in 1999.

Total costs and expenses decreased in 1999 to $192,779 as compared to $368,781
in 1998, a decrease of $176,002, or 48%. The decrease was primarily due to
declines in the impairment of oil and gas properties and depletion, offset by
increases in G&A and production costs.

Production costs were $153,832 in 1999 and $153,789 in 1998, resulting in a $43
increase. The increase was due to increases in production taxes due to increased
oil and gas revenues and additional well maintenance costs incurred to stimulate
well production, offset by a decline in ad valorem taxes.

During this period, G&A increased 22% from $4,122 in 1998 to $5,048 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 2% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $1,886 in
1999 and $2,442 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $92,133 related to its oil and gas properties during 1998.

Depletion was $33,899 in 1999 compared to $118,737 in 1998, representing a
decrease of $84,838, or 71%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 65,798 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 1,247
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

   576


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $142,902 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $190,658, offset by increases in production costs paid
of $30,242, G&A expenses paid of $3,776 and working capital of $13,738. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $162,805 to oil and gas receipts and
an increase of $27,853 resulting from the increase in production during 2000.
The increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and workover costs incurred to
stimulate well production, offset by a decline in well maintenance costs.. The
increase in G&A was primarily due to higher percentage of the managing general
partner's G&A being allocated (limited to 2% of oil and gas revenues) as a
result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on various oil and gas properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $221,495, of which $2,215 was
distributed to the managing general partner and $219,280 to the limited
partners. In 1999, cash distributions to the partners were $60,005, of which
$600 was distributed to the managing general partner and $59,405 to the limited
partners.








   577





              PARKER & PARSLEY SELECTED 85 PRIVATE INVESTMENT, LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   89,527   $  441,200   $  252,399   $  206,099   $  324,463   $  387,747
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   92,133   $  258,548   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $          $       --   $       --   $       --   $       --   $       --   $   27,488
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   39,915   $  220,155   $   61,348   $ (160,482)  $ (197,320)  $  165,606
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      399   $    2,202   $      613   $   (1,605)  $   (1,973)  $    1,656
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   39,516   $  217,953   $   60,735   $ (158,877)  $ (195,347)  $  163,950
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   337.74   $ 1,862.85   $   519.10   $(1,357.92)  $(1,669.63)  $ 1,401.28
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   368.03   $ 1,874.19   $   507.74   $   640.03   $ 1,393.78   $ 1,583.47(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  533,639   $  533,563   $  536,359   $  532,953   $  772,722   $1,133,345
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


---------

(a)  Including litigation settlement per limited partnership interest of $234.94
     in 1996.



   578
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 86-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
86-A, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 86-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-

   579
                           PARKER & PARSLEY 86-A, LTD.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $  10,131

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $  13,784

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   1,788
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  177.09

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.88 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $   50.26

          --  as of December 31, 2000 (c)                                                     $   58.31

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  164.32

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  171.97

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     225
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2036, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-

   580



                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 33-3353A


                           PARKER & PARSLEY 86-A, LTD.
             (Exact name of Registrant as specified in its charter)


                    Texas                               75-2124884
        --------------------------------           ---------------------
        (State or other jurisdiction of              (I.R.S. Employer
        incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ---------
             (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]




   581



                           PARKER & PARSLEY 86-A, LTD.

                                TABLE OF CONTENTS




                                                                       Page
                          Part I. Financial Information
                                                                 

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000.......................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000............................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001.....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000............................    6

           Notes to Financial Statements..............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations......................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K...........................    9

           Signatures.................................................   10




                                        2

   582



                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,      December 31,
                                                       2001            2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS
                                                              
Current assets:
   Cash                                             $     47,205    $     46,169
   Accounts receivable - oil and gas sales                76,358         150,881
                                                    ------------    ------------
          Total current assets                           123,563         197,050
                                                    ------------    ------------
Oil and gas properties - at cost, based on the
   successful efforts accounting method                7,132,242       7,132,242
Accumulated depletion                                 (6,728,128)     (6,721,529)
                                                    ------------    ------------
          Net oil and gas properties                     404,114         410,713
                                                    ------------    ------------
                                                    $    527,677    $    607,763
                                                    ============    ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable - affiliate                     $     14,635    $     12,398

Partners' capital:
   Managing general partner                                3,823           4,647
   Limited partners (10,131 interests)                   509,219         590,718
                                                    ------------    ------------
                                                         513,042         595,365
                                                    ------------    ------------
                                                    $    527,677    $    607,763
                                                    ============    ============





The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3

   583



                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                         Three months ended
                                                             March 31,
                                                     ---------------------------
                                                         2001           2000
                                                     ------------   ------------
                                                              

Revenues:
   Oil and gas                                       $    219,518   $    196,979
   Interest                                                 1,816          1,140
   Gain on disposition of assets                               --         10,237
                                                     ------------   ------------
                                                          221,334        208,356
                                                     ------------   ------------
Costs and expenses:
   Oil and gas production                                 101,139         89,952
   General and administrative                               4,249          5,909
   Depletion                                                6,599          7,063
                                                     ------------   ------------
                                                          111,987        102,924
                                                     ------------   ------------
Net income                                           $    109,347   $    105,432
                                                     ============   ============
Allocation of net income:
   Managing general partner                          $      1,093   $      1,054
                                                     ============   ============
   Limited partners                                  $    108,254   $    104,378
                                                     ============   ============
Net income per limited partnership interest          $      10.69   $      10.30
                                                     ============   ============





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        4

   584



                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                      Managing
                                       general      Limited
                                       partner      partners       Total
                                     ----------    ----------    ----------
                                                        

Balance at January 1, 2001           $    4,647    $  590,718    $  595,365

   Distributions                         (1,917)     (189,753)     (191,670)

   Net income                             1,093       108,254       109,347
                                     ----------    ----------    ----------

Balance at March 31, 2001            $    3,823    $  509,219    $  513,042
                                     ==========    ==========    ==========





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5
   585



                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                             Three months ended
                                                                  March 31,
                                                         ------------------------
                                                            2001          2000
                                                         ----------    ----------
                                                                 

Cash flows from operating activities:
  Net income                                             $  109,347    $  105,432
  Adjustments to reconcile net income to net
     cash provided by operating activities:
       Depletion                                              6,599         7,063
       Gain on disposition of assets                             --       (10,237)
  Changes in assets and liabilities:
     Accounts receivable                                     74,523       (17,195)
     Accounts payable                                         2,237         2,642
                                                         ----------    ----------
        Net cash provided by operating activities           192,706        87,705
                                                         ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                            --          (658)
  Proceeds from disposition of assets                            --        10,237
                                                         ----------    ----------
        Net cash provided by investing activities                --         9,579
                                                         ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                           (191,670)      (88,643)
                                                         ----------    ----------
Net increase in cash                                          1,036         8,641
Cash at beginning of period                                  46,169        76,838
                                                         ----------    ----------
Cash at end of period                                    $   47,205    $   85,479
                                                         ==========    ==========





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.




                                        6

   586



                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 86-A, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 11% to $219,518 for the three
months ended March 31, 2001 as compared to $196,979 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 3,970
barrels of oil, 2,382 barrels of natural gas liquids ("NGLs") and 10,876 mcf of
gas were sold, or 8,165 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 4,620 barrels of oil, 3,346 barrels of NGLs and 14,461 mcf
of gas were sold, or 10,376 BOEs.



                                        7
   587



The average price received per barrel of oil increased $.74, or 3%, from $27.46
for the three months ended March 31, 2000 to $28.20 for the same period in 2001.
The average price received per barrel of NGLs increased $4.94, or 36%, from
$13.90 for the three months ended March 31, 2000 to $18.84 for the same period
in 2001. The average price received per mcf of gas increased 253% from $1.63
during the three months ended March 31, 2000 to $5.76 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $10,237 was recognized during the three months
ended March 31, 2000 resulting from equipment credits received on one fully
depleted well.

Costs and Expenses:

Total costs and expenses increased to $111,987 for the three months ended March
31, 2001 as compared to $102,924 for the same period in 2000, an increase of
$9,063, or 9%. This increase was primarily due to an increase in production
costs, offset by decreases in general and administrative expenses ("G&A") and
depletion.

Production costs were $101,139 for the three months ended March 31, 2001 and
$89,952 for the same period in 2000 resulting in an $11,187 increase, or 12%.
This increase was primarily due to additional well maintenance and workover
costs incurred to stimulate well production and higher production taxes
associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
decreased 28% from $5,909 for the three months ended March 31, 2000 to $4,249
for the same period in 2001. The decrease is attributable to the Partnership
being credited for an over allocation of $2,337 by the managing general partner
for personnel and administrative costs for the year ended December 31, 2000.

Depletion was $6,599 for the three months ended March 31, 2001 as compared to
$7,063 for the same period in 2000, a decrease of $464, or 7%. This decrease was
primarily due to a decline in oil production of 650 barrels for the period ended
March 31, 2001 as compared to the same period ended March 31, 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $105,001 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to an increase of $23,215 in oil and gas sales receipts and reductions of
$91,313 in working capital and $1,660 in G&A expenses, offset by an increase in
production costs of $11,187. The increase in oil and gas receipts resulted from
the increase in commodity prices during 2001 which contributed an additional
$80,372 to oil and gas receipts, offset by $57,157 resulting from the decline in
production during 2001 as compared to the same period in 2000. The increase in



                                        8

   588



production costs was primarily due to additional well maintenance and workover
costs incurred to stimulate well production and an increase in production taxes
associated with higher oil and gas prices.

Net Cash Provided by Investing Activities

The Partnership's investing activities during the three months ended March 31,
2000 were related to equipment upgrades on active properties.

Proceeds from disposition of assets of $10,237 during the three months ended
March 31, 2000 resulted from equipment credits received on one fully depleted
well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $191,670, of which $1,917 was distributed to the managing general partner
and $189,753 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $88,643, of which $886 was distributed
to the managing general partner and $87,757 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.

                           Part II. Other Information



Item 6.       Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.





                                        9
   589


                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                             PARKER & PARSLEY 86-A, LTD.


                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 8, 2001                By:      /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       10



   590

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 33-3353-A


                           PARKER & PARSLEY 86-A, LTD.
             (Exact name of Registrant as specified in its charter)



                              TEXAS                                                                 75-2124884
            -----------------------------------------                                       --------------------------
                                                                                         
            (State or other jurisdiction of                                                    (I.R.S. Employer
            incorporation or organization)                                                  Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                                      75039
----------------------------------------------------------------                                  -------------
            (Address of principal executive offices)                                                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$10,096,000.

             As of March 8, 2001, the number of outstanding limited
                       partnership interests was 10,131.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None
PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

   591

                                     PART I

ITEM 1.         BUSINESS

Parker & Parsley 86-A, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 10,131 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000 approximately 51% was attributable to sales made to Plains
Marketing, L.P. Pioneer USA is of the opinion that the loss of any one purchaser
would not have an adverse effect on its ability to sell its oil, natural gas
liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial

                                        2
   592

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.         PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 32
oil and gas wells. Five wells were sold and one well was abandoned. At December
31, 2000, 26 wells were producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.         LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.         SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.

                                       3
   593

                                     PART II

ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                DISTRIBUTIONS

At March 8, 2001, the Partnership had 10,131 outstanding limited partnership
interests held of record by 962 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $462,584 and
$154,204, respectively, were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                        2000             1999            1998             1997            1996
                                  ---------------  --------------- ---------------  --------------- ---------------
                                                                                      
Operating results:
-----------------
  Oil and gas sales                $    881,177     $    555,781     $   415,842     $   605,964     $    843,204
                                    ===========      ===========      ==========      ==========      ===========

  Gain on litigation
    settlement, net                $        -       $        -       $       -       $       -       $    290,690
                                    ===========      ===========      ==========      ==========      ===========

  Impairment of oil and gas
    properties                     $     12,800     $     28,052     $    23,593     $   496,887     $        -
                                    ===========      ===========      ==========      ==========      ===========

  Net income (loss)                $    487,574     $     96,423     $  (248,515)    $  (467,727)    $    741,771
                                    ===========      ===========      ==========      ==========      ===========

  Allocation of net income (loss):
    Managing general partner       $      4,876     $        964     $    (2,485)    $    (4,677)    $      7,417
                                    ===========      ===========      ==========      ==========      ===========

    Limited partners               $    482,698     $     95,459     $  (246,030)    $  (463,050)    $    734,354
                                    ===========      ===========      ==========      ==========      ===========

  Limited partners' net income
    (loss) per limited
    partnership interest           $      47.65     $       9.42     $    (24.28)    $    (45.71)    $      72.49
                                    ===========      ===========      ==========      ==========      ===========

  Limited partners' cash
    distributions per
    limited partnership
    interest                       $      45.66     $      15.22     $      9.42     $     27.44     $      94.54 (a)
                                    ===========      ===========      ==========      ==========      ===========

At year end:
-----------
  Identifiable assets              $    607,763     $    594,270     $   646,224     $ 1,000,424     $  1,804,366
                                    ===========      ===========      ==========      ==========      ===========


---------------

(a) Including litigation settlement per limited partnership interest of $28.41
in 1996.

                                       4
   594

ITEM 7.         MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 59% to $881,177 for 2000 as
compared to $555,781 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decrease in production. In 2000, 18,760
barrels of oil, 13,025 barrels of natural gas liquids ("NGLs") and 56,549 mcf of
gas were sold, or 41,210 barrel of oil equivalents ("BOEs"). In 1999, 18,743
barrels of oil, 14,483 barrels of NGLs and 62,354 mcf of gas were sold, or
43,618 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $11.87, or 70%, from
$17.00 in 1999 to $28.87 in 2000. The average price received per barrel of NGLs
increased $5.31, or 55%, from $9.63 in 1999 to $14.94 in 2000. The average price
received per mcf of gas increased 63% from $1.57 in 1999 to $2.56 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $31,944 was recognized during 2000 resulting
from equipment credits on two fully depleted wells.

Total costs and expenses decreased in 2000 to $432,464 as compared to $463,135
in 1999, a decrease of $30,671, or 7%. The decrease was due to declines in
depletion and the impairment of oil and gas properties, offset by increases in
production costs and general and administrative expense ("G&A").

Production costs were $364,985 in 2000 and $341,430 in 1999, resulting in an
increase of $23,555, or 7%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices, offset by a slight decline in
well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
73% from $16,673 in 1999 to $28,772 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $24,184 in 2000 and $9,436 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of

                                       5
   595

the Partnership's assets may have occurred. As a result of the review and
evaluation of its long- lived assets for impairment, the Partnership recognized
non-cash charges of $12,800 and $28,052 related to its oil and gas properties
during 2000 and 1999, respectively.

Depletion was $25,907 in 2000 as compared to $76,980 in 1999, representing a
decrease of $51,073, or 66%. This decrease was primarily due to a 40,953 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices and a reduction in the Partnership's net depletable basis from charges
taken in accordance with SFAS 121 during the fourth quarter of 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 34% to $555,781 from
$415,842 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production from 1998 to 1999. In 1999, 18,743
barrels of oil, 14,483 barrels of NGLs and 62,354 mcf of gas were sold, or
43,618 BOEs. In 1998, 20,308 barrels of oil, 11,164 barrels of NGLs and 49,805
mcf of gas were sold, or 39,773 BOEs.

The average price received per barrel of oil increased $3.68, or 28%, from
$13.32 in 1998 to $17.00 in 1999. The average price received per barrel of NGLs
increased $3.10, or 47%, from $6.53 in 1998 to $9.63 in 1999. The average price
received per mcf of gas increased 8% from $1.46 in 1998 to $1.57 in 1999.

Total costs and expenses decreased in 1999 to $463,135 as compared to $669,121
in 1998, a decrease of $205,986, or 31%. The decrease was due to declines in
depletion and production costs, offset by increases in the impairment of oil and
gas properties and G&A.

Production costs were $341,430 in 1999 and $372,460 in 1998, resulting in a
$31,030 decrease, or 8%. The decrease was due to declines in workover costs,
well maintenance costs and ad valorem taxes, offset by an increase in production
taxes due to an increase in oil and gas revenues.

During this period, G&A increased 34% from $12,476 in 1998 to $16,673 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $9,436 in
1999 and $9,062 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $28,052 and $23,593
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion was $76,980 in 1999 compared to $260,592 in 1998. This represented a
decrease of $183,612, or 70%. This decrease was the result of an increase in
proved reserves of 148,893 barrels of oil during 1999 due to higher commodity
prices and a reduction in the Partnership's net depletable basis from charges
taken in accordance with SFAS 121 during the fourth quarter of 1998.

                                       6
   596

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $229,299 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $328,536, offset by increases in production costs paid
of $23,555, G&A expenses paid of $12,099 and working capital of $63,583. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $364,711 to oil and gas receipts,
offset by a decrease of $36,175 resulting from a decrease in production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices, offset by a slight decline in
well maintenance costs. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were for
expenditures related to oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $31,944 received during 2000 were due to
equipment credits received on two fully depleted wells. Proceeds of $120 were
recognized in 1999 primarily from equipment credits received on active
properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $467,257, of which $4,673 was
distributed to the managing general partner and $462,584 to the limited
partners. In 1999, cash distributions to the partners were $155,762, of which
$1,558 was distributed to the managing general partner and $154,204 to the
limited partners.

                                       7
   597

ITEM 8.         FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS


                                                                                                            Page
                                                                                                            ----
                                                                                                            
Financial Statements of Parker & Parsley 86-A, Ltd:
  Independent Auditors' Report..........................................................................       10
  Balance Sheets as of December 31, 2000 and 1999.......................................................       11
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998.................................................................................       12
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998....................................................................       13
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998.................................................................................       14
  Notes to Financial Statements.........................................................................       15


                                       8
   598

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 86-A, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 86-A, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 86-A, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                                              Ernst & Young LLP

Dallas, Texas
March 9, 2001

                                       9
   599

                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                                                  2000                1999
                                                                           ----------------    ----------------
                                                                                           
                  ASSETS
                  ------

Current assets:
  Cash                                                                       $     46,169        $     76,838
  Accounts receivable - oil and gas sales                                         150,881              74,543
                                                                               ----------          ----------

         Total current assets                                                     197,050             151,381
                                                                               ----------          ----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                          7,132,242           7,125,711
Accumulated depletion                                                          (6,721,529)         (6,682,822)
                                                                               ----------          ----------

         Net oil and gas properties                                               410,713             442,889
                                                                               ----------          ----------

                                                                             $    607,763        $    594,270
                                                                              ===========         ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                               $     12,398        $     19,222

Partners' capital:
  Managing general partner                                                          4,647               4,444
  Limited partners (10,131 interests)                                             590,718             570,604
                                                                               ----------          ----------

                                                                                  595,365             575,048
                                                                               ----------          ----------

                                                                             $    607,763        $    594,270
                                                                              ===========         ===========


   The accompanying notes are an integral part of these financial statements.

                                       10
   600
                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                                 2000              1999             1998
                                                            ---------------   --------------   ---------------
                                                                                        
Revenues:
  Oil and gas                                                 $   881,177       $  555,781       $   415,842
  Interest                                                          6,917            3,777             4,764
  Gain on disposition of assets                                    31,944              -                 -
                                                                ---------         --------         ---------

                                                                  920,038          559,558           420,606
                                                                ---------         --------         ---------

Costs and expenses:
  Oil and gas production                                          364,985          341,430           372,460
  General and administrative                                       28,772           16,673            12,476
  Depletion                                                        25,907           76,980           260,592
  Impairment of oil and gas properties                             12,800           28,052            23,593
                                                                ---------         --------         ---------

                                                                  432,464          463,135           669,121
                                                                ---------         --------         ---------

Net income (loss)                                             $   487,574       $   96,423       $  (248,515)
                                                               ==========        =========        ==========

Allocation of net income (loss):
  Managing general partner                                    $     4,876       $      964       $    (2,485)
                                                               ==========        =========        ==========

  Limited partners                                            $   482,698       $   95,459       $  (246,030)
                                                               ==========        =========        ==========

Net income (loss) per limited partnership
  interest                                                    $     47.65       $     9.42       $    (24.28)
                                                               ==========        =========        ==========


   The accompanying notes are an integral part of these financial statements.

                                       11
   601
                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                               Managing
                                                                general           Limited
                                                                partner           partners           Total
                                                            ---------------    --------------   ---------------
                                                                                        
Partners' capital at January 1, 1998                         $     8,487        $   970,792      $   979,279

   Distributions                                                    (964)           (95,413)         (96,377)

   Net loss                                                       (2,485)          (246,030)        (248,515)
                                                               ---------          ---------        ---------

Partners' capital at December 31, 1998                             5,038            629,349          634,387

   Distributions                                                  (1,558)          (154,204)        (155,762)

   Net income                                                        964             95,459           96,423
                                                               ---------          ---------        ---------

Partners' capital at December 31, 1999                             4,444            570,604          575,048

   Distributions                                                  (4,673)          (462,584)        (467,257)

   Net income                                                      4,876            482,698          487,574
                                                               ---------          ---------        ---------

Partners' capital at December 31, 2000                       $     4,647        $   590,718      $   595,365
                                                              ==========         ==========       ==========


   The accompanying notes are an integral part of these financial statements.

                                       12
   602
                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                                  2000              1999             1998
                                                             --------------    --------------   --------------
                                                                                        
Cash flows from operating activities:
  Net income (loss)                                           $   487,574       $   96,423       $  (248,515)
  Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
       Impairment of oil and gas properties                        12,800           28,052            23,593
       Depletion                                                   25,907           76,980           260,592
       Gain on disposition of assets                              (31,944)             -                 -
  Changes in assets and liabilities:
       Accounts receivable                                        (76,338)         (26,964)           32,195
       Accounts payable                                            (6,824)           7,385            (9,308)
                                                                ---------         --------         ---------

         Net cash provided by operating activities                411,175          181,876            58,557
                                                                ---------         --------         ---------

Cash flows from investing activities:
  Additions to oil and gas properties                              (6,531)          (7,619)          (22,830)
  Proceeds from asset dispositions                                 31,944              120               -
                                                                ---------         --------         ---------

         Net cash provided by (used in)
            investing activities                                   25,413           (7,499)          (22,830)
                                                                ---------         --------         ---------

Cash flows used in financing activities:
  Cash distributions to partners                                 (467,257)        (155,762)          (96,377)
                                                                ---------         --------         ---------

Net increase (decrease) in cash                                   (30,669)          18,615           (60,650)
Cash at beginning of year                                          76,838           58,223           118,873
                                                                ---------         --------         ---------

Cash at end of year                                           $    46,169       $   76,838       $    58,223
                                                               ==========        =========        ==========


   The accompanying notes are an integral part of these financial statements.

                                       13
   603
                           PARKER & PARSLEY 86-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 86-A, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

                                       14
   604

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non- partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environ mental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $12,800, $28,052 and
$23,593 related to its proved oil and gas properties during 2000, 1999 and 1998,
respectively.

NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $695,197 less

                                       15
   605

than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                  2000             1999              1998
                                                             -------------    --------------    --------------
                                                                                        
   Net income (loss) per statements of operations             $   487,574      $    96,423       $  (248,515)
   Depletion and depreciation provisions for tax
     reporting purposes less than amounts for
     financial reporting purposes                                  16,131           66,147           251,615
   Impairment of oil and gas properties for financial
     reporting purposes                                            12,800           28,052            23,593
   Timing difference                                               67,848              -                 -
   Other, net                                                      (1,032)          (1,773)            2,118
                                                               ----------        ---------         ---------

         Net income per Federal income tax
           returns                                            $   583,321      $   188,849       $    28,811
                                                               ==========       ==========        ==========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                 2000              1999              1998
                                                            --------------    --------------    --------------
                                                                                        
       Development costs                                      $     6,531       $    7,619       $    22,830
                                                               ==========        =========        ==========


        Capitalized oil and gas properties consist of the following:



                                                                               2000                  1999
                                                                         ----------------      ----------------
                                                                                           
     Proved properties:
       Property acquisition costs                                          $    264,211          $    264,211
       Completed wells and equipment                                          6,868,031             6,861,500
                                                                             ----------            ----------

                                                                              7,132,242             7,125,711
     Accumulated depletion                                                   (6,721,529)           (6,682,822)
                                                                             ----------            ----------

                 Net oil and gas properties                                $    410,713          $    442,889
                                                                            ===========           ===========


                                       16
   606

NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                                 2000              1999             1998
                                                            --------------    --------------   --------------
                                                                                        
    Payment of lease operating and supervision
       charges in accordance with standard
       industry operating agreements                         $    167,350       $  167,820       $   161,913

    Reimbursement of general and administrative
       expenses                                              $     24,184       $    9,436       $     9,062


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA and the Partnership are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                              Pioneer
                                                                              USA (1)              Partnership
                                                                           -------------         ---------------
                                                                                              
   Revenues:
     Proceeds from disposition of depreciable properties                        9.09091%             90.90909%
       All other revenues                                                     24.242425%            75.757575%

   Costs and expenses:
     Lease acquisition costs, drilling and completion costs
       and all other costs                                                      9.09091%             90.90909%
     Operating costs, direct costs and general and
       administrative expenses                                                24.242425%            75.757575%


    (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
          at the Partnership level and 35 limited partner interests owned by
          Pioneer USA.

NOTE 7.          OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       17
   607



                                                                               Oil and NGLs              Gas
                                                                                  (bbls)                (mcf)
                                                                          --------------------  -------------------
                                                                                             
    Net proved reserves at January 1, 1998                                        315,662              469,065
    Revisions                                                                    (123,571)            (148,399)
    Production                                                                    (31,472)             (49,805)
                                                                               ----------           ----------

    Net proved reserves at December 31, 1998                                      160,619              270,861
    Revisions                                                                     273,095              545,216
    Production                                                                    (33,226)             (62,354)
                                                                               ----------           ----------

    Net proved reserves at December 31, 1999                                      400,488              753,723
    Revisions                                                                      83,992              171,142
    Production                                                                    (31,785)             (56,549)
                                                                               ----------           ----------

    Net proved reserves at December 31, 2000                                      452,695              868,316
                                                                               ==========           ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.60 per barrel of NGLs and $7.15 per mcf of gas,
discounted at 10% was approximately $3,610,000 and undiscounted was $7,252,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year- end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.

                                       18
   608



                                                                          For the years ended December 31,
                                                                 -------------------------------------------------
                                                                       2000             1999            1998
                                                                 ---------------- ---------------- ---------------
                                                                                   (in thousands)
                                                                                           
Oil and gas producing activities:
   Future cash inflows                                             $     15,459     $      9,741    $      1,763
   Future production costs                                               (8,207)          (5,896)         (1,433)
                                                                     ----------       ----------      ----------

                                                                          7,252            3,845             330
   10% annual discount factor                                            (3,642)          (1,727)            (89)
                                                                     ----------       ----------      ----------

   Standardized measure of discounted future net cash flows        $      3,610     $      2,118    $        241
                                                                    ===========      ===========     ===========




                                                                          For the years ended December 31,
                                                                 -------------------------------------------------
                                                                       2000             1999            1998
                                                                 ---------------- ---------------- ---------------
                                                                                   (in thousands)
                                                                                           
   Oil and Gas Producing Activities:
     Oil and gas sales, net of production costs                    $       (516)   $        (214)   $        (43)
     Net changes in prices and production costs                           1,408              829            (761)
     Revisions of previous quantity estimates                               753            1,942            (147)
     Accretion of discount                                                  212               24             113
     Changes in production rates, timing and other                         (365)            (704)            (51)
                                                                     ----------      -----------      ----------

     Change in present value of future net revenues                       1,492            1,877            (889)
                                                                     ----------      -----------      ----------

     Balance, beginning of year                                           2,118              241           1,130
                                                                     ----------      -----------      ----------

     Balance, end of year                                          $      3,610    $       2,118    $        241
                                                                    ===========     ============     ===========


NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                                2000              1999             1998
                                                              --------          --------         --------
                                                                                           
             Plains Marketing, L.P.                              51%               48%               -
             Genesis Crude Oil, L.P.                              -                 -               62%
             Western Gas Resources, Inc.                          7%                9%              29%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $31,479, which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

                                       19
   609

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Partnership affairs. As managing
        general partner and operator of the Partnership's properties, all
        production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $10,131,000. Pioneer USA is required to contribute amounts equal to 1%
        of initial Partnership capital less commission and offering expenses
        allocated to the limited partners and to contribute amounts necessary to
        pay costs and expenses allocated to it under the Partnership agreement
        to the extent its share of revenues does not cover such costs.

ITEM 9.         CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                AND FINANCIAL DISCLOSURE

None.

                                       20
   610

                                    PART III

ITEM 10.        DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                               Age at
                                            December 31,
        Name                                    2000                            Position
        ----                                    ----                            --------
                                                              
Scott D. Sheffield                               48                 President

Timothy L. Dove                                  45                 Executive Vice President, Chief
                                                                      Financial Officer and Director

Dennis E. Fagerstone                             51                 Executive Vice President and Director

Mark L. Withrow                                  53                 Executive Vice President, General
                                                                      Counsel and Director

Danny Kellum                                     46                 Executive Vice President - Domestic
                                                                      Operations and Director

Rich Dealy                                       34                 Vice President and Chief Accounting
                                                                      Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts

                                       21
   611

Institute of Technology in 1979 and received his M.B.A. in 1981 from the
University of Chicago. He became Executive Vice President - Business Development
of Pioneer and Pioneer USA in August 1997 and was also appointed a director of
Pioneer USA in August 1997. Mr. Dove assumed the position of Chief Financial
Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr. Dove joined
Parker & Parsley in May 1994 as Vice President - International and was promoted
to Senior Vice President - Business Development in October 1996, in which
position he served until August 1997. Prior to joining Parker & Parsley, Mr.
Dove was employed with Diamond Shamrock Corp., and its successor, Maxus Energy
Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.

                                       22
   612

ITEM 11.        EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.        SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)     Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 35 limited partner interests at January 1, 2001.

(b)     Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

                                       23
   613

ITEM 13.        CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                                 2000              1999             1998
                                                             -------------    -------------    -------------
                                                                                        
     Payment of lease operating and supervision
       charges in accordance with standard
       industry operating agreements                          $  167,350       $   167,820       $  161,913

     Reimbursement of general and administrative
       expenses                                               $   24,184       $     9,436       $    9,062


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.

                                       24
   614

                                     PART IV

ITEM 14.        EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.      Financial statements

              The following are filed as part of this Report:

                     Independent Auditors' Report

                     Balance sheets as of December 31, 2000 and 1999

                     Statements of operations for the years ended December 31,
                       2000, 1999 and 1998

                     Statements of partners' capital for the years ended
                        December 31, 2000, 1999 and 1998

                     Statements of cash flows for the years ended December 31,
                        2000, 1999 and 1998

                     Notes to financial statements

      2.      Financial statement schedules

              All financial statement schedules have been omitted since the
              required information is in the financial statements or notes
              thereto, or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.

                                       25
   615

                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                   PARKER & PARSLEY 86-A, LTD.

Dated: March 28, 2001              By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner


                                           By:     /s/ Scott D. Sheffield
                                                   -----------------------------
                                                   Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.


                                                                                         
/s/ Scott D. Sheffield                      President of Pioneer USA                           March 28, 2001
--------------------------------------
Scott D. Sheffield

/s/ Timothy L. Dove                         Executive Vice President, Chief                    March 28, 2001
--------------------------------------      Financial Officer and Director of
Timothy L. Dove                             Pioneer USA


/s/ Dennis E. Fagerstone                    Executive Vice President and                       March 28, 2001
--------------------------------------      Director of Pioneer USA
Dennis E. Fagerstone

/s/ Mark L. Withrow                         Executive Vice President, General                  March 28, 2001
--------------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow

/s/ Danny Kellum                            Executive Vice President - Domestic                March 28, 2001
--------------------------------------      Operations and Director of Pioneer
Danny Kellum                                USA

/s/ Rich Dealy                              Vice President and Chief Accounting                March 28, 2001
--------------------------------------      Officer of Pioneer USA
Rich Dealy


                                       26
   616

                           PARKER & PARSLEY 86-A, LTD.

                                INDEX TO EXHIBITS

        The following documents are incorporated by reference in response to
Item 14(c):



   Exhibit No.                                Description                                            Page
   -----------                                -----------                                            ----
                                                                                               
      3(a)                     Amended and Restated Certificate of                                    -
                               Limited Partnership of Parker & Parsley
                               86-A, Ltd. incorporated by reference to
                               Exhibit 3a of the Partnership's Registration
                               Statement on Form S-1 (Registration No.
                               33-3353) (hereinafter called the Partnership's
                               Registration Statement)

      4(a)                     Form of Agreement of Limited Partnership of                            -
                               Parker & Parsley 86-A, Ltd. incorporated by
                               reference to Exhibit A of Amendment No. 1 of
                               the Partnership's Registration Statement

      4(b)                     Form of Subscription Agreement incorporated by
                               reference to Exhibit C of Amendment No. 1 of
                               the Partnership's Registration Statement                               -

      4(b)                     Power of Attorney incorporated by reference to                         -
                               an Exhibit of the Partnership's Registration
                               Statement

      4(c)                     Specimen Certificate of Limited Partnership                            -
                               Interest incorporated by reference to Exhibit
                               4c of the Partnership's Registration Statement

     10(b)                     Development Program Agreement incorporated                             -
                               by reference to Exhibit B of Amendment No. 1
                               of the Partnership's Registration Statement



                                       27
   617




                           PARKER & PARSLEY 86-A, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                         Three months
                                             ended
                                           March 31,                             Years ended December 31,
                                      -------------------   --------------------------------------------------------------
                                       2001       2000         2000         1999         1998         1997         1996
                                      ------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                           
1996
Operating results:
  Oil and gas sales ...............   $        $  196,979   $  881,177   $  555,781   $  415,842   $  605,964   $  843,204
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
  settlement, net .................   $   --   $       --   $       --   $       --   $       --   $       --   $  290,690
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
      properties ..................   $        $       --   $   12,800   $   28,052   $   23,593   $  496,887   $       --
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss) ...............   $        $  105,432   $  487,574   $   96,423   $ (248,515)  $ (467,727)  $  741,771
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
      Managing general
        partner ...................   $        $    1,054   $    4,876   $      964   $   (2,485)  $   (4,677)  $    7,417
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners ............   $        $  104,378   $  482,698   $   95,459   $ (246,030)  $ (463,050)  $  734,354
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
      (loss) per limited
      partnership interest ........   $        $    10.30   $    47.65   $     9.42   $   (24.28)  $   (45.71)  $    72.49
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
      distributions per
      limited partnership
      interest ....................   $        $     8.66   $    45.66   $    15.22   $     9.42   $    27.44   $    94.54(a)
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets .............   $        $  613,701   $  607,763   $  594,270   $  646,224   $1,000,424   $1,804,366
                                      ======   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $28.41
     in 1996.



   618

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 86-B, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
86-B, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 86-B, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   619

                           PARKER & PARSLEY 86-B, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $  17,208

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $  27,115

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   3,829
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  224.17

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.60 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001 (c)                                                    $  123.77

        --        as of December 31, 2000 (c)                                                 $  128.81

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  208.10

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  217.61

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     235
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2036, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                      -2-

   620

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 33-3353B


                           PARKER & PARSLEY 86-B, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                              75-2140235
          ----------------------------------        ---------------------
           (State or other jurisdiction of             (I.R.S. Employer
           incorporation or organization)           Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]






   621



                           PARKER & PARSLEY 86-B, LTD.

                                TABLE OF CONTENTS



                                                                        Page

                                                                      
                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000......................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000...........................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000...........................    6

           Notes to Financial Statements.............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K..........................   10

           Signatures................................................   11



                                        2

   622



                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,         December 31,
                                                       2001                2000
                                                    ------------       ------------
                                                    (Unaudited)
                       ASSETS

                                                                 
Current assets:
  Cash                                              $    194,492       $    220,466
  Accounts receivable - oil and gas sales                226,248            260,049
                                                    ------------       ------------
          Total current assets                           420,740            480,515
                                                    ------------       ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                11,812,974         11,805,173
Accumulated depletion                                (10,062,419)       (10,032,733)
                                                    ------------       ------------
          Net oil and gas properties                   1,750,555          1,772,440
                                                    ------------       ------------
                                                    $  2,171,295       $  2,252,955
                                                    ============       ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $     21,289       $     15,305

Partners' capital:
  Managing general partner                                20,223             21,100
  Limited partners (17,208 interests)                  2,129,783          2,216,550
                                                    ------------       ------------
                                                       2,150,006          2,237,650
                                                    ------------       ------------
                                                    $  2,171,295       $  2,252,955
                                                    ============       ============





  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   623



                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)






                                                     Three months ended
                                                         March 31,
                                                 --------------------------
                                                    2001            2000
                                                 ----------      ----------

                                                           
Revenues:
  Oil and gas                                    $  438,473      $  402,132
  Interest                                            3,661           3,072
  Gain on disposition of assets                          --           1,419
                                                 ----------      ----------
                                                    442,134         406,623
                                                 ----------      ----------
Costs and expenses:
  Oil and gas production                            168,451         169,111
  General and administrative                         13,154          12,064
  Depletion                                          29,686          33,998
                                                 ----------      ----------
                                                    211,291         215,173
                                                 ----------      ----------
Net income                                       $  230,843      $  191,450
                                                 ==========      ==========
Allocation of net income:
  Managing general partner                       $    2,308      $    1,915
                                                 ==========      ==========
  Limited partners                               $  228,535      $  189,535
                                                 ==========      ==========
Net income per limited partnership interest      $    13.28      $    11.01
                                                 ==========      ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   624



                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                      Managing
                                      general       Limited
                                      partner       partners        Total
                                    -----------    ----------     ----------

                                                         
Balance at January 1, 2001          $   21,100     $2,216,550     $2,237,650

   Distributions                        (3,185)      (315,302)      (318,487)

   Net income                            2,308        228,535        230,843
                                    ----------     ----------     ----------

Balance at March 31, 2001           $   20,223     $2,129,783     $2,150,006
                                    ==========     ==========     ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        5

   625



                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                               Three months ended
                                                                    March 31,
                                                         -------------------------------
                                                             2001               2000
                                                         ------------       ------------

                                                                      
Cash flows from operating activities:
  Net income                                             $    230,843       $    191,450
  Adjustments to reconcile net income to net cash
    provided by operating activities:
       Depletion                                               29,686             33,998
       Gain on disposition of assets                               --             (1,419)
  Changes in assets and liabilities:
    Accounts receivable                                        33,801            (25,986)
    Accounts payable                                            5,984              6,730
                                                         ------------       ------------
          Net cash provided by operating activities           300,314            204,773
                                                         ------------       ------------
Cash flows from investing activities:
  Additions to oil and gas properties                          (7,801)              (826)
  Proceeds from disposition of assets                              --              1,419
                                                         ------------       ------------
          Net cash provided by (used in) investing
            activities                                         (7,801)               593
                                                         ------------       ------------
Cash flows used in financing activities:
  Cash distributions to partners                             (318,487)          (180,685)
                                                         ------------       ------------
Net increase (decrease) in cash                               (25,974)            24,681
Cash at beginning of period                                   220,466            206,408
                                                         ------------       ------------
Cash at end of period                                    $    194,492       $    231,089
                                                         ============       ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   626



                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley 86-B, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 9% to $438,473 for the three
months ended March 31, 2001 as compared to $402,132 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 8,976
barrels of oil, 2,760 barrels of natural gas liquids ("NGLs") and 20,049 mcf of
gas were sold, or 15,078 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 10,821 barrels of oil, 5,059 barrels of NGLs and


                                        7

   627



20,435 mcf of gas were sold, or 19,286 BOEs. Of the decrease, 1,732 BOEs are
attributable to two wells reaching payout pursuant to the terms of the farmout
agreements which reduced the Partnership's net revenue interest in the wells.

The average price received per barrel of oil increased $1.35, or 5%, from $27.60
for the three months ended March 31, 2000 to $28.95 for the same period in 2001.
The average price received per barrel of NGLs increased $5.78, or 43%, from
$13.37 for the three months ended March 31, 2000 to $19.15 for the same period
in 2001. The average price received per mcf of gas increased 256% from $1.76
during the three months ended March 31, 2000 to $6.27 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $1,419 was recognized during the three months
ended March 31, 2000 due to equipment credits received on one fully depleted
well.

Costs and Expenses:

Total costs and expenses decreased to $211,291 for the three months ended March
31, 2001 as compared to $215,173 for the same period in 2000, a decrease of
$3,882, or 2%. This decrease was primarily due to declines in depletion and
production costs, offset by an increase in general and administrative expenses
("G&A").

Production costs were $168,451 for the three months ended March 31, 2001
compared to $169,111 for the same period in 2000, a decrease of $660. The
decrease was primarily due to a decline in lease operating and production taxes
attributable to the wells that reached payout pursuant to the terms of the
farmout agreements as noted above, offset by an increase in production taxes
associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 9% from $12,064 for the three months ended March 31, 2000 to $13,154
for the same period in 2001, primarily due to an increase in the accrual of tax
preparation fees.

Depletion was $29,686 for the three months ended March 31, 2001 compared to
$33,998 for the same period in 2000, a decrease of $4,312, or 13%. This decrease
was primarily due to a decrease in oil production of 1,845 barrels for the three
months ended March 31, 2001 compared to the same period in 2000 and a reduction
in the Partnership's net depletable basis from charges taken in accordance with
Statement of Financial Accounting Standards No. 121, "Accounting for the
Impairment of Long-Lived Assets and for Long-Lived Assets to be Disposed Of"
("SFAS 121") during the fourth quarter of 2000.


                                        8

   628



Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $95,541 for the three months
ended March 31, 2001 from the same period in 2000. This increase was primarily
attributable to an increase of $36,930 in oil and gas sales receipts and
reductions in production costs of $660 and working capital of $59,041, offset by
an increase in G&A expenses of $1,090. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $136,786 to oil and gas receipts, offset by $99,856 resulting from
the decline in production during 2001 as compared to the same period in 2000.
The decrease in production costs was primarily due to lower well maintenance
costs, offset by an increase in production taxes associated with higher oil and
gas prices. The increase in G&A was primarily due to an increase in the accrual
of tax preparation fees.

Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during the three months ended March 31,
2001 and 2000 were related to expenditures for oil and gas equipment upgrades on
active properties.

Proceeds from disposition of assets of $1,419 recognized during the three months
ended March 31, 2000 were due to equipment credits received on one fully
depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $318,487, of which $3,185 was distributed to the managing general partner
and $315,302 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $180,685, of which $1,807 was
distributed to the managing general partner and $178,878 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

                                        9

   629



----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K -none.


                                       10

   630


                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                     PARKER & PARSLEY 86-B, LTD.


                                 By:      Pioneer Natural Resources USA, Inc.
                                           Managing General Partner



Dated:  May 9, 2001              By:      /s/ Rich Dealy
                                          ----------------------------------
                                          Rich Dealy, Vice President
                                            and Chief Accounting Officer


                                       11



   631

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 33-3353B


                           PARKER & PARSLEY 86-B, LTD.
             (Exact name of Registrant as specified in its charter)



                             TEXAS                                                                   75-2140235
          -----------------------------------------                                          --------------------------
                                                                                          
          (State or other jurisdiction of                                                       (I.R.S. Employer
          incorporation or organization)                                                     Identification Number)

1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                                      75039
----------------------------------------------------------------                                  -------------
             (Address of principal executive offices)                                               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$17,080,000.

             As of March 8, 2001, the number of outstanding limited
                       partnership interests was 17,208.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None
PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

   632

                                     PART I

ITEM 1.         BUSINESS

Parker & Parsley 86-B, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 17,208 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 36% and 16% were attributable to sales
made to Plains Marketing, L.P. and Mobil Oil Corporation, respectively. Pioneer
USA is of the opinion that the loss of any one purchaser would not have an
adverse effect on its ability to sell its oil, natural gas liquids ("NGLs") and
gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial

                                        2
   633

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.         PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 56
oil and gas wells. At December 31, 2000, 43 wells were producing. Nine wells and
interests in two abandoned wells were sold and two wells were plugged and
abandoned.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.         LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.         SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.

                                        3
   634

                                     PART II

ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                DISTRIBUTIONS

At March 8, 2001, the Partnership had 17,208 outstanding limited partnership
interests held of record by 1,409 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $923,558 and
$357,887, respectively, were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                        2000            1999             1998            1997            1996
                                  --------------- ---------------  --------------- --------------- ---------------
                                                                                      
Operating results:
-----------------
  Oil and gas sales                 $ 1,756,242     $  1,056,533     $   928,899     $  1,369,807    $  1,700,251
                                     ==========      ===========      ==========      ===========     ===========

  Gain on litigation
     settlement, net                $       -       $        -       $       -       $        -      $    565,756
                                     ==========      ===========      ==========      ===========     ===========

  Impairment of oil and gas
     properties                     $    13,279     $       -        $   509,585     $    561,432    $      4,960
                                     ==========      ===========      ==========      ===========     ===========

  Net income (loss)                 $   933,292     $    246,008     $  (807,041)    $   (158,796)   $  1,229,639
                                     ==========      ===========      ==========      ===========     ===========

  Allocation of net income
    (loss):
     Managing general partner       $     9,333     $      2,460     $    (8,070)    $     (1,587)   $     12,296
                                     ==========      ===========      ==========      ===========     ===========

      Limited partners              $   923,959     $    243,548     $  (798,971)    $   (157,209)   $  1,217,343
                                     ==========      ===========      ==========      ===========     ===========

  Limited partners' net
     income (loss) per limited
     partnership interest           $     53.69     $      14.15     $    (46.43)    $      (9.14)   $      70.74
                                     ==========      ===========      ==========      ===========     ===========

  Limited partners' cash
     distributions per limited
     partnership interest           $     53.67     $      20.80     $     18.70     $      46.77    $      86.49 (a)
                                     ==========      ===========      ==========      ===========     ===========

At year end:
-----------
  Identifiable assets               $ 2,252,955     $  2,266,438     $ 2,363,955     $  3,520,172    $  4,548,338
                                     ==========      ===========      ==========      ===========     ===========


---------------

(a) Including litigation settlement per limited partnership interest of $32.55
in 1996.

                                        4
   635

ITEM 7.         MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 66% to $1,756,242 for 2000 as
compared to $1,056,533 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 41,276
barrels of oil, 21,061 barrels of natural gas liquids ("NGLs") and 79,859 mcf of
gas were sold, or 75,647 barrel of oil equivalents ("BOEs"). In 1999, 40,490
barrels of oil, 22,642 barrels of NGLs and 86,726 mcf of gas were sold, or
77,586 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.27, or 71%, from
$17.18 in 1999 to $29.45 in 2000. The average price received per barrel of NGLs
increased $5.61, or 60%, from $9.39 in 1999 to $15.00 in 2000. The average price
received per mcf of gas increased 65% from $1.71 in 1999 to $2.82 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $21,074 was received during 2000 due to the
sale of equipment on one plugged and abandoned well. Abandoned property costs of
$12,161 were also incurred during 2000 to plug and abandon this well.

Total costs and expenses increased in 2000 to $861,600 as compared to $821,102
in 1999, an increase of $40,498, or 5%. The increase was due to increases in
production costs, general and administrative expenses ("G&A"), the impairment of
oil and gas properties and abandoned property costs, offset by a decline in
depletion.

Production costs were $670,780 in 2000 and $611,991 in 1999, resulting in an
increase of $58,789, or 10%. This increase was primarily due to higher
production taxes associated with higher oil and gas prices and additional well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
66% from $31,696 in 1999 to $52,687 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $44,975 in 2000 and $19,909 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated

                                       5
   636

to reflect changes in Pioneer USA's overall business activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $13,279 related to its oil and gas properties during 2000.

Depletion was $112,693 in 2000 as compared to $177,415 in 1999, representing a
decrease of $64,722, or 36%. This decrease was primarily due to a 65,045 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 14% to $1,056,533 from
$928,899 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 40,490 barrels of oil,
22,642 barrels of NGLs and 86,726 mcf of gas were sold, or 77,586 BOEs. In 1998,
47,107 barrels of oil, 23,292 barrels of NGLs and 97,715 mcf of gas were sold,
or 86,685 BOEs.

The average price received per barrel of oil increased $4.10, or 31%, from
$13.08 in 1998 to $17.18 in 1999. The average price received per barrel of NGLs
increased $2.59, or 38%, from $6.80 in 1998 to $9.39 in 1999. The average price
received per mcf of gas increased 8% from $1.58 in 1998 to $1.71 in 1999.

A gain on disposition of assets of $6,371 was recognized during 1998 from the
sale of equipment on one well plugged and abandoned during 1998. Abandoned
property costs of $20,389 were also incurred during 1998 to plug and abandon
this well.

Total costs and expenses decreased in 1999 to $821,102 as compared to $1,755,278
in 1998, a decrease of $934,176, or 53%. The decrease was due to declines in the
impairment of oil and gas properties, depletion, production costs and abandoned
property costs, offset by an increase in G&A.

Production costs were $611,991 in 1999 and $662,691 in 1998, resulting in a
$50,700 decrease, or 8%. This decrease was due to lower well maintenance costs
and ad valorem taxes, offset by an increase in workover costs incurred to
stimulate well production.

During this period, G&A increased 14% from $27,867 in 1998 to $31,696 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $19,909 in
1999 and $21,984 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $509,585 related to its
oil and gas properties during 1998.

                                       6
   637

Depletion was $177,415 in 1999 compared to $534,746 in 1998. This represented a
decrease of $357,331, or 67%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 343,529 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 6,617
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $561,909 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $706,708, offset by increases in production costs paid
of $58,789, G&A expenses paid of $20,991, abandoned costs paid of $12,161 and
working capital of $52,858. The increase in oil and gas receipts resulted from
the increase in commodity prices during 2000 which contributed an additional
$726,611 to oil and gas receipts, offset by $19,903 resulting from the decline
in production during 2000. The increase in production costs was primarily due to
increased production taxes associated with higher oil and gas prices and well
maintenance costs incurred to stimulate well production. The increase in G&A was
primarily due to higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for oil and gas equipment upgrades on active properties.

Proceeds from disposition of assets of $23,670 was recognized during 2000. The
gain was comprised of $21,074 received from the sale of equipment on one well
plugged and abandoned during the current period and $2,596 from equipment
credits received on one active well. Proceeds of $8,980 in 1999 were from
equipment credits received on active properties.

                                       7
   638

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $932,887, of which $9,329 was
distributed to the managing general partner and $923,558 to the limited
partners. In 1999, cash distributions to the partners were $361,502, of which
$3,615 was distributed to the managing general partner and $357,887 to the
limited partners.

                                       8
   639

ITEM 8.         FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                                            Page
                                                                                                            ----
                                                                                                            
Financial Statements of Parker & Parsley 86-B, Ltd:
  Independent Auditors' Report..........................................................................       10
  Balance Sheets as of December 31, 2000 and 1999.......................................................       11
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998.................................................................................       12
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998....................................................................       13
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998.................................................................................       14
  Notes to Financial Statements.........................................................................       15


                                       9
   640

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 86-B, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 86-B, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 86-B, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                              Ernst & Young LLP


Dallas, Texas
March 9, 2001

                                       10
   641

                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                                                  2000                1999
                                                                           ------------------  ------------------
                                                                                           
                 ASSETS
                 ------

Current assets:
  Cash                                                                       $      220,466      $     206,408
  Accounts receivable - oil and gas sales                                           260,049            179,740
                                                                               ------------        -----------

          Total current assets                                                      480,515            386,148
                                                                               ------------        -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                           11,805,173         12,044,833
Accumulated depletion                                                           (10,032,733)       (10,164,543)
                                                                               ------------        -----------

          Net oil and gas properties                                              1,772,440          1,880,290
                                                                               ------------        -----------

                                                                             $    2,252,955      $   2,266,438
                                                                              =============       ============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                               $       15,305      $      29,193

Partners' capital:
  Managing general partner                                                           21,100             21,096
  Limited partners (17,208 interests)                                             2,216,550          2,216,149
                                                                               ------------        -----------

                                                                                  2,237,650          2,237,245
                                                                               ------------        -----------

                                                                             $    2,252,955      $   2,266,438
                                                                              =============       ============


   The accompanying notes are an integral part of these financial statements.

                                       11
   642
                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                                  2000              1999             1998
                                                            ----------------  ---------------- ----------------
                                                                                        
Revenues:
  Oil and gas                                                 $  1,756,242     $   1,056,533     $    928,899
  Interest                                                          17,576            10,577           12,967
  Gain on disposition of assets                                     21,074               -              6,371
                                                                ----------       -----------       ----------

                                                                 1,794,892         1,067,110          948,237
                                                                ----------       -----------       ----------

Costs and expenses:
  Oil and gas production                                           670,780           611,991          662,691
  General and administrative                                        52,687            31,696           27,867
  Impairment of oil and gas properties                              13,279               -            509,585
  Depletion                                                        112,693           177,415          534,746
  Abandoned property                                                12,161               -             20,389
                                                                ----------       -----------       ----------

                                                                   861,600           821,102        1,755,278
                                                                ----------       -----------       ----------

Net income (loss)                                             $    933,292     $     246,008     $   (807,041)
                                                               ===========      ============      ===========

Allocation of net income (loss):
  Managing general partner                                    $      9,333     $       2,460     $     (8,070)
                                                               ===========      ============      ===========

  Limited partners                                            $    923,959     $     243,548     $   (798,971)
                                                               ===========      ============      ===========

Net income (loss) per limited partnership interest            $      53.69     $       14.15     $     (46.43)
                                                               ===========      ============      ===========


   The accompanying notes are an integral part of these financial statements.

                                       12
   643
                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                           Managing
                                                           general              Limited
                                                           partner              partners               Total
                                                      ---------------       ---------------      ----------------
                                                                                          
Partners' capital at January 1, 1998                   $     33,572          $  3,451,264          $  3,484,836

   Distributions                                             (3,251)             (321,805)             (325,056)

   Net loss                                                  (8,070)             (798,971)             (807,041)
                                                         ----------            ----------            ----------

Partners' capital at December 31, 1998                       22,251             2,330,488             2,352,739

   Distributions                                             (3,615)             (357,887)             (361,502)

   Net income                                                 2,460               243,548               246,008
                                                         ----------            ----------            ----------

Partners' capital at December 31, 1999                       21,096             2,216,149             2,237,245

   Distributions                                             (9,329)             (923,558)             (932,887)

   Net income                                                 9,333               923,959               933,292
                                                         ----------            ----------            ----------

Partners' capital at December 31, 2000                 $     21,100          $  2,216,550          $  2,237,650
                                                        ===========           ===========           ===========


   The accompanying notes are an integral part of these financial statements.

                                       13
   644
                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                                  2000              1999             1998
                                                             --------------    --------------   --------------
                                                                                        
Cash flows from operating activities:
  Net income (loss)                                           $   933,292       $  246,008       $  (807,041)
  Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
       Impairment of oil and gas properties                        13,279              -             509,585
       Depletion                                                  112,693          177,415           534,746
       Gain on disposition of assets                              (21,074)             -              (6,371)
     Changes in assets and liabilities:
       Accounts receivable                                        (80,309)         (59,316)           47,751
       Accounts payable                                           (13,888)          17,977           (24,120)
                                                                ---------         --------         ---------

          Net cash provided by operating activities               943,993          382,084           254,550
                                                                ---------         --------         ---------

Cash flows from investing activities:
  Additions to oil and gas properties                             (20,718)          (8,474)          (19,495)
  Proceeds from disposition of assets                              23,670            8,980            15,526
                                                                ---------         --------         ---------

          Net cash provided by (used in)
            investing activities                                    2,952              506            (3,969)
                                                                ---------         --------         ---------

Cash flows used in financing activities:
  Cash distributions to partners                                 (932,887)        (361,502)         (325,056)
                                                                ---------         --------         ---------

Net  increase (decrease) in cash                                   14,058           21,088           (74,475)
Cash at beginning of year                                         206,408          185,320           259,795
                                                                ---------         --------         ---------

Cash at end of year                                           $   220,466       $  206,408       $   185,320
                                                               ==========        =========        ==========


   The accompanying notes are an integral part of these financial statements.

                                       14
   645
                           PARKER & PARSLEY 86-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 86-B, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the

                                       15
   646

respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non- partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $13,279 and $509,585
related to its proved oil and gas properties during 2000 and 1998, respectively.

                                       16
   647

NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $38,785 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                  2000             1999             1998
                                                             --------------   --------------   --------------
                                                                                        
  Net income (loss) per statements of operations              $   933,292      $   246,008       $  (807,041)
  Depletion and depreciation provisions for tax
    reporting purposes less than amounts for
    financial reporting purposes                                  104,139          168,298           525,430
  Impairment of oil and gas properties for financial
    reporting purposes                                             13,279              -             509,585
  Intangible development costs capitalized for
    financial reporting purposes and expensed
    for tax reporting purposes                                    (13,305)             -                 -
  Other, net                                                         (142)          11,789             6,831
                                                                ---------        ---------         ---------

         Net income per Federal income tax
           returns                                            $ 1,037,263      $   426,095       $   234,805
                                                               ==========       ==========        ==========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                 2000              1999              1998
                                                            --------------    --------------    --------------
                                                                                        
       Development costs                                     $     20,718       $     8,474      $    19,495
                                                              ===========        ==========       ==========


        Capitalized oil and gas properties consist of the following:



                                                                                2000                  1999
                                                                         ------------------    ------------------
                                                                                           
     Proved properties:
       Property acquisition costs                                          $      439,613        $      444,922
       Completed wells and equipment                                           11,365,560            11,599,911
                                                                             ------------          ------------

                                                                               11,805,173            12,044,833
     Accumulated depletion                                                    (10,032,733)          (10,164,543)
                                                                             ------------          ------------

             Net oil and gas properties                                    $    1,772,440        $    1,880,290
                                                                            =============         =============


NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:

                                       17
   648



                                                                 2000             1999              1998
                                                            --------------   --------------    --------------
                                                                                        
     Payment of lease operating and supervision
       charges in accordance with standard
       industry operating agreements                         $    298,127      $   298,479       $   296,383

     Reimbursement of general and administrative
       expenses                                              $     44,975      $    19,909       $    21,984


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA and the Partnership are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                             Pioneer
                                                                             USA (1)               Partnership
                                                                         --------------          ---------------
                                                                                             
     Revenues:
       Proceeds from disposition of depreciable properties                   9.09091%              90.90909%
       All other revenues                                                   24.242425%             75.757575%
     Costs and expenses:
       Lease acquisition costs, drilling and completion costs
          and all other costs                                                9.09091%              90.90909%
       Operating costs, direct costs and general and
          administrative expenses                                           24.242425%             75.757575%


    (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
          at the Partnership level and 128 limited partner interests owned by
          Pioneer USA.

NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       18
   649



                                                                              Oil and NGLs             Gas
                                                                                  (bbls)              (mcf)
                                                                          --------------------  -------------------
                                                                                              
     Net proved reserves at January 1, 1998                                       940,047            1,239,206
     Revisions                                                                   (401,595)            (457,837)
     Production                                                                   (70,399)             (97,715)
                                                                              -----------           ----------

     Net proved reserves at December 31, 1998                                     468,053              683,654
     Revisions                                                                    550,528              841,323
     Production                                                                   (63,132)             (86,726)
                                                                              -----------           ----------

     Net proved reserves at December 31, 1999                                     955,449            1,438,251
     Revisions                                                                     42,519             (145,295)
     Production                                                                   (62,337)             (79,859)
                                                                              -----------           ----------

     Net proved reserves at December 31, 2000                                     935,631            1,213,097
                                                                              ===========           ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.61 per barrel of NGLs and $7.82 per mcf of gas,
discounted at 10% was approximately $7,100,000 and undiscounted was $14,263,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.

                                       19
   650



                                                                          For the years ended December 31,
                                                                 -------------------------------------------------
                                                                       2000             1999            1998
                                                                 ---------------- ---------------- ---------------
                                                                                   (in thousands)
                                                                                           
Oil and gas producing activities:
   Future cash inflows                                             $     30,354     $     23,606    $      5,045
   Future production costs                                              (16,091)         (13,697)         (3,839)
                                                                     ----------       ----------      ----------

                                                                         14,263            9,909           1,206
   10% annual discount factor                                            (7,163)          (4,671)           (387)
                                                                     ----------       ----------      ----------

   Standardized measure of discounted future net cash flows        $      7,100     $      5,238    $        819
                                                                    ===========      ===========     ===========




                                                                          For the years ended December 31,
                                                                 -------------------------------------------------
                                                                       2000             1999            1998
                                                                 ---------------- ---------------- ---------------
                                                                                   (in thousands)
                                                                                           
   Oil and Gas Producing Activities:
     Oil and gas sales, net of production costs                    $     (1,085)   $        (445)   $       (266)
     Net changes in prices and production costs                           2,757            2,398          (2,377)
     Revisions of previous quantity estimates                               121            3,891            (547)
     Accretion of discount                                                  524               82             377
     Changes in production rates, timing and other                         (455)          (1,507)           (140)
                                                                     ----------      -----------      ----------

     Change in present value of future net revenues                       1,862            4,419          (2,953)
                                                                     ----------      -----------      ----------

     Balance, beginning of year                                           5,238              819           3,772
                                                                     ----------      -----------      ----------

     Balance, end of year                                          $      7,100    $       5,238    $        819
                                                                    ===========     ============     ===========


NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                                2000              1999              1998
                                                              --------          --------          --------
                                                                                            
             Plains Marketing, L.P.                              36%               35%                -
             Genesis Crude Oil, L.P.                              -                 -                41%
             Western Gas Resources, Inc.                          2%                4%               17%
             Mobil Oil Corporation                               16%               15%               15%
             Texaco Trading & Transportation                      4%                8%               10%


        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and Mobil Oil Corporation were $54,631 and $21,954, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating

                                       20
   651

        and general and administrative expenses. In return, it is allocated 1%
        of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $17,208,000. Pioneer USA is required to contribute amounts equal to 1%
        of initial Partnership capital less commission and offering expenses
        allocated to the limited partners and to contribute amounts necessary to
        pay costs and expenses allocated to it under the Partnership agreement
        to the extent its share of revenues does not cover such costs.

ITEM 9.         CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                AND FINANCIAL DISCLOSURE

None.

                                       21
   652

                                    PART III

ITEM 10.        DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                               Age at
                                            December 31,
        Name                                    2000                            Position
        ----                                    ----                            --------
                                                              
Scott D. Sheffield                               48                 President

Timothy L. Dove                                  44                 Executive Vice President, Chief
                                                                      Financial Officer and Director

Dennis E. Fagerstone                             51                 Executive Vice President and Director

Mark L. Withrow                                  53                 Executive Vice President, General
                                                                      Counsel and Director

Danny Kellum                                     46                 Executive Vice President - Domestic
                                                                      Operations and Director

Rich Dealy                                       34                 Vice President and Chief Accounting
                                                                      Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

                                       22
   653

        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.

                                       23
   654

ITEM 11.        EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Note 6 and 9 of Notes to Financial Statements included in "Item 8. Financial
Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.        SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)     Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 128 limited partner interests at January 1, 2001.

(b)     Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.        CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:

                                       24
   655



                                                                 2000              1999              1998
                                                            -------------     -------------     -------------
                                                                                        
  Payment of lease operating and supervision
     charges in accordance with standard
     industry operating agreements                            $  298,127       $   298,479       $   296,383

  Reimbursement of general and administrative
     expenses                                                 $   44,975       $    19,909       $    21,984


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.

                                       25
   656

                                     PART IV

ITEM 14.        EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)    1.    Financial statements

             The following are filed as part of this Report:

                     Independent Auditors' Report

                     Balance sheets as of December 31, 2000 and 1999

                     Statements of operations for the years ended December 31,
                       2000, 1999 and 1998

                     Statements of partners' capital for the years ended
                       December 31, 2000, 1999 and 1998

                     Statements of cash flows for the years ended December 31,
                       2000, 1999 and 1998

                     Notes to financial statements

       2.    Financial statement schedules

             All financial statement schedules have been omitted since the
             required information is in the financial statements or notes
             thereto, or is not applicable nor required.

(b)    Reports on Form 8-K

None.

(c)    Exhibits

       The exhibits listed on the accompanying index to exhibits are filed or
       incorporated by reference as part of this Report.

                                       26
   657

                               S I G N A T U R E S

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                  PARKER & PARSLEY 86-B, LTD.

Dated: March 29, 2001             By:     Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:     /s/ Scott D. Sheffield
                                                  ------------------------------
                                                  Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.


                                                                                         
/s/ Scott D. Sheffield                       President of Pioneer USA                          March 29, 2001
--------------------------------------
Scott D. Sheffield

/s/ Timothy L. Dove                          Executive Vice President, Chief                   March 29, 2001
--------------------------------------       Financial Officer and Director of
Timothy L. Dove                              Pioneer USA

/s/ Dennis E. Fagerstone                     Executive Vice President and                      March 29, 2001
--------------------------------------       Director of Pioneer USA
Dennis E. Fagerstone

/s/ Mark L. Withrow                          Executive Vice President, General                 March 29, 2001
--------------------------------------       Counsel and Director of Pioneer USA
Mark L. Withrow

/s/ Danny Kellum                             Executive Vice President - Domestic               March 29, 2001
--------------------------------------       Operations and Director of Pioneer
Danny Kellum                                 USA

/s/ Rich Dealy                               Vice President and Chief Accounting               March 29, 2001
--------------------------------------       Officer of Pioneer USA
Rich Dealy


                                       27
   658

                           PARKER & PARSLEY 86-B, LTD.

                                INDEX TO EXHIBITS

        The following documents are incorporated by reference in response to
Item 14(c):



   Exhibit No.                                  Description                                         Page
   -----------                                  -----------                                         ----
                                                                                              
     3(a)                       Amended and Restated Certificate of                                   -
                                Limited Partnership of Parker & Parsley
                                86-B, Ltd. incorporated by reference to
                                Exhibit 3a of the Partnership's Registration
                                Statement on Form S-1 (Registration No.
                                33-3353) (hereinafter called the Partnership's
                                Registration Statement)

     4(a)                       Form of Agreement of Limited Partnership of                           -
                                Parker & Parsley 86-B, Ltd. incorporated by
                                reference to Exhibit A of Amendment No. 1 of
                                the Partnership's Registration Statement

     4(b)                       Form of Subscription Agreement incorporated by
                                reference to Exhibit C of Amendment No. 1 of
                                the Partnership's Registration Statement                              -

     4(b)                       Power of Attorney incorporated by reference to                        -
                                an Exhibit of the Partnership's Registration
                                Statement

     4(c)                       Specimen Certificate of Limited Partnership                           -
                                Interest incorporated by reference to Exhibit
                                4c of the Partnership's Registration Statement

    10(b)                       Development Program Agreement incorporated                            -
                                by reference to Exhibit B of Amendment No. 1
                                of the Partnership's Registration Statement



                                       28
   659



                           PARKER & PARSLEY 86-B, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  402,132   $1,756,242   $1,056,533   $  928,899   $1,369,807   $1,700,251
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $     --   $       --   $       --   $       --   $       --   $       --   $  565,756
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
      properties                   $          $       --   $   13,279   $       --   $  509,585   $  561,432   $    4,960
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  191,450   $  933,292   $  246,008   $ (807,041)  $ (158,796)  $1,229,639
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
        partner                    $          $    1,915   $    9,333   $    2,460   $   (8,070)  $   (1,587)  $   12,296
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  189,535   $  923,959   $  243,548   $ (798,971)  $ (157,209)  $1,217,343
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
      income (loss) per limited
      partnership interest         $          $    11.01   $    53.69   $    14.15   $   (46.43)  $    (9.14)  $    70.74
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
      distributions per limited
      partnership interest         $          $    10.40   $    53.67   $    20.80   $    18.70   $    46.77   $    86.49(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $2,283,933   $2,252,955   $2,266,438   $2,363,955   $3,520,172   $4,548,338
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $32.55
     in 1996.



   660
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 86-C, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED        , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS        , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
86-C, Ltd. and supplements the proxy statement/prospectus dated         , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc.,
by which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 86-C, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                       -1-
   661

                           PARKER & PARSLEY 86-C, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                             
Aggregate Initial Investment by the Limited Partners(a)                                         $   19,317

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                     $   28,723

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding
Pioneer USA(a), (b)                                                                             $    3,105

Merger Value per $1,000 Limited Partner Investment(b), (c)                                      $   161.23

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the             2.93 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

        -- as of March 31, 2001(c)                                                              $    96.30

        -- as of December 31, 2000(c)                                                           $    98.36

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                               $   147.15

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                 $   156.52

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)   $      225



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2036, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                       -2-
   662

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                          Commission File No. 33-3353C


                           PARKER & PARSLEY 86-C, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                                    75-2142283
          ---------------------------------               ---------------------
           (State or other jurisdiction of                   (I.R.S. Employer
           incorporation or organization)                 Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]




   663


                           PARKER & PARSLEY 86-C, LTD.

                                TABLE OF CONTENTS




                                                                         Page
                          Part I. Financial Information
                                                                      

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000........................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000.............................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001......................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000.............................    6

           Notes to Financial Statements...............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations.......................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K............................    9

           Signatures..................................................   10



                                        2

   664



                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                           March 31,           December 31,
                                                              2001                 2000
                                                          ------------         ------------
                                                          (Unaudited)
                                                                         
                       ASSETS

Current assets:
  Cash                                                    $    157,739         $    161,347
  Accounts receivable - oil and gas sales                      293,256              296,462
                                                          ------------         ------------
          Total current assets                                 450,995              457,809
                                                          ------------         ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                      14,601,042           14,598,140
Accumulated depletion                                      (13,139,153)         (13,107,930)
                                                          ------------         ------------
          Net oil and gas properties                         1,461,889            1,490,210
                                                          ------------         ------------
                                                          $  1,912,884         $  1,948,019
                                                          ============         ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                            $     35,143         $     30,112

Partners' capital:
  Managing general partner                                      17,469               17,871
  Limited partners (19,317 interests)                        1,860,272            1,900,036
                                                          ------------         ------------
                                                             1,877,741            1,917,907
                                                          ------------         ------------
                                                          $  1,912,884         $  1,948,019
                                                          ============         ============


  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   665


                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                                 Three months ended
                                                                      March 31,
                                                          --------------------------------
                                                              2001                2000
                                                          ------------        ------------
                                                                        
Revenues:
  Oil and gas                                             $    532,204        $    417,147
  Interest                                                       3,262               2,454
                                                          ------------        ------------
                                                               535,466             419,601
                                                          ------------        ------------
Costs and expenses:
  Oil and gas production                                       217,165             216,955
  General and administrative                                    15,966              12,514
  Depletion                                                     31,223              43,157
                                                          ------------        ------------
                                                               264,354             272,626
                                                          ------------        ------------
Net income                                                $    271,112        $    146,975
                                                          ============        ============
Allocation of net income:
  Managing general partner                                $      2,711        $      1,470
                                                          ============        ============
  Limited partners                                        $    268,401        $    145,505
                                                          ============        ============
Net income per limited partnership interest               $      13.89        $       7.53
                                                          ============        ============


         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        4

   666


                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                       Managing
                                        general             Limited
                                        partner            partners              Total
                                      -----------         -----------         -----------
                                                                     
Balance at January 1, 2001            $    17,871         $ 1,900,036         $ 1,917,907

  Distributions                            (3,113)           (308,165)           (311,278)

  Net income                                2,711             268,401             271,112
                                      -----------         -----------         -----------

Balance at March 31, 2001             $    17,469         $ 1,860,272         $ 1,877,741
                                      ===========         ===========         ===========


         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        5

   667


                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                                 Three months ended
                                                                      March 31,
                                                          ---------------------------------
                                                              2001                 2000
                                                          ------------         ------------
                                                                         
Cash flows from operating activities:
  Net income                                              $    271,112         $    146,975
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                                31,223               43,157
Changes in assets and liabilities:
    Accounts receivable                                          3,206              (19,378)
    Accounts payable                                             5,031                3,790
                                                          ------------         ------------
       Net cash provided by operating activities               310,572              174,544
                                                          ------------         ------------
Cash flows used in investing activities:
   Additions to oil and gas properties                          (2,902)              (6,651)
Cash flows used in financing activities:
  Cash distributions to partners                              (311,278)            (162,999)
                                                          ------------         ------------
Net increase (decrease) in cash                                 (3,608)               4,894
Cash at beginning of period                                    161,347              142,687
                                                          ------------         ------------
Cash at end of period                                     $    157,739         $    147,581
                                                          ============         ============


         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        6


   668


              PARKER & PARSLEY 86-C, LTD.
             (A Texas Limited Partnership)

             NOTES TO FINANCIAL STATEMENTS
                 March 31, 2001
                  (Unaudited)

Note 1.   Organization and nature of operations

Parker & Parsley 86-C, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.   Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.   Management's Discussion and Analysis of Financial Condition
           and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 28% to $532,204 for the three
months ended March 31, 2001 from $417,147 for the same period in 2000. The
increase in revenues resulted from higher average prices received, offset by
declines in production. For the three months ended March 31, 2001, 9,944 barrels
of oil, 5,131 barrels of natural gas liquids ("NGLs") and 28,858 mcf of gas were
sold, or 19,885 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 11,158 barrels of oil, 5,452 barrels of NGLs and 21,750 mcf of
gas were sold, or 20,235 BOEs.

                                       7


   669



The average price received per barrel of oil increased $.40, or 1%, from $27.56
for the three months ended March 31, 2000 to $27.96 for the same period in 2001.
The average price received per barrel of NGLs increased $4.44, or 33%, from
$13.64 for the three months ended March 31, 2000 to $18.08 for the same period
in 2001. The average price received per mcf of gas increased 245% from $1.62
during the three months ended March 31, 2000 to $5.59 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses decreased to $264,354 for the three months ended March
31, 2001 as compared to $272,626 for the same period in 2000, a decrease of
$8,272, or 3%. This decrease was primarily due to a decline in depletion, offset
by increases in general and administrative expenses ("G&A") and production
costs.

Production costs were $217,165 for the three months ended March 31, 2001 and
$216,955 for the same period in 2000, an increase of $210. This increase was
primarily due to higher production taxes associated with higher oil and gas
prices, offset by lower well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 28% from $12,514 for the three months ended March 31, 2000 to $15,966
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $31,223 for the three months ended March 31, 2001 as compared to
$43,157 for the same period in 2000, a decrease of $11,934, or 28%. This
decrease was primarily due to positive revisions to proved reserves during the
three months ended March 31, 2001 as a result of higher commodity prices and a
decrease in oil production of 1,214 barrels for the three months ended March 31,
2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities:

Net cash provided by operating activities increased $136,028 for the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $115,865 in oil and gas sales receipts
and a reduction in working capital of $23,825, offset by increases in production
costs of $210 and G&A expenses of $3,452. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $115,865 to oil and gas receipts. The increase in production costs
was primarily due to increased production taxes associated with higher oil and
gas prices, offset by lower well maintenance costs. The increase in G&A was
primarily due to an increase in the accrual for tax preparation fees.


                                       8


   670



Net Cash Used in Investing Activities

The Partnership's investing activities during the three months ended March 31,
2001 and 2000 were related to upgrades of oil and gas equipment on active
properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $311,278, of which $3,113 was distributed to the managing general partner
and $308,165 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $162,999, of which $1,630 was
distributed to the managing general partner and $161,369 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1) "Item 2. Management's Discussion and Analysis of Financial Condition and
    Results of Operations" contains forward looking statements that involve
    risks and uncertainties. Accordingly, no assurances can be given that the
    actual events and results will not be materially different than the
    anticipated results described in the forward looking statements.

                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.



                                       9


   671


                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                           PARKER & PARSLEY 86-C, LTD.

                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 9, 2001                By:      /s/ Rich Dealy
                                            ---------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       10

   672
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                          COMMISSION FILE NO. 33-3353C


                           PARKER & PARSLEY 86-C, LTD.
             (Exact name of Registrant as specified in its charter)

              TEXAS                                         75-2142283
--------------------------------                     ------------------------
(State or other jurisdiction of                          (I.R.S. Employer
 incorporation or organization)                        Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS      75039
----------------------------------------------------------------   ------------
     (Address of principal executive offices)                       (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
           Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$19,257,000.

        As of March 8, 2001, the number of outstanding limited partnership
interests was 19,317.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

   673

                                     PART I

ITEM 1.       BUSINESS

Parker & Parsley 86-C, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 19,317 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 37% and 15% were attributable to sales
made to Plains Marketing, L.P. and TEPPCO Crude Oil LLC, respectively. Pioneer
USA is of the opinion that the loss of any one purchaser would not have an
adverse effect on its ability to sell its oil, natural gas liquids ("NGLs") and
gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial



                                       2
   674



liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.      PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 60
productive oil and gas wells. Four wells were sold and three wells were
abandoned due to uneconomical operations. At December 31, 2000, 53 wells were
producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.      LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.      SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                       3
   675


                                     PART II

ITEM 5.      MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
             DISTRIBUTIONS

At March 8, 2001, the Partnership had 19,317 outstanding limited partnership
interests held of record by 1,332 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $821,264 and
$236,960, respectively, were made to the limited partners.

ITEM 6.      SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:




                                     2000          1999           1998        1997          1996
                                  ----------     ---------     ---------    ---------    ---------
                                                                         
Operating results:
------------------
  Oil and gas sales               $1,865,405    $1,067,096    $  973,632   $1,484,170   $1,750,717
                                   =========     =========     =========    =========    =========

  Gain on litigation
    settlement, net               $       -     $       -     $       -    $       -    $  704,864
                                   =========     =========     =========    =========    =========

  Impairment of oil and gas
    properties                    $       -     $   26,652    $  277,277   $  895,701   $  132,778
                                   =========     =========     =========    =========    =========

  Net income (loss)               $  828,383    $  105,421    $ (423,942)  $ (577,071)  $1,142,509
                                   =========     =========     =========    =========    =========

  Allocation of net income
    (loss):
    Managing general partner      $    8,284    $    1,054    $   (4,240)  $   (5,770)  $   11,425
                                   =========     =========     =========    =========    =========

    Limited partners              $  820,099    $  104,367    $ (419,702)  $ (571,301)  $1,131,084
                                   =========     =========     =========    =========    =========

  Limited partners' net income
    (loss) per limited
    partnership interest          $    42.45    $     5.40    $   (21.73)  $   (29.58)  $    58.55
                                   =========     =========     =========    =========    =========

  Limited partners' cash
    distributions per limited
    limited partnership
    interest                      $    42.52    $    12.27    $    15.20   $    37.84   $    69.40(a)
                                   =========     =========     =========    =========    =========

At year end:
------------
  Identifiable assets             $1,948,019    $1,958,255    $2,071,111   $2,820,637   $4,193,447
                                   =========     =========     =========    =========    =========
---------------


(a) Including litigation settlement per limited partnership interest of $36.12
    in 1996.



                                       4
   676



ITEM 7.       MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 75% to $1,865,405 for 2000 as
compared to $1,067,096 in 1999. The increase in revenues resulted from higher
average prices received, offset by a slight decline in production. In 2000,
41,783 barrels of oil, 24,546 barrels of natural gas liquids ("NGLs") and 95,610
mcf of gas were sold, or 82,264 barrel of oil equivalents ("BOEs"). In 1999,
37,899 barrels of oil, 26,995 barrels of NGLs and 105,081 mcf of gas were sold,
or 82,408 BOEs. Due to the decline characteristics of the Partnership's oil and
gas properties, management expects a certain amount of decline in production in
the future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.25, or 71%, from
$17.18 in 1999 to $29.43 in 2000. The average price received per barrel of NGLs
increased $5.79, or 62%, from $9.27 in 1999 to $15.06 in 2000. The average price
received per mcf of gas increased 76% from $1.58 in 1999 to $2.78 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $1,051,119 as compared to $969,444
in 1999, an increase of $81,675, or 8%. The increase was due to increases in
production costs and general and administrative ("G&A") expenses, offset by
declines in depletion and the impairment of oil and gas properties.

Production costs were $848,089 in 2000 and $713,921 in 1999, resulting in an
increase of $134,168, or 19%. The increase was primarily due to additional well
maintenance and workover costs incurred to stimulate well production and higher
production taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
75% from $32,012 in 1999 to $55,962 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $46,688 in 2000 and $17,953 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   677



In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $26,652 related to its oil and gas properties during 1999.

Depletion was $147,068 in 2000 compared to $196,859 in 1999, representing a
decrease of $49,791, or 25%. This decrease was primarily due to a 158,291
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1999,
offset by an increase in oil production of 3,884 barrels for the period ended
December 31, 2000 compared to the same period in 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 10% to $1,067,096 from
$973,632 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 37,899 barrels of oil,
26,995 barrels of NGLs and 105,081 mcf of gas were sold, or 82,408 BOEs. In
1998, 44,016 barrels of oil, 30,658 barrels of NGLs and 129,149 mcf of gas were
sold, or 96,199 BOEs.

The average price received per barrel of oil increased $3.92, or 30%, from
$13.26 in 1998 to $17.18 in 1999. The average price received per barrel of NGL's
increased $2.81, or 43%, from $6.46 in 1998 to $9.27 in 1999. The average price
received per mcf of gas increased 6% from $1.49 in 1998 to $1.58 in 1999.

Total costs and expenses decreased in 1999 to $969,444 as compared to $1,406,971
in 1998, a decrease of $437,527, or 31%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $713,921 in 1999 and $737,587 in 1998, resulting in a
$23,666 decrease, or 3%. The decrease was due to declines in well maintenance
costs and ad valorem taxes.

During this period, G&A increased 10% from $29,209 in 1998 to $32,012 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $17,953 in
1999 and $21,776 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $26,652 and $277,277
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion was $196,859 in 1999 compared to $362,898 in 1998. This represented a
decrease of $166,039, or 46%. This decrease was primarily due to an increase in
proved reserves of 291,530 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of



                                       6
   678


1998 and a decline in oil production of 6,117 barrels for the period ended
December 31, 1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $596,449 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $804,637, offset by increases in production costs paid
of $134,168, G&A expenses paid of $23,950 and working capital of $50,070. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $753,537 to oil and gas receipts and
an increase of $51,100 resulting from the increase in oil production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices and additional well maintenance
and workover costs incurred to stimulate well production. The increase in G&A
was primarily due to higher percentage of the managing general partner's G&A
being allocated (limited to 3% of oil and gas revenues) as a result of increased
oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $847 were recognized during 1999 from
equipment credits received on active properties.




Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $829,560, of which $8,296 was
distributed to the managing general partner and $821,264 to the limited
partners. In 1999, cash distributions to the partners were $239,353, of which
$2,393 was distributed to the managing general partner and $236,960 to the
limited partners.

                                       7
   679



ITEM 8.      FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA





                                 INDEX TO FINANCIAL STATEMENTS

                                                                                         Page
                                                                                      
Financial Statements of Parker & Parsley 86-C, Ltd:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15




                                       8
   680


                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 86-C, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 86-C, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 86-C, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       9
   681



                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                    2000             1999
                                                                 -----------       ----------
              ASSETS
              ------
                                                                            
Current assets:
  Cash                                                           $   161,347      $   142,687
  Accounts receivable - oil and gas sales                            296,462          194,380
                                                                  ----------       ----------

        Total current assets                                         457,809          337,067
                                                                  ----------       ----------

Oil and gas properties - at cost, based on
  the successful efforts accounting method                        14,598,140       14,582,050
Accumulated depletion                                            (13,107,930)     (12,960,862)
                                                                  ----------       ----------

        Net oil and gas properties                                 1,490,210        1,621,188
                                                                  ----------       ----------

                                                                 $ 1,948,019      $ 1,958,255
                                                                  ==========       ==========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                   $    30,112      $    39,171

Partners' capital:
  Managing general partner                                            17,871           17,883
  Limited partners (19,317 interests)                              1,900,036        1,901,201
                                                                  ----------       ----------

                                                                   1,917,907        1,919,084
                                                                  ----------       ----------

                                                                 $ 1,948,019      $ 1,958,255
                                                                  ==========       ==========



  The accompanying notes are an integral part of these financial statements.


                                       10
   682
                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31





                                                      2000          1999         1998
                                                   ----------    ----------    ---------


                                                                     
Revenues:
  Oil and gas                                      $1,865,405    $1,067,096   $  973,632
  Interest                                             14,097         7,769        9,397
                                                    ---------     ---------    ---------

                                                    1,879,502     1,074,865      983,029
                                                    ---------     ---------    ---------

Costs and expenses:
  Oil and gas production                              848,089       713,921      737,587
  General and administrative                           55,962        32,012       29,209
  Impairment of oil and gas properties                      -        26,652      277,277
  Depletion                                           147,068       196,859      362,898
                                                    ---------     ---------    ---------

                                                    1,051,119       969,444    1,406,971
                                                    ---------     ---------    ---------

Net income (loss)                                  $  828,383    $  105,421   $ (423,942)
                                                    =========     =========    =========

Allocation of net income (loss):
  Managing general partner                         $    8,284    $    1,054   $   (4,240)
                                                    =========     =========    =========

  Limited partners                                 $  820,099    $  104,367   $ (419,702)
                                                    =========     =========    =========

Net income (loss) per limited partnership interest $    42.45    $     5.40   $   (21.73)
                                                    =========     =========    =========



  The accompanying notes are an integral part of these financial statements.



                                       11
   683
                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                   Managing
                                                    general    Limited
                                                    partner    partners     Total
                                                   --------   ---------   ---------
                                                               
Partners' capital at January 1, 1998              $  26,428  $2,747,103  $2,773,531

   Distributions                                     (2,966)   (293,607)   (296,573)

   Net loss                                          (4,240)   (419,702)   (423,942)
                                                   --------   ---------   ---------

Partners' capital at December 31, 1998               19,222   2,033,794   2,053,016

   Distributions                                     (2,393)   (236,960)   (239,353)

   Net income                                         1,054     104,367     105,421
                                                   --------   ---------   ---------

Partners' capital at December 31, 1999               17,883   1,901,201   1,919,084

   Distributions                                     (8,296)   (821,264)   (829,560)

   Net income                                         8,284     820,099     828,383
                                                   --------   ---------   ---------

Partners' capital at December 31, 2000            $  17,871  $1,900,036  $1,917,907
                                                   ========   =========   =========



  The accompanying notes are an integral part of these financial statements.



                                       12
   684
                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                      2000          1999         1998
                                                   ---------      --------      -------
                                                                   
Cash flows from operating activities:
  Net income (loss)                                $ 828,383     $ 105,421    $(423,942)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties                -         26,652      277,277
      Depletion                                      147,068       196,859      362,898
  Changes in assets and liabilities:
      Accounts receivable                           (102,082)      (82,147)      91,550
      Accounts payable                                (9,059)       21,076      (29,011)
                                                    --------      --------     --------

        Net cash provided by operating activities    864,310       267,861      278,772
                                                    --------      --------     --------

Cash flows from investing activities:
  Additions to oil and gas properties                (16,090)      (13,291)     (19,770)
  Proceeds from asset dispositions                        -            847          626
                                                    --------      --------     --------

        Net cash used in investing activities        (16,090)      (12,444)     (19,144)
                                                    --------      --------     --------

Cash flows used in financing activities:
  Cash distributions to partners                    (829,560)     (239,353)    (296,573)
                                                    --------      --------     --------

Net increase (decrease) in cash                       18,660        16,064      (36,945)
Cash at beginning of year                            142,687       126,623      163,568
                                                    --------      --------     --------

Cash at end of year                                $ 161,347     $ 142,687    $ 126,623
                                                    ========      ========     ========



  The accompanying notes are an integral part of these financial statements.



                                       13
   685



                           PARKER & PARSLEY 86-C, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 86-C, Ltd. (the "Partnership") is a limited partnership
organized in 1986 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.



                                       14
   686



        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.      IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions $26,652 and $277,277
related to its proved oil and gas properties during 1999 and 1998, respectively.

NOTE 4.      INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $533,255 less than the tax basis at December 31, 2000.



                                       15
   687
      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                         2000          1999          1998
                                                       --------      --------       --------

                                                                          
  Net income (loss) per statements of operations      $ 828,383     $ 105,421      $(423,942)
  Depletion and depreciation provisions for tax
    reporting purposes less than amounts for
    financial reporting purposes                        132,379       182,068        348,153
  Impairment of oil and gas properties for financial
    reporting purposes                                       -         26,652        277,277
  Salvage income                                             -             -             431
  Other, net                                             (2,097)       (2,839)         4,014
                                                       --------      --------       --------

       Net income per Federal income tax
         returns                                      $ 958,665     $ 311,302      $ 205,933
                                                       ========      ========       ========



NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:




                                                      2000          1999           1998
                                                    --------      --------       --------
                                                                       
    Development costs                              $  16,090     $  13,291      $  19,770
                                                    ========      ========       ========


    Capitalized oil and gas properties consist of the following:




                                                                  2000             1999
                                                               ----------       ----------

                                                                        
      Proved properties:
        Property acquisition costs                           $    645,990     $    645,990
        Completed wells and equipment                          13,952,150       13,936,060
                                                               ----------       ----------

                                                               14,598,140       14,582,050
      Accumulated depletion                                    (13,107,930)    (12,960,862)
                                                               -----------     -----------

              Net oil and gas properties                     $  1,490,210     $  1,621,188
                                                              ===========      ===========


                                       16
   688
NOTE 6.      RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                      2000          1999          1998
                                                    --------     ---------       --------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 373,973     $ 354,129      $ 348,965

    Reimbursement of general and administrative
      expenses                                     $  46,688     $  17,953      $  21,776


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA and the Partnership are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:




                                                               Pioneer USA (1)    Partnership
                                                              ---------------   ---------------

                                                                         
   Revenues:
     Proceeds from disposition of depreciable properties         9.09091%        90.90909%
     All other revenues                                         24.242425%       75.757575%

   Costs and expenses:
     Lease acquisition costs, drilling and completion costs
       and all other costs                                       9.09091%        90.90909%
     Operating costs, direct costs and general and
       administrative expenses                                  24.242425%       75.757575%




(1)     Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level and 60 limited partner interests owned by
        Pioneer USA.

NOTE 7.       OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       17
   689





                                                              Oil and NGLs         Gas
                                                                 (bbls)           (mcf)
                                                              ------------      ----------

                                                                        
  Net proved reserves at January 1, 1998                          831,525        1,374,642
  Revisions                                                      (383,916)        (502,202)
  Production                                                      (74,674)        (129,149)
                                                              -----------       ----------

  Net proved reserves at December 31, 1998                        372,935          743,291
  Revisions                                                       507,962          924,982
  Production                                                      (64,894)        (105,081)
                                                              -----------       ----------

  Net proved reserves at December 31, 1999                        816,003        1,563,192
  Revisions                                                       148,591         (208,305)
  Production                                                      (66,329)         (95,610)
                                                              -----------       ----------

  Net proved reserves at December 31, 2000                        898,265        1,259,277
                                                              ===========       ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.39 per barrel of NGLs and $7.64 per mcf of gas,
discounted at 10% was approximately $6,568,000 and undiscounted was $12,019,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                       18
   690





                                                                   For the years ended December 31,
                                                                 -----------------------------------
                                                                    2000         1999         1998
                                                                 ----------    ---------    --------
                                                                            (in thousands)
                                                                                 
Oil and gas producing activities:
  Future cash inflows                                           $   29,187    $   20,004   $   4,058
  Future production costs                                          (17,168)      (12,833)     (3,287)
                                                                 ---------     ---------    --------

                                                                    12,019         7,171         771
  10% annual discount factor                                        (5,451)       (3,031)       (217)
                                                                 ---------     ---------    --------

  Standardized measure of discounted future net cash flows      $    6,568    $    4,140    $    554
                                                                 =========     =========     =======





                                                                     For the years ended December 31,
                                                                 -------------------------------------
                                                                    2000          1999         1998
                                                                 ----------     ---------    --------
                                                                             (in thousands)
                                                                                   
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs                   $   (1,017)   $      (353) $     (236)
    Net changes in prices and production costs                        2,672          1,767      (2,176)
    Revisions of previous quantity estimates                            714          3,173        (425)
    Accretion of discount                                               414             55         323
    Changes in production rates, timing and other                      (355)        (1,056)       (163)
                                                                   --------      ---------    --------

    Change in present value of future net revenues                    2,428          3,586      (2,677)
                                                                   --------      ---------    --------

    Balance, beginning of year                                        4,140            554       3,231
                                                                   --------      ---------    --------

    Balance, end of year                                         $    6,568    $     4,140  $      554
                                                                  =========     ==========   =========



NOTE 8.      MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:




                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                      
           Plains Marketing, L.P.                     37%           36%             -
           TEPPCO Crude Oil LLC                       15%           14%             -
           Genesis Crude Oil, L.P.                     -             -             50%
           Western Gas Resources Inc.                  5%            7%            31%



        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and TEPPCO Crude Oil LLP were $72,179 and $15,378, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:


        Managing general partner - The general partner of the Partnership is
        Pioneer USA. Pioneer USA, the managing general partner, has the power
        and authority to manage, control and administer all Partnership affairs.
        As managing general partner and operator of the Partnership's
        properties, all production expenses are incurred by Pioneer USA and
        billed to the Partnership. The majority of the Partnership's oil and gas
        revenues are received directly by the Partnership, however, a portion of
        the oil and gas revenue is initially received by Pioneer USA prior to
        being paid to the Partnership. Under the limited partnership agreement,
        the managing general partner pays 1% of the Partnership's acquisition,
        drilling and completion costs and 1% of its operating and general and
        administrative expenses. In return, it is allocated 1% of the
        Partnership's revenues.

                                       19
   691
        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $19,317,000. Pioneer USA is required to contribute amounts equal to 1%
        of initial Partnership capital less commission and offering expenses
        allocated to the limited partners and to contribute amounts necessary to
        pay costs and expenses allocated to it under the Partnership agreement
        to the extent its share of revenues does not cover such costs.

ITEM 9.        CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                 AND FINANCIAL DISCLOSURE

None.



                                       20
   692



                                    PART III

ITEM 10.      DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.




                                      Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------
                                                 
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer



        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   693



        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   694



ITEM 11.        EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.        SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 60 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                       23
   695




                                                       2000          1999           1998
                                                   ------------- -------------  -------------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $373,973      $ 354,129      $348,965

    Reimbursement of general and administrative
      expenses                                     $ 46,688      $  17,953      $ 21,776



Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.




                                       24
   696


                                     PART IV

ITEM 14.      EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)  1.   Financial statements

          The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                  1999 and 1998

                Statements of partners' capital for the years ended December 31,
                 2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                  1999 and 1998

                Notes to financial statements

     2.   Financial statement schedules

          All financial statement schedules have been omitted since the
          required information is in the financial statements or notes thereto,
          or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   697


                                   SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 86-C, LTD.

Dated: March 27, 2001               By:   Pioneer Natural Resources USA, Inc.
                                          Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                -------------------------------
                                                Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.






                                                                       
/s/ Scott D. Sheffield              President of Pioneer USA                  March 27, 2001
------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 27, 2001
------------------------------      Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 27, 2001
------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 27, 2001
------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 27, 2001
------------------------------      Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 27, 2001
------------------------------      Officer of Pioneer USA
Rich Dealy




                                       26
   698


                           PARKER & PARSLEY 86-C, LTD.

                                INDEX TO EXHIBITS

        The following documents are incorporated by reference in response to
Item 14(c):


Exhibit No.                   Description                              Page
-----------                   -----------                              ----

    3(a)        Amended and Restated Certificate of                     -
                Limited Partnership of Parker & Parsley
                86-C, Ltd. incorporated by reference to
                Exhibit 3a of the Partnership's Registration
                Statement on Form S-1 (Registration No.
                33-3353) (hereinafter called the Partnership's
                Registration Statement)

    4(a)        Form of Agreement of Limited Partnership of             -
                Parker & Parsley 86-C, Ltd. incorporated by
                reference to Exhibit A of Amendment No. 1 of
                the Partnership's Registration Statement

    4(b)        Form of Subscription Agreement incorporated by
                reference to Exhibit C of Amendment No. 1 of
                the Partnership's Registration Statement                -

    4(b)        Power of Attorney incorporated by reference to an       -
                Exhibit of the Partnership's Registration
                Statement

    4(c)        Specimen Certificate of Limited Partnership             -
                Interest incorporated by reference to Exhibit
                4c of the Partnership's Registration Statement

   10(b)        Development Program Agreement incorporated              -
                by reference to Exhibit B of Amendment No. 1
                of the Partnership's Registration Statement





                                       27


   699




                           PARKER & PARSLEY 86-C, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  417,147   $1,865,405   $1,067,096   $  973,632   $1,484,170   $1,750,717
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $     --   $       --   $       --   $       --   $       --   $       --   $  704,864
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
      properties                   $          $       --   $       --   $   26,652   $  277,277   $  895,701   $  132,778
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  146,975   $  828,383   $  105,421   $ (423,942)  $ (577,071)  $1,142,509
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
         partner                   $          $    1,470   $    8,284   $    1,054   $   (4,240)  $   (5,770)  $   11,425
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  145,505   $  820,099   $  104,367   $ (419,702)  $ (571,301)  $1,131,084
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
      (loss) per limited
      partnership interest         $          $     7.53   $    42.45   $     5.40   $   (21.73)  $   (29.58)  $    58.55
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
      distributions per limited
      limited partnership
      interest                     $          $     8.35   $    42.52   $    12.27   $    15.20   $    37.84   $    69.40(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,946,021   $1,948,019   $1,958,255   $2,071,111   $2,820,637   $4,193,447
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $36.12
     in 1996.



   700
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

    PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Private Investment 86, Ltd. and supplements the proxy statement/prospectus dated
     , 2001, of Pioneer Natural Resources Company and Pioneer Natural Resources
USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Private Investment 86, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                       -1-
   701

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                             
Aggregate Initial Investment by the Limited Partners(a)                                         $   4,920

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                     $   8,041

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding
Pioneer USA(a), (b)                                                                             $   1,251

Merger Value per $1,000 Limited Partner Investment(b), (c)                                      $  254.33

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the            3.55 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

        -- as of March 31, 2001(c)                                                              $  176.82

        -- as of December 31, 2000(c)                                                           $  183.56

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                               $  239.86

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                 $  246.79

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)   $     225



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2036, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                       -2-
   702

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   703

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS




                                                  March 31,      December 31,
                                                     2001            2000
                                                 ------------    ------------
                                                 (Unaudited)
                                                           
                 ASSETS

Current assets:
  Cash                                           $     54,067    $     57,176
  Accounts receivable - oil and gas sales              78,557          90,053
                                                 ------------    ------------
        Total current assets                          132,624         147,229
                                                 ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              4,032,771       4,032,771
Accumulated depletion                              (3,274,258)     (3,261,600)
                                                 ------------    ------------
        Net oil and gas properties                    758,513         771,171
                                                 ------------    ------------
                                                 $    891,137    $    918,400
                                                 ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $     11,426    $      5,165

Partners' capital:
  Managing general partner                              9,765          10,101
  Limited partners (123 interests)                    869,946         903,134
                                                 ------------    ------------
                                                      879,711         913,235
                                                 ------------    ------------
                                                 $    891,137    $    918,400
                                                 ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   704

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  159,338   $  139,554
  Interest                                         1,103          954
                                              ----------   ----------
                                                 160,441      140,508
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                          65,449       72,738
  General and administrative                       3,187        2,791
  Depletion                                       12,658       14,788
                                              ----------   ----------
                                                  81,294       90,317
                                              ----------   ----------
Net income                                    $   79,147   $   50,191
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $      791   $      502
                                              ==========   ==========
  Limited partners                            $   78,356   $   49,689
                                              ==========   ==========
Net income per limited partnership interest   $   637.04   $   403.98
                                              ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   705

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                              Managing
                               general      Limited
                               partner      partners        Total
                             ----------    ----------    ----------
                                                
Balance at January 1, 2001   $   10,101    $  903,134    $  913,235

    Distributions                (1,127)     (111,544)     (112,671)

    Net income                      791        78,356        79,147
                             ----------    ----------    ----------

Balance at March 31, 2001    $    9,765    $  869,946    $  879,711
                             ==========    ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   706

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                        Three months ended
                                                             March 31,
                                                     ------------------------
                                                        2001          2000
                                                     ----------    ----------
                                                             
Cash flows from operating activities:
  Net income                                         $   79,147    $   50,191
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         12,658        14,788
  Changes in assets and liabilities:
       Accounts receivable                               11,496        (9,575)
       Accounts payable                                   6,261         1,148
                                                     ----------    ----------
         Net cash provided by operating activities      109,562        56,552
                                                     ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                        --        (8,932)

Cash flows used in financing activities:
  Cash distributions to partners                       (112,671)      (69,912)
                                                     ----------    ----------
Net decrease in cash                                     (3,109)      (22,292)
Cash at beginning of period                              57,176        72,318
                                                     ----------    ----------
Cash at end of period                                $   54,067    $   50,026
                                                     ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   707

                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.  Organization and nature of operations

Parker & Parsley Private  Investment 86, Ltd. (the  "Partnership")  is a limited
partnership organized in 1986 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 14% to $159,338 for the three
months ended March 31, 2001 as compared to $139,554 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 3,129
barrels of oil, 1,034 barrels of natural gas liquids ("NGLs") and 8,951 mcf of
gas were sold, or 5,655 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 3,720 barrels of oil, 1,704 barrels of NGLs and 7,936 mcf
of gas were sold, or 6,747 BOEs.



                                        6
   708

The average price received per barrel of oil increased $1.00, or 4%, from $27.55
for the three months ended March 31, 2000 to $28.55 for the same period in 2001.
The average price received per barrel of NGLs increased $4.99, or 37%, from
$13.33 for the three months ended March 31, 2000 to $18.32 for the same period
in 2001. The average price received per mcf of gas increased 215% from $1.81
during the three months ended March 31, 2000 to $5.70 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses decreased to $81,294 for the three months ended March
31, 2001 as compared to $90,317 for the same period in 2000, a decrease of
$9,023, or 10%. This decrease was due to declines in production costs and
depletion, offset by an increase in general and administrative expenses ("G&A").

Production costs were $65,449 for the three months ended March 31, 2001 and
$72,738 for the same period in 2000 resulting in a $7,289 decrease, or 10%. The
decrease was primarily due to a decrease in well maintenance costs, offset by
higher production taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 14% from $2,791 for the three months ended March 31, 2000 to $3,187
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $12,658 for the three months ended March 31, 2001 compared to
$14,788 for the same period in 2000, a decrease of $2,130, or 14%. This decrease
was primarily due to a decline in oil production of 591 barrels for the period
ended March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $53,010 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to increases in oil and gas sales receipts of $19,933 and
reductions in working capital of $26,184 and production costs of $7,289, offset
by an increase G&A expenses of $396. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $43,293 to oil and gas receipts, offset by $23,360 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
decrease in production costs was primarily due to a decrease in well maintenance



                                        7
   709

costs, offset by higher production taxes associated with higher oil and gas
prices. The increase in G&A was primarily due to an increase in the accrual for
tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $112,671, of which $1,127 was distributed to the managing general partner
and $111,544 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $69,912, of which $699 was distributed
to the managing general partner and $69,213 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.


----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   710
                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   711


                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Private Investment 86, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley Private Investment 86,
Ltd. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Private
Investment 86, Ltd. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.



                                              Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   712


                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                                                   2000                1999
                                                                                             ----------------    ----------------
                     ASSETS
                     ------

                                                                                                           
Current assets:
  Cash                                                                                       $        57,176     $        72,318
  Accounts receivable - oil and gas sales                                                             90,053              49,878
                                                                                               -------------       -------------

           Total current assets                                                                      147,229             122,196
                                                                                               -------------       -------------

Oil and gas properties - at cost, based on
  the successful efforts accounting method                                                         4,032,771           4,022,126
Accumulated depletion                                                                             (3,261,600)         (3,212,495)
                                                                                               -------------       -------------

           Net oil and gas properties                                                                771,171             809,631
                                                                                               -------------       -------------

                                                                                             $       918,400     $       931,827
                                                                                              ==============      ==============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                                               $         5,165     $        10,250

Partners' capital:
  Managing general partner                                                                            10,101              10,184
  Limited partners (123 interests)                                                                   903,134             911,393
                                                                                               -------------       -------------

                                                                                                     913,235             921,577
                                                                                               -------------       -------------

                                                                                             $       918,400     $       931,827
                                                                                              ==============      ==============
















   The accompanying notes are an integral part of these financial statements.



                                       3
   713


                 PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                        (A Texas Limited Partnership)

                           STATEMENTS OF OPERATIONS
                       For the years ended December 31






                                                       2000        1999          1998
                                                     ---------   ---------     ---------
                                                                      
Revenues:
  Oil and gas                                        $ 611,774   $ 354,462    $  301,556
  Interest                                               4,927       2,697         3,224
                                                     ---------   ---------    ----------

                                                       616,701     357,159       304,780
                                                     ---------   ---------    ----------

Costs and expenses:
  Oil and gas production                               287,563     236,129       213,042
  General and administrative                            12,235       7,089         6,031
  Impairment of oil and gas properties                      --          --        98,274
  Depletion                                             49,103      65,740       151,842
                                                     ---------   ---------    ----------

                                                       348,901     308,958       469,189
                                                     ---------   ---------    ----------

Net income (loss)                                    $ 267,800   $  48,201    $ (164,409)
                                                     =========   =========    ==========

Allocation of net income (loss):
  Managing general partner                           $   2,678   $     482    $   (1,644)
                                                     =========   =========    ==========

  Limited partners                                   $ 265,122   $  47,719    $ (162,765)
                                                     =========   =========    ==========

Net income (loss) per limited partnership interest   $2,155.46   $  387.96    $(1,323.29)
                                                     =========   =========    ==========




   The accompanying notes are an integral part of these financial statements.



                                       4
   714


                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                                            Managing
                                                                            general             Limited
                                                                            partner             partners               Total
                                                                        -------------        --------------       ---------------


                                                                                                         
Partners' capital at January 1, 1998                                    $      13,138        $    1,203,846       $   1,216,984

   Distributions                                                               (1,107)             (109,619)           (110,726)

   Net loss                                                                    (1,644)             (162,765)           (164,409)
                                                                          -----------          ------------         -----------

Partners' capital at December 31, 1998                                         10,387               931,462             941,849

   Distributions                                                                 (685)              (67,788)            (68,473)

   Net income                                                                     482                47,719              48,201
                                                                          -----------          ------------         -----------

Partners' capital at December 31, 1999                                         10,184               911,393             921,577

   Distributions                                                               (2,761)             (273,381)           (276,142)

   Net income                                                                   2,678               265,122             267,800
                                                                          -----------          ------------         -----------

Partners' capital at December 31, 2000                                  $      10,101        $      903,134       $     913,235
                                                                         ============         =============        ============










   The accompanying notes are an integral part of these financial statements.



                                       5
   715


                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                                             2000                 1999                1998
                                                                        --------------       --------------      --------------
                                                                                                        
Cash flows from operating activities:
    Net income (loss)                                                   $     267,800        $      48,201       $     (164,409)
    Adjustments to reconcile net income (loss) to
       net cash provided by operating activities:
          Impairment of oil and gas properties                                    -                    -                 98,274
          Depletion                                                            49,103               65,740              151,842
    Changes in assets and liabilities:
          Accounts receivable                                                 (40,175)             (18,067)              21,645
          Accounts payable                                                     (5,085)               5,541               (8,987)
                                                                           ----------          -----------         ------------

              Net cash provided by operating activities                       271,643              101,415               98,365
                                                                          -----------          -----------         ------------

Cash flows from investing activities:
    Additions to oil and gas properties                                       (10,643)              (7,363)              (9,842)
    Proceeds from asset dispositions                                              -                    701                  -
                                                                          -----------          -----------         ------------

              Net cash used in investing activities                           (10,643)              (6,662)              (9,842)
                                                                          -----------          -----------         ------------

Cash flows used in financing activities:
    Cash distributions to partners                                           (276,142)             (68,473)            (110,726)
                                                                          -----------          -----------         ------------

Net increase (decrease) in cash                                               (15,142)              26,280              (22,203)
Cash at beginning of year                                                      72,318               46,038               68,241
                                                                          -----------          -----------         ------------

Cash at end of year                                                     $      57,176        $      72,318       $       46,038
                                                                         ============         ============        =============

















   The accompanying notes are an integral part of these financial statements.



                                       6
   716


                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley Private Investment 86, Ltd. (the "Partnership") is a
limited partnership organized in 1986 under the laws of the State of Texas. The
Partnership's managing general partner is Pioneer Natural Resources USA, Inc.
("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   717

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS


        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $98,274 related to its
proved oil and gas properties during 1998.



                                       8
   718

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $209,861 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------

                                                                                                         
      Net income (loss) per statements of operations                     $     267,800       $      48,201        $    (164,409)
      Depletion and depreciation provisions for tax reporting
        less than amounts for financial reporting purposes                      43,051              60,686              147,947
      Impairment of oil and gas properties for financial
        reporting purposes                                                         -                   -                 98,274
      Other, net                                                                  (688)                (98)                 931
                                                                           -----------        ------------          -----------

              Net income per Federal income tax returns                  $     310,163       $     108,789        $      82,743
                                                                          ============        ============         ============


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------

                                                                                                         
      Development costs                                                  $      10,643       $       7,363        $       9,842
                                                                          ============        ============         ============


        Capitalized oil and gas properties consist of the following:


                                                                                                   2000                 1999
                                                                                             ----------------     ----------------

                                                                                                            
      Proved properties:
        Property acquisition costs                                                           $      176,667       $      176,667
        Completed wells and equipment                                                             3,856,104            3,845,459
                                                                                               ------------         ------------

                                                                                                  4,032,771            4,022,126
      Accumulated depletion                                                                      (3,261,600)          (3,212,495)
                                                                                               ------------         ------------

        Net oil and gas properties                                                           $      771,171       $      809,631
                                                                                              =============        =============


NOTE 6. RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------
                                                                                                         
     Payment of lease operating and supervision
        charges in accordance with standard industry
        operating agreements                                            $     113,494        $     109,568        $     108,785

     Reimbursement of general and administrative expenses               $      10,107        $       3,583        $       4,004




                                       9
   719

        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and the Partnership are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:


                                                                                        Pioneer USA (1)             Partnership
                                                                                        ---------------           ---------------
                                                                                                         
        Revenues:
           Proceeds from disposition of depreciable
              properties                                                                     9.09091%               90.90909%
           All other revenues                                                               24.242425%              75.757575%
        Costs and expenses:
           Lease acquisition costs, drilling and completion
              costs and all other costs                                                      9.09091%               90.90909%
           Operating costs, direct costs and general and
              administrative expenses                                                       24.242425%              75.757575%


        (1)     Excludes Pioneer USA's 1% general partner ownership which is
                allocated at the Partnership level.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                                                             Oil and NGLs                 Gas
                                                                                (bbls)                    (mcf)
                                                                         --------------------      -------------------

                                                                                             
     Net proved reserves at January 1, 1998                                      268,312                   360,572
     Revisions                                                                   (79,340)                  (72,226)
     Production                                                                  (22,245)                  (33,219)
                                                                           -------------              ------------

     Net proved reserves at December 31, 1998                                    166,727                   255,127
     Revisions                                                                   157,207                   248,047
     Production                                                                  (20,843)                  (30,923)
                                                                           -------------              ------------

     Net proved reserves at December 31, 1999                                    303,091                   472,251
     Revisions                                                                    35,219                    57,281
     Production                                                                  (20,938)                  (33,570)
                                                                           -------------              ------------

     Net proved reserves at December 31, 2000                                    317,372                   495,962
                                                                           =============              ============




        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.44 per barrel of NGLs and $7.89 per mcf of gas,
discounted at 10% was approximately $2,493,000 and undiscounted $4,970,000.



                                       10
   720

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                                  For the years ended December 31,
                                                                        -------------------------------------------------------
                                                                              2000                1999               1998
                                                                        ----------------    ----------------   ----------------
                                                                                                  (in thousands)
                                                                                                      
Oil and gas producing activities:
   Future cash inflows                                                  $        10,955     $        7,464     $         1,802
   Future production costs                                                       (5,985)            (4,360)             (1,436)
                                                                          -------------       ------------       -------------

                                                                                  4,970              3,104                 366
   10% annual discount factor                                                    (2,477)            (1,468)               (105)
                                                                          -------------       ------------       -------------

   Standardized measure of discounted future net cash flows             $         2,493     $        1,636     $           261
                                                                         ==============      =============      ==============












                                       11
   721




                                                                              For the years ended December 31,
                                                                    -------------------------------------------------------
                                                                          2000                1999               1998
                                                                    ----------------    ----------------   ----------------
                                                                                              (in thousands)
                                                                                                  
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs                    $          (324)    $         (118)    $          (89)
      Net changes in prices and production costs                                864                922               (654)
      Revisions of previous quantity estimates                                  293              1,155                (93)
      Accretion of discount                                                     164                 26                102
      Changes in production rates, timing and other                            (140)              (610)               (25)
                                                                      -------------       ------------       ------------

      Change in present value of future net revenues                            857              1,375               (759)
                                                                      -------------       ------------       ------------

      Balance, beginning of year                                              1,636                261              1,020
                                                                      -------------       ------------       ------------

      Balance, end of year                                          $         2,493     $        1,636     $          261
                                                                     ==============      =============      =============


NOTE 8.  MAJOR CUSTOMERS

   The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:


                                                                                 2000              1999                1998
                                                                               --------          --------            --------
                                                                                                            
                   Plains Marketing, L.P.                                         45%               45%                   -
                   Mobil Oil Corporation                                          19%               18%                  18%
                   Genesis Crude Oil, L.P.                                         -                 -                   46%
                   Western Gas Resources, Inc.                                     3%                5%                  21%


        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and Mobil Oil Corporation were $23,848 and $10,948, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

         The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Partnership affairs. As managing
        general partner and operator of the Partnership's properties, all
        production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $4,920,000. Pioneer USA is required to contribute amounts equal to 1% of
        initial Partnership capital less commission and organization and
        offering costs



                                       12
   722

        allocated to the limited partners and to contribute amounts necessary to
        pay costs and expenses allocated to it under the Partnership agreement
        to the extent its share of revenues does not cover such costs.



                                       13




   723
                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 73% to $611,774 for 2000 as
compared to $354,462 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 13,860 barrels
of oil, 7,078 barrels of natural gas liquids ("NGLs") and 33,570 mcf of gas were
sold, or 26,533 barrel of oil equivalents ("BOEs"). In 1999, 13,331 barrels of
oil, 7,512 barrels of NGLs and 30,923 mcf of gas were sold, or 25,997 BOEs. Due
to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.11, or 70%, from
$17.34 in 1999 to $29.45 in 2000. The average price received per barrel of NGLs
increased $5.74, or 62%, from $9.27 in 1999 to $15.01 in 2000. The average price
received per mcf of gas increased 68% from $1.73 in 1999 to $2.90 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $348,901 as compared to $308,958
in 1999, an increase of $39,943, or 13%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $287,563 in 2000 and $236,129 in 1999, resulting in a
$51,434 increase, or 22%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
73% from $7,089 in 1999 to $12,235 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 2% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $10,107 in 2000 and $3,583 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $49,103 in 2000 as compared to $65,740 in 1999, representing a
decrease of $16,637, or 25%. This decrease was primarily due to a 34,384 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 18% to $354,462 from
$301,556 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 13,331 barrels of oil,
7,512 barrels of NGLs and 30,923 mcf of gas were sold, or 25,997 BOEs. In 1998,
14,914 barrels of oil, 7,331 barrels of NGLs and 33,219 mcf of gas were sold, or
27,782 BOEs.




   724

The average price received per barrel of oil increased $4.00, or 30%, from
$13.34 in 1998 to $17.34 in 1999. The average price received per barrel of NGLs
increased $2.58, or 39%, from $6.69 in 1998 to $9.27 in 1999. The average price
received per mcf of gas increased 7% from $1.61 in 1998 to $1.73 in 1999.

Total costs and expenses decreased in 1999 to $308,958 as compared to $469,189
in 1998, a decrease of $160,231, or 34%. The decrease was primarily due to
declines in the impairment of oil and gas properties and depletion, offset by
increases in production costs and G&A.

Production costs were $236,129 in 1999 and $213,042 in 1998, resulting in a
$23,087 increase, or 11%. The increase was due to increased workover costs and
well maintenance costs incurred to stimulate well production, offset by a
decrease in ad valorem taxes.

During this period, G&A increased 18% from $6,031 in 1998 to $7,089 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 2% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $3,583 in
1999 and $4,004 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $98,274 related to its oil and gas properties during 1998.

Depletion was $65,740 in 1999 compared to $151,842 in 1998, representing a
decrease of $86,102, or 57%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 97,690 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 1,583
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum Industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $170,228 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $259,542, offset by increases in production costs paid
of $51,434, G&A expenses paid of $5,146 and working capital of $32,734. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $242,798 to oil and gas receipts and
an increase of $16,744 resulting from the increase in production during 2000.
The increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 2%
of oil and gas revenues) as a result of increased oil and gas revenues.




   725

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on various oil and gas properties.

Proceeds from asset dispositions in 1999 of $701 were from equipment credits
received on two wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $276,142, of which $2,761 was
distributed to the managing general partner and $273,381 to the limited
partners. In 1999, cash distributions to the partners were $68,473, of which
$685 was distributed to the managing general partner and $67,788 to the limited
partners.






   726




                  PARKER & PARSLEY PRIVATE INVESTMENT 86, LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  139,554   $  611,774   $  354,462   $  301,556   $  443,324   $  531,378
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   98,274   $   87,003   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $          $       --   $       --   $       --   $       --   $       --   $  181,309
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   50,191   $  267,800   $   48,201   $ (164,409)  $   (1,482)  $  394,220
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      502   $    2,678   $      482   $   (1,644)  $      (15)  $    3,942
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   49,689   $  265,122   $   47,719   $ (162,765)  $   (1,467)  $  390,278
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   403.98   $ 2,155.46   $   387.96   $(1,323.29)  $   (11.93)  $ 3,172.99
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   562.71   $ 2,222.61   $   551.12   $   891.21   $ 1,688.39   $ 3,519.32(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  913,254   $  918,400   $  931,827   $  946,558   $1,230,680   $1,439,437
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of
     $1,474.06 in 1996.



   727
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

         PARKER & PARSLEY 87-A CONV., LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED          , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS          , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
87-A Conv., Ltd. and supplements the proxy statement/prospectus dated        ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 87-A Conv., Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                       -1-
   728
                        PARKER & PARSLEY 87-A CONV., LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                             
Aggregate Initial Investment by the Limited Partners(a)                                         $   3,856

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                     $   5,136

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding
Pioneer USA(a), (b)                                                                             $     731

Merger Value per $1,000 Limited Partner Investment(b), (c)                                      $  191.35

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the            3.23 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

        -- as of March 31, 2001(c)                                                              $  110.28

        -- as of December 31, 2000(c)                                                           $  113.34

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                               $  177.22

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                 $  185.78

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)   $     177



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                       -2-
   729

                        PARKER & PARSLEY 87-A CONV., LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   730



                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS





                                                   March 31,     December 31,
                                                     2001            2000
                                                 ------------    ------------
                                                 (Unaudited)
                                                           
                 ASSETS

Current assets:
  Cash                                           $     39,395    $     42,044
  Accounts receivable - oil and gas sales              61,076          58,386
                                                 ------------    ------------
        Total current assets                          100,471         100,430
                                                 ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              2,703,134       2,703,338
Accumulated depletion                              (2,367,060)     (2,357,166)
                                                 ------------    ------------
        Net oil and gas properties                    336,074         346,172
                                                 ------------    ------------
                                                 $    436,545    $    446,602
                                                 ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $      7,009    $      5,133

Partners' capital:
  Managing general partner                              4,297           4,417
  Limited partners (3,856 interests)                  425,239         437,052
                                                 ------------    ------------
                                                      429,536         441,469
                                                 ------------    ------------
                                                 $    436,545    $    446,602
                                                 ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   731

                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  103,709   $   86,783
  Interest                                           729          693
  Gain on disposition of assets                      321          784
                                              ----------   ----------
                                                 104,759       88,260
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                          38,017       35,526
  General and administrative                       3,111        2,603
  Depletion                                        9,894        6,938
                                              ----------   ----------
                                                  51,022       45,067
                                              ----------   ----------
Net income                                    $   53,737   $   43,193
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $      537   $      432
                                              ==========   ==========
  Limited partners                            $   53,200   $   42,761
                                              ==========   ==========
Net income per limited partnership interest   $    13.80   $    11.09
                                              ==========   ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                       3
   732

                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                              Managing
                               general      Limited
                               partner      partners        Total
                             ----------    ----------    ----------
                                                
Balance at January 1, 2001   $    4,417    $  437,052    $  441,469

    Distributions                  (657)      (65,013)      (65,670)

    Net income                      537        53,200        53,737
                             ----------    ----------    ----------

Balance at March 31, 2001    $    4,297    $  425,239    $  429,536
                             ==========    ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   733

                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                        Three months ended
                                                             March 31,
                                                     ------------------------
                                                        2001          2000
                                                     ----------    ----------
                                                             
Cash flows from operating activities:
  Net income                                         $   53,737    $   43,193
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                          9,894         6,938
       Gain on disposition of assets                       (321)         (784)
  Changes in assets and liabilities:
       Accounts receivable                               (2,690)       (4,510)
       Accounts payable                                   1,876         1,450
                                                     ----------    ----------
         Net cash provided by operating activities       62,496        46,287
                                                     ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                      (112)         (612)
  Proceeds from asset dispositions                          637         1,016
                                                     ----------    ----------
         Net cash provided by investing activities          525           404
                                                     ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                        (65,670)      (45,111)
                                                     ----------    ----------
Net increase (decrease) in cash                          (2,649)        1,580
Cash at beginning of period                              42,044        53,265
                                                     ----------    ----------
Cash at end of period                                $   39,395    $   54,845
                                                     ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   734

                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.  Organization and nature of operations

Parker & Parsley 87-A Conv., Ltd. (the "Partnership") was organized in 1987 as a
general  partnership under the laws of the State of Texas and was converted to a
Texas limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 20% to $103,709 for the three
months ended March 31, 2001 as compared to $86,783 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 1,910
barrels of oil, 1,022 barrels of natural gas liquids ("NGLs") and 5,718 mcf of
gas were sold, or 3,885 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 2,186 barrels of oil, 1,182 barrels of NGLs and 5,425 mcf
of gas were sold, or 4,272 BOEs.



                                        6
   735

The average price received per barrel of oil increased $.66, or 2%, from $27.18
for the three months ended March 31, 2000 to $27.84 for the same period in 2001.
The average price received per barrel of NGLs increased $3.50, or 23%, from
$15.12 for the three months ended March 31, 2000 to $18.62 for the same period
in 2001. The average price received per mcf of gas increased 215% from $1.75
during the three months ended March 31, 2000 to $5.51 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gains on disposition of assets of $321 and $784 were due to equipment credits
received on one well during the three months ended March 31, 2001 and 2000,
respectively.

Costs and Expenses:

Total costs and expenses increased to $51,002 for the three months ended March
31, 2001 as compared to $45,067 for the same period in 2000, an increase of
$5,935, or 13%. This increase was due to increases in depletion, production
costs and general and administrative expenses ("G&A").

Production costs were $38,017 for the three months ended March 31, 2001 and
$35,526 for the same period in 2000 resulting in a $2,491 increase, or 7%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices and additional well maintenance costs incurred to stimulate well
production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 20% from $2,603 for the three months ended March 31, 2000 to $3,111
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $9,894 for the three months ended March 31, 2001 compared to
$6,938 for the same period in 2000, an increase of $2,956, or 43%. This increase
was primarily due to a downward revision to one well's proved reserves, offset
by a decline in oil production of 276 barrels during the three months ended
March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $16,209 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was primarily attributable to an increase of $16,962 in oil and gas
sales receipts and a reduction in working capital of $2,246, offset by increases
in production costs of $2,491 and G&A expenses of $508. The increase in oil and
gas receipts resulted from the increase in commodity prices during 2001 which
contributed an additional $26,008 to oil and gas receipts, offset by $9,046



                                        7
   736

resulting from the decline in production during 2001 as compared to the same
period in 2000. The increase in production costs was primarily due to increased
production taxes associated with higher oil and gas prices and well maintenance
costs incurred to stimulate well production. The increase in G&A was primarily
due to an increase in the accrual for tax preparation fees.

Net Cash Provided by Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's principle
investing activities included expenditures related to equipment upgrades on
active oil and gas properties.

Proceeds from asset dispositions of $637 and $1,016 received during the three
months ended March 31, 2001 and 2000, respectively, were comprised of $321 and
$784, respectively, received from the salvage of equipment on one fully depleted
well and $316 and $232, respectively, from equipment salvage on active
properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $65,670, of which $657 was distributed to the managing general partner and
$65,013 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $45,111, of which $451 was distributed to the
managing general partner and $44,660 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   737
                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   738




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 87-A Conv., Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 87-A Conv., Ltd. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 87-A Conv.,
Ltd. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   739



                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31






                                                    2000            1999
                                                 -----------    -----------
              ASSETS
              ------
                                                          
Current assets:
  Cash                                           $    42,044    $    53,265
  Accounts receivable - oil and gas sales             58,386         34,510
                                                 -----------    -----------

        Total current assets                         100,430         87,775
                                                 -----------    -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method             2,703,338      2,701,261
Accumulated depletion                             (2,357,166)    (2,326,550)
                                                 -----------    -----------

        Net oil and gas properties                   346,172        374,711
                                                 -----------    -----------

                                                 $   446,602    $   462,486
                                                 ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                   $     5,133    $     6,175

Partners' capital:
  Managing general partner                             4,417          4,565
  Limited partners (3,856 interests)                 437,052        451,746
                                                 -----------    -----------

                                                     441,469        456,311
                                                 -----------    -----------

                                                 $   446,602    $   462,486
                                                 ===========    ===========














   The accompanying notes are an integral part of these financial statements.



                                       3
   740



                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31





                                                        2000         1999         1998
                                                      --------     ---------    ---------
                                                                        
Revenues:
  Oil and gas                                          $ 380,908   $ 234,259   $ 194,541
  Interest                                                 3,744       2,131       2,599
  Gain on disposition of assets                              857       1,184         102
                                                       ---------   ---------   ---------

                                                         385,509     237,574     197,242
                                                       ---------   ---------   ---------

Costs and expenses:
  Oil and gas production                                 150,075     126,927     143,008
  General and administrative                              11,235       6,978       5,727
  Impairment of oil and gas properties                     5,726          --      63,814
  Depletion                                               24,890      35,270      83,255
                                                       ---------   ---------   ---------

                                                         191,926     169,175     295,804
                                                       ---------   ---------   ---------

Net income (loss)                                      $ 193,583   $  68,399   $ (98,562)
                                                       =========   =========   =========

Allocation of net income (loss):
  Managing general partner                             $   1,936   $     684   $    (986)
                                                       =========   =========   =========

  Limited partners                                     $ 191,647   $  67,715   $ (97,576)
                                                       =========   =========   =========

Net income (loss) per limited partnership interest     $   49.70   $   17.56   $  (25.30)
                                                       =========   =========   =========



















   The accompanying notes are an integral part of these financial statements.



                                       4
   741



                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                          Managing
                                           general     Limited
                                           partner     partners      Total
                                         ----------   ---------    ---------
                                                          
Partners' capital at January 1, 1998     $   6,329    $ 626,350    $ 632,679

    Distributions                             (761)     (75,346)     (76,107)

    Net loss                                  (986)     (97,576)     (98,562)
                                         ---------    ---------    ---------

Partners' capital at December 31, 1998       4,582      453,428      458,010

    Distributions                             (701)     (69,397)     (70,098)

    Net income                                 684       67,715       68,399
                                         ---------    ---------    ---------

Partners' capital at December 31, 1999       4,565      451,746      456,311

    Distributions                           (2,084)    (206,341)    (208,425)

    Net income                               1,936      191,647      193,583
                                         ---------    ---------    ---------

Partners' capital at December 31, 2000   $   4,417    $ 437,052    $ 441,469
                                         =========    =========    =========





















   The accompanying notes are an integral part of these financial statements.


                                       5
   742


                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                         2000          1999         1998
                                                       ---------    ---------    ---------
                                                                       
Cash flows from operating activities:
   Net income (loss)                                   $ 193,583    $  68,399    $ (98,562)
   Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
        Impairment of oil and gas properties               5,726           --       63,814
        Depletion                                         24,890       35,270       83,255
        Gain on disposition of assets                       (857)      (1,184)        (102)
   Changes in assets and liabilities:
        Accounts receivable                              (23,876)     (12,786)      17,191
        Accounts payable                                  (1,042)       1,263       (2,930)
                                                       ---------    ---------    ---------

           Net cash provided by operating activities     198,424       90,962       62,666
                                                       ---------    ---------    ---------

Cash flows from investing activities:
   Additions to oil and gas properties                    (2,560)      (5,634)      (2,338)
   Proceeds from disposition of assets                     1,340        1,238        2,095
                                                       ---------    ---------    ---------

           Net cash used in investing activities          (1,220)      (4,396)        (243)
                                                       ---------    ---------    ---------

Cash flows used in financing activities:
   Cash distributions to partners                       (208,425)     (70,098)     (76,107)
                                                       ---------    ---------    ---------

Net increase (decrease) in cash                          (11,221)      16,468      (13,684)
Cash at beginning of year                                 53,265       36,797       50,481
                                                       ---------    ---------    ---------

Cash at end of year                                    $  42,044    $  53,265    $  36,797
                                                       =========    =========    =========
















   The accompanying notes are an integral part of these financial statements.



                                       6
   743



                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.        ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 87-A Conv., Ltd. (the "Partnership") was organized in
1987 as a general partnership under the laws of the State of Texas and was
converted to a Texas limited partnership in 1989. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.        SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.



                                       7
   744

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.        IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future



                                       8
   745

cash flows at a discount rate commensurate with the risks involved in the
industry. As a result, the Partnership recognized non-cash impairment provisions
of $5,726 and $63,814 related to its proved oil and gas properties during 2000
and 1998, respectively.

NOTE 4.        INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $34,055 less than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                             2000        1999        1998
                                                           --------    --------    --------
                                                                          
Net income (loss) per statements of operations            $ 193,583    $ 68,399    $(98,562)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                               21,481      31,994      77,835
Impairment of oil and gas properties for financial
  reporting purposes                                          5,726          --      63,814
Salvage income                                                   --          --       1,795
Other, net                                                     (320)       (923)      1,074
                                                           --------    --------    --------

      Net income per Federal income tax returns           $ 220,470    $ 99,470    $ 45,956
                                                           ========    ========    ========


NOTE 5.        OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                    --------     ---------      ---------
                                                                       
    Development costs                              $   2,560     $   5,634      $   2,338
                                                    ========      ========       ========


      Capitalized oil and gas properties consist of the following:



                                        2000           1999
                                        ----           ----
                                            
Proved properties:
  Property acquisition costs       $   126,683    $   126,683
  Completed wells and equipment      2,576,655      2,574,578
                                   -----------    -----------

                                     2,703,338      2,701,261
Accumulated depletion               (2,357,166)    (2,326,550)
                                   -----------    -----------

      Net oil and gas properties   $   346,172    $   374,711
                                   ===========    ===========





                                       9
   746



NOTE 6.       RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                            2000          1999           1998
                                                         ----------    ---------      ---------
                                                                             
    Payment of lease operating and supervision
      charges in accordance with standard industry
      operating agreements                               $  57,269     $  58,965      $  59,200

    Reimbursement of general and administrative
      expenses                                           $   9,809     $   4,592      $   4,507


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 87-A, Ltd. and the Partnership (the "Partnerships") are parties
to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:



                                                              Pioneer USA (1)  Partnerships (2)
                                                              --------------   ---------------
                                                                         
    Revenues:
      Proceeds from disposition of depreciable
        properties                                              9.09091%         90.90909%
      All other revenues                                       24.242425%        75.757575%

    Costs and expenses:
      Lease acquisition costs, drilling and completion
        costs and all other costs                               9.09091%         90.90909%
      Operating costs, direct costs and general and
        administrative expenses                                24.242425%        75.757575%


   (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
         at the Partnership level and 35 limited partner interests owned by
         Pioneer USA.

   (2)   The allocation between the Partnership and Parker & Parsley 87-A, Ltd.
         is  11.80396% and 88.19604%, respectively.

NOTE 7.        OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       10
   747





                                          Oil and NGLs      Gas
                                             (bbls)        (mcf)
                                          ------------  ----------
                                                 
Net proved reserves at January 1, 1998      173,242      260,824
Revisions                                   (70,303)     (79,797)
Production                                  (14,371)     (24,025)
                                           --------     --------


Net proved reserves at December 31, 1998     88,568      157,002
Revisions                                   121,459      218,318
Production                                  (13,578)     (24,503)
                                           --------     --------


Net proved reserves at December 31, 1999    196,449      350,817
Revisions                                    (1,562)     (40,268)
Production                                  (13,096)     (20,355)
                                           --------     --------

Net proved reserves at December 31, 2000    181,791      290,194
                                           ========     ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.38 per barrel of NGLs and $7.67 per mcf of gas,
discounted at 10% was approximately $1,465,000 and undiscounted was $2,903,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.





                                       11
   748



                                                            For the years ended December 31,
                                                            ------------------------------

                                                              2000       1999       1998
                                                             -------    -------    -------
                                                                     (in thousands)
                                                                          
Oil and gas producing activities:
  Future cash inflows                                        $ 6,182    $ 4,834    $   964
  Future production costs                                     (3,279)    (2,837)      (754)
                                                             -------    -------    -------

                                                               2,903      1,997        210
  10% annual discount factor                                  (1,438)      (931)       (61)
                                                             -------    -------    -------

  Standardized measure of discounted future net cash flows   $ 1,465    $ 1,066    $   149
                                                             =======    =======    =======




                                                           For the years ended December 31,
                                                         -----------------------------------
                                                           2000         1999          1998
                                                         --------     ---------     --------
                                                                   (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (231)  $      (107)  $      (52)
    Net changes in prices and production costs                663           480         (462)
    Revisions of previous quantity estimates                  (56)          878          (87)
    Accretion of discount                                     106            15           71
    Changes in production rates, timing and other             (83)         (349)         (26)
                                                         --------     ---------     --------

    Change in present value of future net revenues            399           917         (556)
                                                         --------     ---------     --------

    Balance, beginning of year                              1,066           149          705
                                                         --------     ---------     --------

    Balance, end of year                               $    1,465   $     1,066   $      149
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                           2000       1999        1998
                                           ----       ----        ----
                                                          
Plains Marketing, L.P.                      43%        40%         --
Phillips Petroleum Company                  10%        --          --
Genesis Crude Oil, L.P.                     --         --          54%
Western Gas Resources, Inc.                  4%         7%         29%
NGTS LLC                                     8%        --          --


        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and Phillips Petroleum Company were $16,353 and $3,196, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.





                                       12
   749



NOTE 9.        PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $3,856,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.



                                       13
   750

                        PARKER & PARSLEY 87-A CONV., LTD.
                          (A TEXAS LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 63% to $380,908 for 2000 as
compared to $234,259 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decrease in production. In 2000, 8,407
barrels of oil, 4,689 barrels of natural gas liquids ("NGLs") and 20,355 mcf of
gas were sold, or 16,489 barrel of oil equivalents ("BOEs"). In 1999, 8,263
barrels of oil, 5,315 barrels of NGLs and 24,503 mcf of gas were sold, or 17,662
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.40, or 73%, from
$17.06 in 1999 to $29.46 in 2000. The average price received per barrel of NGLs
increased $6.20, or 63%, from $9.81 in 1999 to $16.01 in 2000. The average price
received per mcf of gas increased 70% from $1.68 in 1999 to $2.86 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $191,926 as compared to $169,175
in 1999, an increase of $22,751, or 13%. The increase was primarily due to
increases in production costs, impairment of oil and gas properties and general
and administrative expenses ("G&A"), offset by a decline in depletion.

Gains on disposition of assets of $857 and $1,184 were due to equipment credits
received on one well during 2000 and 1999, respectively.

Production costs were $150,075 in 2000 and $126,927 in 1999, resulting in a
$23,148 increase, or 18%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
61% from $6,978 in 1999 to $11,235 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $9,809 in 2000 and $4,592 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $5,726 related to its oil and gas properties during 2000.



   751


Depletion was $24,890 in 2000 as compared to $35,270 in 1999, representing a
decrease of $10,380, or 29%. This decrease was primarily due to an 8,116 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 20% to $234,259 from
$194,541 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decrease in production. In 1999, 8,263 barrels of oil,
5,315 barrels of NGLs and 24,503 mcf of gas were sold, or 17,662 BOEs. In 1998,
9,354 barrels of oil, 5,017 barrels of NGLs and 24,025 mcf of gas were sold, or
18,375 BOEs.

The average price received per barrel of oil increased $3.84, or 29%, from
$13.22 in 1998 to $17.06 in 1999. The average price received per barrel of NGLs
increased $3.05, or 45%, from $6.76 in 1998 to $9.81 in 1999. The average price
received per mcf of gas increased 9% from $1.54 in 1998 to $1.68 in 1999.

Total costs and expenses decreased in 1999 to $169,175 as compared to $295,804
in 1998, a decrease of $126,629, or 43%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $126,927 in 1999 and $143,008 in 1998, resulting in a
$16,081 decrease, or 11%. The decrease was due to declines in well maintenance
costs, workover expenses and ad valorem taxes, offset by an increase in
production taxes due to increased oil and gas revenues.

During this period, G&A increased 22% from $5,727 in 1998 to $6,978 in 1999
primarily due to a higher allocation of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $4,592 in
1999 and $4,507 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $63,814 related to its
oil and gas properties during 1998.

Depletion was $35,270 in 1999 compared to $83,255 in 1998, representing a
decrease of $47,985, or 58%. This decrease was primarily due to an increase in
proved reserves of 71,246 barrels of oil during 1999 as a result of higher
commodity prices, a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998 and
a decline in oil production of 1,091 barrels for the period ended December 31,
1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.




   752


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $107,462 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $148,262, offset by increases in production costs paid
of $23,148, G&A expenses paid of $4,257 and working capital of $13,395. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $165,908 to oil and gas receipts,
offset by $17,646 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and workover and well maintenance
costs incurred to stimulate well production. The increase in G&A was primarily
due to higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
upgrades of equipment on active properties.

Proceeds from asset dispositions of $1,340 and $1,238 received during 2000 and
1999, respectively, were primarily due to equipment credits received on active
properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $208,425, of which $2,084 was
distributed to the managing general partner and $206,341 to the limited
partners. In 1999, cash distributions to the partners were $70,098, of which
$701 was distributed to the managing general partner and $69,397 to the limited
partners.



   753




                        PARKER & PARSLEY 87-A CONV., LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   86,783   $  380,908   $  234,259   $  194,541   $  298,836   $  351,679
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $    5,726   $       --   $   63,814   $   98,114   $   46,639
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $          $       --   $       --   $       --   $       --   $       --   $  113,535
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   43,193   $  193,583   $   68,399   $  (98,562)  $   (7,019)  $  241,359
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      432   $    1,936   $      684   $     (986)  $      (70)  $    2,413
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   42,761   $  191,647   $   67,715   $  (97,576)  $   (6,949)  $  238,946
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    11.09   $    49.70   $    17.56   $   (25.30)  $    (1.80)  $    61.97
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    11.58   $    53.51   $    18.00   $    19.54   $    42.51   $    89.89(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  462,018   $  446,602   $  462,486   $  462,922   $  640,521   $  825,116
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $29.44
     in 1996.


   754
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 87-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED         , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS         , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
87-A, Ltd. and supplements the proxy statement/prospectus dated         , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 87-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                       -1-
   755

                           PARKER & PARSLEY 87-A, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                             
Aggregate Initial Investment by the Limited Partners(a)                                         $   28,811

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                     $   38,379

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding
Pioneer USA(a), (b)                                                                             $    5,464

Merger Value per $1,000 Limited Partner Investment(b), (c)                                      $   190.81

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the             3.23 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

        -- as of March 31, 2001(c)                                                              $   110.52

        -- as of December 31, 2000(c)                                                           $   113.60

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                               $   176.69

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                 $   185.26

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)   $      177



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                       -2-
   756

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-12244-01


                           PARKER & PARSLEY 87-A, LTD.
             (Exact name of Registrant as specified in its charter)


                        Texas                                75-2185148
          ---------------------------------            ----------------------
           (State or other jurisdiction of               (I.R.S. Employer
           incorporation or organization)              Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
           (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]




   757


                           PARKER & PARSLEY 87-A, LTD.

                                TABLE OF CONTENTS




                                                                       Page
                          Part I. Financial Information
                                                                    
Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................   10

            Signatures...............................................   11




                                        2

   758



                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                            March 31,          December 31,
                                                              2001                 2000
                                                          ------------         ------------
                                                           (Unaudited)
                       ASSETS
                                                                         
Current assets:
  Cash                                                    $    301,993         $    321,340
  Accounts receivable - oil and gas sales                      455,532              435,508
                                                          ------------         ------------
          Total current assets                                 757,525              756,848
                                                          ------------         ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                      20,197,105           20,198,629
Accumulated depletion                                      (17,685,979)         (17,611,694)
                                                          ------------         ------------
          Net oil and gas properties                         2,511,126            2,586,935
                                                          ------------         ------------
                                                          $  3,268,651         $  3,343,783
                                                          ============         ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                            $     52,367         $     37,865

Partners' capital:
  Managing general partner                                      32,136               33,032
  Limited partners (28,811 interests)                        3,184,148            3,272,886
                                                          ------------         ------------
                                                             3,216,284            3,305,918
                                                          ------------         ------------
                                                          $  3,268,651         $  3,343,783
                                                          ============         ============




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   759

                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                                 Three months ended
                                                                      March 31,
                                                          --------------------------------
                                                              2001                2000
                                                          ------------        ------------
                                                                        
Revenues:
  Oil and gas                                             $    774,832        $    648,941
  Interest                                                       5,464               5,228
  Gain on disposition of assets                                  2,399               5,861
                                                          ------------        ------------
                                                               782,695             660,030
                                                          ------------        ------------
Costs and expenses:
  Oil and gas production                                       284,079             265,708
  General and administrative                                    23,245              19,468
  Depletion                                                     74,285              51,744
                                                          ------------        ------------
                                                               381,609             336,920
                                                          ------------        ------------
Net income                                                $    401,086        $    323,110
                                                          ============        ============
Allocation of net income:
  Managing general partner                                $      4,011        $      3,231
                                                          ============        ============
  Limited partners                                        $    397,075        $    319,879
                                                          ============        ============
Net income per limited partnership interest               $      13.78        $      11.10
                                                          ============        ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        4


   760



                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                        Managing
                                        general             Limited
                                        partner            partners              Total
                                      -----------         -----------         -----------

                                                                     
Balance at January 1, 2001            $    33,032         $ 3,272,886         $ 3,305,918

  Distributions                            (4,907)           (485,813)           (490,720)

  Net income                                4,011             397,075             401,086
                                      -----------         -----------         -----------

Balance at March 31, 2001             $    32,136         $ 3,184,148         $ 3,216,284
                                      ===========         ===========         ===========


         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        5

   761



                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                                  Three months ended
                                                                      March 31,
                                                          ---------------------------------
                                                              2001                 2000
                                                          ------------         ------------
                                                                         
Cash flows from operating activities:
  Net income                                              $    401,086         $    323,110
  Adjustments to reconcile net income to
    net cash provided by operating activities:
      Depletion                                                 74,285               51,744
      Gain on disposition of assets                             (2,399)              (5,861)
  Changes in assets and liabilities:
    Accounts receivable                                        (20,024)             (33,931)
    Accounts payable                                            14,502               11,341
                                                          ------------         ------------
         Net cash provided by operating activities             467,450              346,403
                                                          ------------         ------------
Cash flows from investing activities:
  Additions to oil and gas properties                             (834)              (4,560)
  Proceeds from disposition of assets                            4,757                7,591
                                                          ------------         ------------
         Net cash provided by investing activities               3,923                3,031
                                                          ------------         ------------
Cash flows used in financing activities:
  Cash distributions to partners                              (490,720)            (337,058)
                                                          ------------         ------------
Net increase (decrease) in cash                                (19,347)              12,376
Cash at beginning of period                                    321,340              339,531
                                                          ------------         ------------
Cash at end of period                                     $    301,993         $    351,907
                                                          ============         ============


         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        6

   762



                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 87-A, Ltd. (the "Partnership") is a limited partnership
organized in 1987 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 19% to $774,832 for the three
months ended March 31, 2001 as compared to $648,941 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
declines in production. For the three months ended March 31, 2001, 14,267
barrels of oil, 7,635 barrels of natural gas liquids ("NGLs") and 42,755 mcf of
gas were sold, or 29,028 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 16,334 barrels of oil, 8,851 barrels of NGLs and
40,626 mcf of gas were sold, or 31,956 BOEs.


                                        7

   763




The average price received per barrel of oil increased $.66, or 2%, from $27.18
for the three months ended March 31, 2000 to $27.84 for the same period in 2001.
The average price received per barrel of NGLs increased $3.50, or 23%, from
$15.12 for the three months ended March 31, 2000 to $18.62 for the same period
in 2001. The average price received per mcf of gas increased 215% from $1.75
during the three months ended March 31, 2000 to $5.51 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gains on disposition of assets of $2,399 and $5,861 were due to equipment
credits received on one well during the three months ended March 31, 2001 and
2000, respectively.

Costs and Expenses:

Total costs and expenses increased to $381,609 for the three months ended March
31, 2001 as compared to $336,920 for the same period ended March 31, 2000, an
increase of $44,689, or 13%. This increase was due to increases in depletion,
production costs and general and administrative expenses ("G&A").

Production costs were $284,079 for the three months ended March 31, 2001 and
$265,708 for the same period in 2000, resulting in an increase of $18,371, or
7%. The increase was primarily due to higher production taxes associated with
higher oil and gas prices and additional well maintenance costs incurred to
stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 19% from $19,468 for the three months ended March 31, 2000 to $23,245
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $74,285 for the three months ended March 31, 2001 as compared to
$51,744 for the same  period in 2000, an increase of $22,541, or 44%. The
increase was primarily due to a downward revision to one well's proved reserves,
offset by a decline in oil production of 2,067 barrels during the three months
ended March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities:

Net cash provided by operating activities increased $121,047 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $126,127 in oil and gas sales receipts
and a reduction in working capital of $17,068, offset by increases in production
costs of $18,371 and G&A expenses of $3,777. The increase in oil and gas
receipts resulted from the increase in commodity prices during 2001 which
contributed an additional $194,581 to oil and gas receipts, offset by $68,454
resulting from the decline in production during 2001 as compared to the same
period in 2000. The increase in production costs was primarily due to increased

                                        8

   764
production  taxes  associated with higher oil and gas prices and additional well
maintenance costs incurred to stimulate well production. The increase in G&A was
primarily due to an increase in the accrual for tax preparation fees.

Net Cash Provided by Investing Activities:

The Partnership's principle investing activities during the three months ended
March 31, 2001 and 2000 were related to the upgrades of oil and gas equipment on
active properties.

Proceeds from asset dispositions of $4,757 and $7,591 received during the three
months ended March 31, 2001 and 2000, respectively, were comprised of $2,399 and
$5,861, respectively, received from the salvage of equipment on one fully
depleted well and $2,358 and $1,730, respectively, from equipment salvage on
active properties.

Net Cash Used in Financing Activities:

For the three months ended March 31, 2001, cash distributions to the partners
were $490,720, of which $4,907 was distributed to the managing general partner
and $485,813 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $337,058, of which $3,371 was
distributed to the managing general partner and $333,687 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.

                                        9

   765



                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.



                                       10

   766


                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934,  the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 87-A, LTD.


                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 10, 2001                By:     /s/ Rich Dealy
                                            --------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       11

   767

                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-12244-01


                           PARKER & PARSLEY 87-A, LTD.
             (Exact name of Registrant as specified in its charter)

                   TEXAS                                      75-2185148
        -------------------------------                  ----------------------
        (State or other jurisdiction of                     (I.R.S. Employer
         incorporation or organization)                  Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS      75039
----------------------------------------------------------------  -------------
        (Address of principal executive offices)                    (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001


       Securities registered pursuant to Section 12(b) of the Act: NONE
         Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$28,636,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 28,811.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.



   768



                                     PART I

ITEM 1.        BUSINESS

Parker & Parsley 87-A, Ltd. (the "Partnership") is a limited partnership
organized in 1987 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 28,811 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000, approximately 43% and 11% was attributable to sales made
to Plains Marketing, L.P. and NGTS LLC, respectively. Pioneer USA is of the
opinion that the loss of any one purchaser would not have an adverse effect on
its ability to sell its oil, natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial



                                       2
   769


liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.      PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 96
oil and gas wells. Two wells were dry holes. Six uneconomical wells were plugged
and abandoned and 15 oil and gas wells have been sold. At December 31, 2000, 73
wells were producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.      LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.         SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                       3
   770
                                     PART II

ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                DISTRIBUTIONS

At March 8, 2001, the Partnership had 28,811 outstanding limited partnership
interests held of record by 2,148 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $1,541,726 and
$518,518, respectively, were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:




                                 2000           1999          1998             1997           1996
                             -------------  ------------   -----------     ------------    -----------
                                                                           
Operating results:
------------------
 Oil and gas sales           $   2,845,556  $  1,750,425  $   1,453,492   $   2,232,898   $  2,627,636
                              ============   ===========   ============    ============    ===========

 Gain on litigation
   settlement, net           $          -   $         -   $          -    $          -    $    848,304
                              ============   ===========   ============    ============    ===========

 Impairment of oil and gas
   properties                $      42,807  $         -   $     477,501   $     732,890   $    348,546
                              ============   ===========   ============    ============    ===========

 Net income (loss)           $   1,444,249  $    511,237  $    (736,103)  $     (49,528)  $  1,803,894
                              ============   ===========   ============    ============    ===========

 Allocation of net income
  (loss):
   Managing general partner  $     14,442   $      5,112  $      (7,361)  $        (495)  $     18,039
                              ===========    ===========   ============    ============    ===========

   Limited partners          $  1,429,807   $    506,125  $    (728,742)  $     (49,033)  $  1,785,855
                              ===========    ===========   ============    ============    ===========

 Limited partners' net income
   (loss) per limited
   partnership interest       $     49.63   $      17.57  $      (25.29)  $       (1.70) $       61.99
                              ===========    ===========   ============    ============   ============

 Limited partners' cash
   distributions per limited
   partnership interest      $       53.51  $      18.00  $       19.54   $       42.52   $      89.89(a)
                              ============   ===========   ============    ============    ===========

At year end:
------------
 Identifiable assets          $  3,343,783   $ 3,464,619  $   3,466,459   $   4,793,102   $  6,171,831
                              ============   ===========   ============    ============    ===========


---------------

(a) Including litigation settlement per limited partnership interest of $29.15
    in 1996.



                                       4
   771


ITEM 7.       MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 63% to $2,845,556 for 2000 as
compared to $1,750,425 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decrease in production. In 2000, 62,796
barrels of oil, 35,028 barrels of natural gas liquids ("NGLs") and 152,075 mcf
of gas were sold, or 123,170 barrel of oil equivalents ("BOEs"). In 1999, 61,734
barrels of oil, 39,707 barrels of NGLs and 183,099 mcf of gas were sold, or
131,958 BOEs. Due to the decline characteristics of the Partnership's oil and
gas properties, management expects a certain amount of decline in production in
the future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.40, or 73%, from
$17.06 in 1999 to $29.46 in 2000. The average price received per barrel of NGLs
increased $6.20, or 63%, from $9.81 in 1999 to $16.01 in 2000. The average price
received per mcf of gas increased 70% from $1.68 in 1999 to $2.86 in 2000. The
market price received for oil and gas has been extremely volatile in the past
decade and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gains on disposition of assets of $6,407 and $8,848 were due to equipment
credits received on one well during 2000 and 1999, respectively.

Total costs and expenses increased in 2000 to $1,435,888 compared to $1,264,233
in 1999, an increase of $171,655, or 14%. The increase resulted from increases
in production costs, the impairment of oil and gas properties and general and
administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $1,121,487 in 2000 and $948,362 in 1999, resulting in an
increase of $173,125, or 18%. This increase was primarily due to higher
production taxes associated with higher oil and gas prices and additional well
maintenance and workover costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
63% from $52,563 in 1999 to $85,559 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $73,296 in 2000 and $34,349 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   772



In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $42,807 related to its oil and gas properties during 2000.

Depletion was $186,035 in 2000 as compared to $263,308 in 1999, representing a
decrease of $77,273, or 29%. This decrease was primarily due to a 45,228 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 20% to $1,750,425 from
$1,453,492 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decrease in production. In 1999, 61,734 barrels of oil,
39,707 barrels of NGLs and 183,099 mcf of gas were sold, or 131,958 BOEs. In
1998, 69,905 barrels of oil, 37,470 barrels of NGLs and 179,494 mcf of gas were
sold, or 137,291 BOEs.

The average price received per barrel of oil increased $3.84, or 29%, from
$13.22 in 1998 to $17.06 in 1999. The average price received per barrel of NGLs
increased $3.05, or 45%, from $6.76 in 1998 to $9.81 in 1999. The average price
received per mcf of gas increased 9% from $1.54 in 1998 to $1.68 in 1999.

A gain on disposition of assets of $8,848 was recognized during 1999 from
equipment credits received on one fully depleted well. During 1998, a gain on
disposition of assets of $765 was received from the sale of equipment on one
saltwater disposal well plugged and abandoned in a prior year.

Total costs and expenses decreased in 1999 to $1,264,233 compared to $2,210,330
in 1998, a decrease of $946,097, or 43%. The decrease resulted from declines in
the impairment of oil and gas properties, depletion and production costs, offset
by an increase in G&A.

Production costs were $948,362 in 1999 and $1,068,450 in 1998, resulting in a
$120,088 decrease, or 11%. This decrease was primarily attributable to
reductions in well maintenance costs, workover expenses and ad valorem taxes,
offset by an increase in production taxes due to increased in oil and gas
revenues.

During this period, G&A increased, in aggregate, 23% from $42,787 in 1998 to
$52,563 in 1999 primarily due to a higher percentage of the managing general
partner's G&A being allocated (limited to 3% of oil and gas revenues) as a
result of increased oil and gas revenues. The Partnership paid the managing
general partner $34,349 in 1999 and $33,674 in 1998 for G&A incurred on behalf
of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $477,501 related to its
oil and gas properties during 1998.


                                       6
   773



Depletion was $263,308 in 1999 compared to $621,592 in 1998. This represented a
decrease of $358,284, or 58%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 532,499 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 8,171
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $934,385 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $1,107,108 and a decline in working capital of
$33,398, offset by increases in production costs paid of $173,125 and G&A
expenses paid of $32,996. The increase in oil and gas receipts resulted from the
increase in commodity prices during 2000 which contributed an additional
$1,239,482 to oil and gas receipts, offset by $132,374 resulting from the
decline in production during 2000. The increase in production costs was
primarily due to increased production taxes associated with higher oil and gas
prices and additional well maintenance and workover costs incurred to stimulate
well production. The increase in G&A was primarily due to higher percentage of
the managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to the
upgrades of oil and gas equipment on active properties.

Proceeds from asset dispositions of $10,011 and $9,249 received during 2000 and
1999, respectively, were from equipment credits on one well in each year.

Net Cash Used in Financing Activities



                                       7
   774


In 2000, cash distributions to the partners were $1,557,299, of which $15,573
was distributed to the managing general partner and $1,541,726 to the limited
partners. In 1999, cash distributions to the partners were $523,756, of which
$5,238 was distributed to the managing general partner and $518,518 to the
limited partners.




                                       8
   775


ITEM 8.       FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA




                          INDEX TO FINANCIAL STATEMENTS

                                                                                        Page
                                                                                  
Financial Statements of Parker & Parsley 87-A, Ltd:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15






                                       9
   776




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 87-A, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 87-A, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 87-A, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.


                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       10
   777
                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                                      2000          1999
                                                                      ----          ----
              ASSETS
              ------

                                                                           
Current assets:
  Cash                                                         $    321,340      $   339,531
  Accounts receivable - oil and gas sales                           435,508          324,832
                                                                 ----------       ----------

       Total current assets                                         756,848          664,363
                                                                 ----------       ----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                           20,198,629       20,183,108
Accumulated depletion                                           (17,611,694)     (17,382,852)
                                                                 -----------      -----------

       Net oil and gas properties                                 2,586,935        2,800,256
                                                                 ----------      -----------

                                                               $  3,343,783     $  3,464,619
                                                                ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                 $     37,865     $    45,651

Partners' capital:
  Managing general partner                                           33,032          34,163
  Limited partners (28,811 interests)                             3,272,886       3,384,805
                                                                 ----------       ---------

                                                                  3,305,918       3,418,968
                                                                -----------      ----------

                                                               $  3,343,783     $ 3,464,619
                                                                ===========      ==========



  The accompanying notes are an integral part of these financial statements.



                                       11
   778
                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                         2000           1999          1998
                                                      ------------   ----------    ------------

                                                                          
Revenues:
  Oil and gas                                          $ 2,845,556   $ 1,750,425   $ 1,453,492
  Interest                                                  28,174        16,197        19,970
  Gain on disposition of assets                              6,407         8,848           765
                                                       -----------   -----------   -----------

                                                         2,880,137     1,775,470     1,474,227
                                                       -----------   -----------   -----------

Costs and expenses:
  Oil and gas production                                 1,121,487       948,362     1,068,450
  General and administrative                                85,559        52,563        42,787
  Impairment of oil and gas properties                      42,807            --       477,501
  Depletion                                                186,035       263,308       621,592
                                                       -----------   -----------   -----------

                                                         1,435,888     1,264,233     2,210,330
                                                       -----------   -----------   -----------

Net income (loss)                                      $ 1,444,249   $   511,237   $  (736,103)
                                                       ===========   ===========   ===========

Allocation of net income (loss):
  Managing general partner                             $    14,442   $     5,112   $    (7,361)
                                                       ===========   ===========   ===========

  Limited partners                                     $ 1,429,807   $   506,125   $  (728,742)
                                                       ===========   ===========   ===========

Net income (loss) per limited partnership interest     $   49.63     $  17.57      $    (25.29)
                                                       ===========   ===========   ===========



  The accompanying notes are an integral part of these financial statements.



                                       12
   779


                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL





                                          Managing
                                           general        Limited
                                           partner        partners         Total
                                         -----------    -----------     -----------

                                                             
Partners' capital at January 1, 1998     $    47,336    $ 4,688,910    $ 4,736,246

   Distributions                              (5,686)      (562,970)      (568,656)

   Net loss                                   (7,361)      (728,742)      (736,103)
                                         -----------    -----------     -----------

Partners' capital at December 31, 1998        34,289      3,397,198      3,431,487

   Distributions                              (5,238)      (518,518)      (523,756)

   Net income                                  5,112        506,125        511,237
                                         -----------    -----------    -----------

Partners' capital at December 31, 1999        34,163      3,384,805      3,418,968

   Distributions                             (15,573)    (1,541,726)    (1,557,299)

   Net income                                 14,442      1,429,807      1,444,249
                                         -----------    -----------    -----------

Partners' capital at December 31, 2000   $    33,032    $ 3,272,886    $ 3,305,918
                                         ===========    ===========    ===========



  The accompanying notes are an integral part of these financial statements.



                                       13
   780


                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                        2000          1999             1998
                                                   ------------    -----------     -----------


                                                                         
Cash flows from operating activities:
  Net income (loss)                                 $ 1,444,249   $    511,237    $  (736,103)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties               42,807             --        477,501
      Depletion                                         186,035        263,308        621,592
      Gain on disposition of assets                      (6,407)        (8,848)          (765)
  Changes in assets and liabilities:
      Accounts receivable                              (110,676)      (162,539)       128,574
      Accounts payable                                   (7,786)        10,679        (21,884)
                                                    -----------    -----------    -----------

        Net cash provided by operating activities     1,548,222        613,837        468,915
                                                    -----------    -----------    -----------

Cash flows from investing activities:
  Additions to oil and gas properties                   (19,125)       (42,098)       (17,466)
  Proceeds from disposition of assets                    10,011          9,249         15,652
                                                    -----------    -----------    -----------

        Net cash used in investing activities            (9,114)       (32,849)        (1,814)
                                                    -----------    -----------    -----------

Cash flows used in financing activities:
  Cash distributions to partners                     (1,557,299)      (523,756)      (568,656)
                                                    -----------    -----------    -----------

Net increase (decrease) in cash                         (18,191)        57,232       (101,555)
Cash at beginning of year                               339,531        282,299        383,854
                                                    -----------    -----------    -----------

Cash at end of year                                 $   321,340    $   339,531    $   282,299
                                                    ===========    ===========    ===========



  The accompanying notes are an integral part of these financial statements.



                                       14
   781


                           PARKER & PARSLEY 87-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.      ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 87-A, Ltd. (the "Partnership") is a limited partnership
organized in 1987 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.      SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.


                                       15
   782



        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.       IMPAIRMENT OF LONG-LIVED ASSETS


        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $42,807 and $477,501
related to its proved oil and gas properties during 2000 and 1998, respectively.

NOTE 4.       INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $254,091 less than the tax basis at December 31, 2000.



                                       16
   783



        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                        2000            1999             1998
                                                     -----------     -----------     -----------

                                                                           
Net income (loss) per statements of operations      $  1,444,249    $    511,237    $  (736,103)
Intangible development costs capitalized for
  financial reporting purposes and expensed
  for tax reporting purposes                                 --              --              (6)
Depletion and depreciation provisions for tax
  reporting purposes less than amount for
  financial reporting purposes                           162,602         238,819        584,799
Impairment of oil and gas properties for financial
  reporting purposes                                      42,807              --        477,501
Salvage income                                             1,288              --         13,408
Other, net                                                (3,728)         (5,120)         6,254
                                                     -----------     -----------     -----------

      Net income per Federal income tax
         returns                                    $  1,647,218    $    744,936    $   345,853
                                                     ===========     ===========     ===========


NOTE 5.      OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:




                                                     2000           1999          1998
                                                   ---------      --------      ---------

                                                                      
      Development costs                            $  19,125     $  42,098     $   17,466
                                                    ========      ========      =========


      Capitalized oil and gas properties consist of the following:




                                                                   2000             1999
                                                               -----------       -----------
                                                                          
    Proved properties:
      Property acquisition costs                              $    946,545      $    946,545
      Completed wells and equipment                             19,252,084        19,236,563
                                                               -----------       -----------

                                                                20,198,629        20,183,108
    Accumulated depletion                                      (17,611,694)      (17,382,852)
                                                               ------------      -----------

         Net oil and gas properties                           $  2,586,935      $  2,800,256
                                                               ===========       ===========




                                       17
   784



NOTE 6.       RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                      2000          1999          1998
                                                   ---------      ---------     ---------
                                                                      
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 428,017     $ 440,563     $  442,313

    Reimbursement of general and administrative
      expenses                                     $  73,296     $  34,349     $   33,674



        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA, Parker & Parsley 87-A Conv., L.P. and the Partnership (the
"Partnerships") are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:




                                                               Pioneer
                                                                 USA (1)        Partnerships(2)
                                                              ----------        ---------------
                                                                        
    Revenues:
      Proceeds from disposition of depreciable properties      9.09091%          90.90909%
      All other revenues                                      24.242425%         75.757575%
    Costs and expenses:
      Lease acquisition costs, drilling and completion
        and all other costs                                    9.09091%          90.90909%
      Operating costs, direct costs and general and
        administrative expenses                               24.242425%         75.757575%



   (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
         at the Partnership level and 175 limited partner interests owned by
         Pioneer USA.

   (2)   The allocation between the Partnership and Parker & Parsley 87-A Conv.,
         L.P. is 88.19604% and 11.80396%, respectively.

NOTE 7.      OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       18
   785





                                          Oil and NGLs       Gas
                                             (bbls)         (mcf)
                                           ----------    ----------

                                                  
Net proved reserves at January 1, 1998      1,294,911     1,949,548
Revisions                                    (525,530)     (596,528)
Production                                   (107,375)     (179,494)
                                           ----------    ----------

Net proved reserves at December 31, 1998      662,006     1,173,526
Revisions                                     907,814     1,631,783
Production                                   (101,441)     (183,099)
                                           ----------    ----------

Net proved reserves at December 31, 1999    1,468,379     2,622,210
Revisions                                     (35,573)     (336,529)
Production                                    (97,824)     (152,075)
                                           ----------    ----------

Net proved reserves at December 31, 2000    1,334,982     2,133,606
                                           ==========    ==========




        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.83 per barrel of NGLs and $7.67 per mcf of gas,
discounted at 10% was approximately $10,856,000 and undiscounted was
$21,368,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.





                                                            For the years ended December 31,
                                                           ----------------------------------
                                                              2000         1999       1998
                                                             --------    --------    --------
                                                                      (in thousands)
                                                                            
Oil and gas producing activities:
  Future cash inflows                                        $ 45,412    $ 36,134    $  7,206
  Future production costs                                     (24,044)    (21,211)     (5,635)
                                                             --------    --------    --------

                                                               21,368      14,923       1,571
  10% annual discount factor                                  (10,512)     (6,959)       (455)
                                                             --------    --------    --------

  Standardized measure of discounted future net cash flows   $ 10,856    $  7,964    $  1,116
                                                             ========    ========    ========




                                       19
   786





                                                           For the years ended December 31,
                                                         ------------------------------------
                                                           2000         1999         1998
                                                         --------    ----------    ---------
                                                                   (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $   (1,724)  $      (802)  $     (385)
    Net changes in prices and production costs              4,989         3,587       (3,456)
    Revisions of estimated future development costs           -             -            -
    Revisions of previous quantity estimates                 (618)        6,565         (652)
    Accretion of discount                                     796           111          527
    Changes in production rates, timing and other            (551)       (2,613)        (189)
                                                         --------    ----------    ---------

    Change in present value of future net revenues          2,892         6,848       (4,155)
                                                         --------    ----------    ---------

    Balance, beginning of year                              7,964         1,116        5,271
                                                         --------    ----------    ---------

    Balance, end of year                               $   10,856   $     7,964   $    1,116
                                                        =========    ==========    =========



NOTE 8.      MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:




                                                     2000          1999           1998
                                                   --------      --------       --------
                                                                      
           Plains Marketing, L.P.                     43%           39%             -
           Genesis Crude Oil, L.P.                     -             -             54%
           Western Gas Resources, Inc.                 3%            7%            29%
           NGTS LLC                                   11%            9%             1%



        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and NGTS LLC were $122,179 and $4,335, respectively, which is included in the
caption "Accounts receivable - oil and gas sales" in the accompanying Balance
Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.


NOTE 9.      PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The general partner of the Partnership is
        Pioneer USA. Pioneer USA, the managing general partner, has the power
        and authority to manage, control and administer all Program and
        Partnership affairs. As managing general partner and operator of the
        Partnership's properties, all production expenses are incurred by
        Pioneer USA and billed to the Partnership. The majority of the
        Partnership's oil and gas revenues are received directly by the
        Partnership, however, a portion of the oil and gas revenue is initially
        received by Pioneer USA prior to being paid to the Partnership. Under
        the limited partnership agreement,



                                       20
   787



        the managing general partner pays 1% of the Partnership's acquisition,
        drilling and completion costs and 1% of its operating and general and
        administrative expenses. In return, it is allocated 1% of the
        Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $28,811,000. Pioneer USA is required to contribute amounts equal to 1%
        of initial Partnership capital less commission and offering expenses
        allocated to the limited partners and to contribute amounts necessary to
        pay costs and expenses allocated to it under the Partnership agreement
        to the extent its share of revenues does not cover such costs.

ITEM 9.       CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                AND FINANCIAL DISCLOSURE

None.



                                       21
   788


                                    PART III

ITEM 10.      DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.




                                       Age at
                                    December 31,
       Name                             2000                 Position
       ----                             ----                 --------
                                                 
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer



        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       22
   789



        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA, Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       23
   790



ITEM 11.       EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.       SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 175 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.



                                       24
   791



ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:





                                                      2000          1999          1998
                                                    --------      --------      ---------

                                                                       
    Payment of lease operating and supervision
       charges in accordance with standard
       industry operating agreements               $ 428,017     $ 440,563      $ 442,313

    Reimbursement of general and administrative
       expenses                                    $  73,296     $  34,349      $  33,674



Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.




                                       25
   792



                                     PART IV

ITEM 14.       EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31, 2000,
                 1999 and 1998

                 Statements of partners' capital for the years ended December
                 31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31, 2000,
                 1999 and 1998

                 Notes to financial statements

      2.   Financial statement schedules.

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       26
   793


                                   SIGNATURES

        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                           PARKER & PARSLEY 87-A, LTD.

Dated: March 29, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                ------------------------------
                                                Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.





                                                                       
/s/ Scott D. Sheffield              President of Pioneer USA                  March 29, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 29, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 29, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 29, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 29, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 29, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy





                                       27
   794


                          PARKER & PARSLEY 87-A, LTD.

                              INDEX TO EXHIBITS


      The following documents are incorporated by reference in response to Item
14(c):

Exhibit No.                  Description                              Page
-----------                  -----------                              ----

    4(a)         Agreement of Limited Partnership of Parker            -
                 & Parsley 87-A, Ltd. incorporated by
                 reference to Exhibit A of the Partnership's
                 Registration Statement on Form S-1
                 (Registration No. 33-16910) (hereinafter
                 called the Partnership's Registration Statement

    4(b)         Form of Subscription Agreement and Power              -
                 of Attorney incorporated by reference to
                 Exhibit D of the Partnership's Registration
                 Statement

    4(c)         Specimen Certificate of Limited Partnership           -
                 Interest incorporated by reference to Exhibit
                 D of the Partnership's Registration Statement

   10(b)         Development Program Agreement incorporated            -
                 by reference to Exhibit C of the Partnership's
                 Registration Statement





                                       28







   795




                           PARKER & PARSLEY 87-A, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  648,941   $2,845,556   $1,750,425   $1,453,492   $2,232,898   $2,627,636
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $     --   $       --   $       --   $       --   $       --   $       --   $  848,304
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
      properties                   $          $       --   $   42,807   $       --   $  477,501   $  732,890   $  348,546
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  323,110   $1,444,249   $  511,237   $ (736,103)  $  (49,528)  $1,803,894
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
   (loss):
      Managing general
         partner                   $          $    3,231   $   14,442   $    5,112   $   (7,361)  $     (495)  $   18,039
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  319,879   $1,429,807   $  506,125   $ (728,742)  $  (49,033)  $1,785,855
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
      (loss) per limited
      partnership interest         $          $    11.10   $    49.63   $    17.57   $   (25.29)  $    (1.70)  $    61.99
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
      distributions per limited
      partnership interest         $          $    11.58   $    53.51   $    18.00   $    19.54   $    42.52   $    89.89(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $3,462,012   $3,343,783   $3,464,619   $3,466,459   $4,793,102   $6,171,831
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $29.15
     in 1996.



   796


                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

         PARKER & PARSLEY 87-B, CONV., LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED        , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS        , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
87-B Conv., Ltd. and supplements the proxy statement/prospectus dated         ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 87-B Conv., Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   797


                        PARKER & PARSLEY 87-B CONV., LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                        
Aggregate Initial Investment by the Limited Partners(a)                                                    $      4,919

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                                $      6,156

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)      $        988

Merger Value per $1,000 Limited Partner Investment(b), (c)                                                 $     201.25

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                              3.56 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                        $     130.53

      --    as of December 31, 2000(c)                                                                     $     138.95

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                          $     187.44

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                            $     195.44

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)              $        173



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion must be counsel other than counsel to Pioneer USA or the partnership.
Both the designated counsel and the legal opinion must be approved by the
limited partners. Pioneer USA has retained __________ of Dallas, Texas for the
purpose of rendering this legal opinion on behalf of the limited partners to
Pioneer USA. The merger proposals include an approval of that counsel and the
form of its opinion. A copy of the opinion is attached as an exhibit to the
merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                      -2-

   798

                        PARKER & PARSLEY 87-B CONV., LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   799



                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS





                                                   March 31,     December 31,
                                                     2001            2000
                                                 ------------    ------------
                                                 (Unaudited)
                                                           
                 ASSETS

Current assets:
  Cash                                           $     57,849    $     62,552
  Accounts receivable - oil and gas sales              67,428          87,620
                                                 ------------    ------------
        Total current assets                          125,277         150,172
                                                 ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              3,221,386       3,280,150
Accumulated depletion                              (2,691,723)     (2,733,516)
                                                 ------------    ------------
        Net oil and gas properties                    529,663         546,634
                                                 ------------    ------------
                                                 $    654,940    $    696,806
                                                 ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable:
    Affiliate                                    $      5,588    $      6,423
    Other                                                 816              --
                                                 ------------    ------------
                                                        6,404           6,423
                                                 ------------    ------------
Partners' capital:
  Managing general partner                              6,471           6,889
  Limited partners (4,919 interests)                  642,065         683,494
                                                 ------------    ------------
                                                      648,536         690,383
                                                 ------------    ------------
                                                 $    654,940    $    696,806
                                                 ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   800

                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  109,348   $  111,198
  Interest                                         1,149          882
  Gain on disposition of assets                    4,013          919
                                              ----------   ----------
                                                 114,510      112,999
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                          46,813       39,867
  General and administrative                       2,843        3,336
  Depletion                                       18,159        9,450
  Abandoned property                               3,413           --
                                              ----------   ----------
                                                  71,228       52,653
                                              ----------   ----------
Net income                                    $   43,282   $   60,346
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $      433   $      604
                                              ==========   ==========
  Limited partners                            $   42,849   $   59,742
                                              ==========   ==========
Net income per limited partnership interest   $     8.71   $    12.15
                                              ==========   ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   801

                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                              Managing
                               general      Limited
                               partner      partners        Total
                             ----------    ----------    ----------
                                                
Balance at January 1, 2001   $    6,889    $  683,494    $  690,383

    Distributions                  (851)      (84,278)      (85,129)

    Net income                      433        42,849        43,282
                             ----------    ----------    ----------

Balance at March 31, 2001    $    6,471    $  642,065    $  648,536
                             ==========    ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   802

                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                       Three months ended
                                                            March 31,
                                                     ------------------------
                                                        2001          2000
                                                     ----------    ----------
                                                             
Cash flows from operating activities:
  Net income                                         $   43,282    $   60,346
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         18,159         9,450
       Gain on disposition of assets                     (4,013)         (919)
  Changes in assets and liabilities:
       Accounts receivable                               20,192       (15,550)
       Accounts payable                                   3,618         2,168
                                                     ----------    ----------
         Net cash provided by operating activities       81,238        55,495
                                                     ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                    (1,188)         (598)
  Proceeds from disposition of assets                       376           919
                                                     ----------    ----------
         Net cash provided by (used in) investing
           activities                                      (812)          321
                                                     ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                        (85,129)      (50,010)
                                                     ----------    ----------
Net increase (decrease) in cash                          (4,703)        5,806
Cash at beginning of period                              62,552        71,344
                                                     ----------    ----------
Cash at end of period                                $   57,849    $   77,150
                                                     ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   803

                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.  Organization and nature of operations

Parker & Parsley 87-B Conv., Ltd. (the "Partnership") was organized in 1987 as a
general  partnership under the laws of the State of Texas and was converted to a
Texas limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues decreased 2% to $109,348 for the three
months ended March 31, 2001 as compared to $111,198 for the same period in 2000.
The decrease in revenues resulted from a decrease in production, offset by
higher average prices received. For the three months ended March 31, 2001, 2,438
barrels of oil, 729 barrels of natural gas liquids ("NGLs") and 4,549 mcf of gas
were sold, or 3,925 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 2,793 barrels of oil, 1,487 barrels of NGLs and 6,437 mcf
of gas were sold, or 5,353 BOEs.

The average price received per barrel of oil decreased slightly from $27.69 for
the three months ended March 31, 2000 to $27.55 for the same period in 2001. The
average price received per barrel of NGLs increased $3.74, or 25%, from $15.18



                                        6
   804

for the three months ended March 31, 2000 to $18.92 for the same period in 2001.
The average price received per mcf of gas increased 257% from $1.75 during the
three months ended March 31, 2000 to $6.24 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Gain on disposition of assets of $4,013 was received during the three months
ended March 31, 2001 of which $3,637 was from disposal of equipment on one well
plugged and abandoned during the current period and $376 was from equipment
credits received on one fully depleted well. Expenses to plug and abandon this
well were $3,413. For the three months ended March 31, 2000, $919 was recognized
due to credits received from the disposal of oil and gas equipment on one fully
depleted well.

Costs and Expenses:

Total costs and expenses increased to $71,228 for the three months ended March
31, 2001 as compared to $52,653 for the same period in 2000, an increase of
$18,575, or 35%. This increase was due to increases in depletion, production
costs and abandoned property costs, offset by a decline in general and
administrative expenses ("G&A").

Production costs were $46,813 for the three months ended March 31, 2001 and
$39,867 for the same period in 2000 resulting in a $6,946 increase, or 17%. This
increase was primarily due to additional well maintenance costs incurred to
stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
decreased 15% from $3,336 for the three months ended March 31, 2000 to $2,843
for the same period in 2001. The decline was due to less G&A being allocated
(limited to 3% of oil and gas revenues) due to lower oil and gas revenues for
the three months ended March 31, 2001 as compared to the same period in 2000,
offset by an increase in the accrual for tax preparation fees.

Depletion was $18,159 for the three months ended March 31, 2001 compared to
$9,450 for the same period in 2000, an increase of $8,709, or 92%. This increase
was primarily due to a downward revision to proved reserves on one well, offset
by a decline in oil production of 355 barrels during the three months ended
March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $25,743 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to reductions of $37,192 in working capital and $493 in G&A
expenses, offset by a decline in oil and gas sales receipts of $1,583 and
increases in production costs of $6,946 and abandoned property costs of $3,413.
The G&A decline was primarily due to less G&A being allocated (limited to 3% of



                                        7
   805

oil and gas revenues) due to less oil and gas revenues during the three months
ended March 31, 2001 as compared to the same period in 2000, offset by an
increase in the accrual of tax preparation fees. The increase in production
costs was primarily due to increased well maintenance costs incurred to
stimulate well production. The decline in oil and gas receipts resulted from a
decline in production of $34,583, offset by $36,166 resulting from higher
average prices received. The increase in abandoned property costs was due to the
plugging and abandonment of one uneconomical well.

Net Cash Provided by (Used in) Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's principle
investing activities included expenditures related to equipment upgrades on
active oil and gas properties.

Proceeds from salvage income of $376 and $919 were recognized during the three
months ended March 31, 2001 and 2000, respectively, on one fully depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $85,129, of which $851 was distributed to the managing general partner and
$84,278 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $50,010, of which $500 was distributed to the
managing general partner and $49,510 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   806
                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   807






                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 87-B Conv., Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 87-B Conv., Ltd. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 87-B Conv.,
Ltd. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   808



                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                      2000         1999
                                                      ----         ----
              ASSETS
              ------
                                                         
Current assets:
  Cash                                           $    62,552    $    71,344
  Accounts receivable - oil and gas sales             87,620         36,226
                                                 -----------    -----------

       Total current assets                          150,172        107,570
                                                 -----------    -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method             3,280,150      3,277,595
Accumulated depletion                             (2,733,516)    (2,675,751)
                                                 -----------    -----------

       Net oil and gas properties                    546,634        601,844
                                                 -----------    -----------

                                                 $   696,806    $   709,414
                                                 ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                   $     6,423    $     7,274

Partners' capital:
  Managing general partner                             6,889          7,006
  Limited partners (4,919 interests)                 683,494        695,134
                                                 -----------    -----------

                                                     690,383        702,140
                                                 -----------    -----------

                                                 $   696,806    $   709,414
                                                 ===========    ===========
















   The accompanying notes are an integral part of these financial statements.



                                       3
   809

                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                        2000          1999         1998
                                                       ---------   ---------   ---------
                                                                      
Revenues:
  Oil and gas                                          $ 469,502   $ 278,326   $ 236,434
  Interest                                                 5,144       3,117       3,558
  Gain on disposition of assets                            1,005          --       3,419
                                                       ---------   ---------   ---------

                                                         475,651     281,443     243,411
                                                       ---------   ---------   ---------

Costs and expenses:
  Oil and gas production                                 172,228     155,029     146,967
  General and administrative                              13,873       8,214       7,093
  Impairment of oil and gas properties                    21,231          --      48,745
  Depletion                                               36,534      49,790     120,823
  Abandoned property                                          --          --         965
                                                       ---------   ---------   ---------

                                                         243,866     213,033     324,593
                                                       ---------   ---------   ---------

Net income (loss)                                      $ 231,785   $  68,410   $ (81,182)
                                                       =========   =========   =========

Allocation of net income (loss):
  Managing general partner                             $   2,318   $     684   $    (812)
                                                       =========   =========   =========

  Limited partners                                     $ 229,467   $  67,726   $ (80,370)
                                                       =========   =========   =========

Net income (loss) per limited partnership interest     $   46.65   $   13.77   $  (16.34)
                                                       =========   =========   =========


















   The accompanying notes are an integral part of these financial statements.

                                       4
   810


                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                         Managing
                                          general     Limited
                                          partner     partners       Total
                                         ---------    ---------    ---------
                                                         
Partners' capital at January 1, 1998     $   9,098    $ 902,134    $ 911,232

    Distributions                           (1,056)    (104,488)    (105,544)

    Net loss                                  (812)     (80,370)     (81,182)
                                         ---------    ---------    ---------

Partners' capital at December 31, 1998       7,230      717,276      724,506

    Distributions                             (908)     (89,868)     (90,776)

    Net income                                 684       67,726       68,410
                                         ---------    ---------    ---------

Partners' capital at December 31, 1999       7,006      695,134      702,140

    Distributions                           (2,435)    (241,107)    (243,542)

    Net income                               2,318      229,467      231,785
                                         ---------    ---------    ---------

Partners' capital at December 31, 2000   $   6,889    $ 683,494    $ 690,383
                                         =========    =========    =========





















   The accompanying notes are an integral part of these financial statements.



                                       5
   811


                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                        2000         1999         1998
                                                     ---------    ---------    ---------
                                                                      
Cash flows from operating activities:
  Net income (loss)                                  $ 231,785    $  68,410    $ (81,182)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
       Impairment of oil and gas properties             21,231           --       48,745
       Depletion                                        36,534       49,790      120,823
       Gain on disposition of assets                    (1,005)          --       (3,419)
  Changes in assets and liabilities:
       Accounts receivable                             (51,394)      (7,809)      15,837
       Accounts payable                                   (851)       2,071       (4,734)
                                                     ---------    ---------    ---------

         Net cash provided by operating activities     236,300      112,462       96,070
                                                     ---------    ---------    ---------

Cash flows from investing activities:
  Additions to oil and gas properties                   (2,609)      (4,857)      (5,631)
  Proceeds from disposition of assets                    1,059        1,226        3,419
                                                     ---------    ---------    ---------

         Net cash used in investing activities          (1,550)      (3,631)      (2,212)
                                                     ---------    ---------    ---------

Cash flows used in financing activities:
  Cash distributions to partners                      (243,542)     (90,776)    (105,544)
                                                     ---------    ---------    ---------

Net increase (decrease) in cash                         (8,792)      18,055      (11,686)
Cash at beginning of year                               71,344       53,289       64,975
                                                     ---------    ---------    ---------

Cash at end of year                                  $  62,552    $  71,344    $  53,289
                                                     =========    =========    =========
















   The accompanying notes are an integral part of these financial statements.

                                       6
   812


                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.        ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 87-B Conv., Ltd. (the "Partnership") was organized in
1987 as a general partnership under the laws of the State of Texas and was
converted to a Texas limited partnership in 1989. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.        SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   813

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.        IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $21,231 and $48,745
related to its proved oil and gas properties during 2000 and 1998, respectively.



                                       8
   814

NOTE 4.        INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $63,837 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                          2000          1999         1998
                                                          ---------   ---------   ---------
                                                                         
Net income (loss) per statements of operations            $ 231,785   $ 68,410    $(81,182)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                               33,614      47,165     116,988
Impairment of oil and gas properties for financial
  reporting purposes                                         21,231          --      48,745
Other, net                                                     (643)     (5,995)     (1,248)
                                                          ---------   ---------   ---------

       Net income per Federal income tax returns          $ 285,987   $ 109,580   $  83,303
                                                          =========   =========   =========



NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999          1998
                                                    --------     ---------      ---------
                                                                       
      Development costs                            $   2,609     $   4,857      $   5,631
                                                    ========      ========       ========



      Capitalized oil and gas properties consist of the following:



                                                                      2000           1999
                                                                   ---------      ---------
                                                                          
    Proved properties:
      Property acquisition costs                                  $  135,396     $  135,396
      Completed wells and equipment                                3,144,754      3,142,199
                                                                   ---------      ---------

                                                                   3,280,150       3,277,595
    Accumulated depletion                                         (2,733,516)     (2,675,751)
                                                                   ----------     ----------

           Net oil and gas properties                             $  546,634     $   601,844
                                                                  ==========      ==========



                                       9
   815



NOTE 6.    RELATED PARTY TRANSACTIONS

    Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                 2000        1999     1998
                                                -------    -------  --------
                                                            
Payment of lease operating and supervision
  charges in accordance with standard industry
  operating agreements                           $74,535   $73,744   $71,600

Reimbursement of general and administrative
  expenses                                       $12,385   $ 5,720   $ 5,800


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 87-B, Ltd. and the Partnership (the "Partnerships") are parties
to the Program agreement.

    The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                             Pioneer USA (1)   Partnerships (2)
                                                             --------------    ----------------
                                                                         
    Revenues:
      Proceeds from disposition of depreciable
        properties                                              9.09091%          90.90909%
      All other revenues                                       24.242425%         75.757575%

    Costs and expenses:
      Lease acquisition costs, drilling and completion
        costs and all other costs                               9.09091%          90.90909%
      Operating costs, direct costs and general and
        administrative expenses                                24.242425%         75.757575%


      (1)  Excludes Pioneer USA's 1% general partner ownership which is
           allocated at the Partnership level and 10 limited partner interests
           owned by Pioneer USA.

      (2)  The allocation between the Partnership and Parker & Parsley 87-B,
           Ltd. is 19.66971% and 80.33029%, respectively.

NOTE 7.        OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.






                                         Oil and NGLs      Gas
                                            (bbls)        (mcf)
                                           --------    --------
                                                
Net proved reserves at January 1, 1998      230,505     316,120
Revisions                                   (76,948)    (70,310)
Production                                  (17,879)    (25,477)
                                           --------    --------


Net proved reserves at December 31, 1998    135,678     220,333
Revisions                                   155,187     272,717
Production                                  (16,758)    (24,436)
                                           --------    --------


Net proved reserves at December 31, 1999    274,107     468,614
Revisions                                    (9,351)    (76,076)
Production                                  (16,015)    (23,682)
                                           --------    --------


Net proved reserves at December 31, 2000    248,741     368,856
                                           ========    ========



                                       10
   816


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.26 per barrel of NGLs and $7.62 per mcf of gas,
discounted at 10% was approximately $1,851,000 and undiscounted was $3,947,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                            For the years ended December 31,
                                                           ----------------------------------
                                                             2000         1999       1998
                                                             ----         ----       ----
                                                                   (in thousands)
                                                                           
Oil and gas producing activities:
  Future cash inflows                                        $ 8,237    $ 6,760    $ 1,480
  Future production costs                                     (4,290)    (3,786)    (1,130)
                                                             -------    -------    -------

                                                               3,947      2,974        350
  10% annual discount factor                                  (2,096)    (1,454)      (110)
                                                             -------    -------    -------

  Standardized measure of discounted future net cash flows   $ 1,851    $ 1,520    $   240
                                                             =======    =======    =======


                                       11
   817



                                                           For the years ended December 31,
                                                         ------------------------------------
                                                             2000         1999        1998
                                                             ----         ----       ----
                                                                    (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (297)  $      (123)  $      (89)
    Net changes in prices and production costs                795           742         (585)
    Revisions of previous quantity estimates                 (143)        1,162         (100)
    Accretion of discount                                     152            24           94
    Changes in production rates, timing and other            (176)         (525)         (21)
                                                         --------     ---------     --------

    Change in present value of future net revenues            331         1,280         (701)
                                                         --------     ---------     --------

    Balance, beginning of year                              1,520           240          941
                                                         --------     ---------     --------

    Balance, end of year                               $    1,851   $     1,520   $      240
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

  The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:



                                                         2000         1999          1998
                                                       --------     --------      --------
                                                                
              Plains Marketing, L.P.                      49%          50%            -
              Genesis Crude Oil, L.P.                      2%           1%           57%
              Western Gas Resources, Inc.                  4%           6%           26%
              Phillips Petroleum Company                  16%           -             -


        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and Phillips Petroleum Company were $23,391 and $10,443, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.       PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:


        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.



                                       12
   818

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $4,919,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.



                                       13
   819

                        PARKER & PARSLEY 87-B CONV., LTD.
                          (A TEXAS LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 69% to $469,502 for 2000 as
compared to $278,326 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 10,352
barrels of oil, 5,663 barrels of natural gas liquids ("NGLs") and 23,682 mcf of
gas were sold, or 19,962 barrel of oil equivalents ("BOEs"). In 1999, 10,784
barrels of oil, 5,974 barrels of NGLs and 24,436 mcf of gas were sold, or 20,831
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.60, or 75%, from
$16.71 in 1999 to $29.31 in 2000. The average price received per barrel of NGLs
increased $7.17, or 74%, from $9.73 in 1999 to $16.90 in 2000. The average price
received per mcf of gas increased 82% from $1.64 in 1999 to $2.98 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $1,005, recognized during 2000, was
attributable to credits received from the disposal of oil and gas equipment on
one fully depleted well.

Total costs and expenses increased in 2000 to $243,866 as compared to $213,033
in 1999, an increase of $30,833, or 14%. The increase was primarily due to the
impairment of oil and gas properties and increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $172,228 in 2000 and $155,029 in 1999, resulting in a
$17,199 increase, or 11%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production, offset by a decline in workover
expenses.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
69% from $8,214 in 1999 to $13,873 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $12,385 in 2000 and $5,720 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $21,231 related to its oil and gas properties during 2000.

Depletion was $36,534 in 2000 as compared to $49,790 in 1999, representing a
decrease of $13,256, or 27%. This decrease was primarily due to a 2,194 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity

   820

prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 18% to $278,326 from
$236,434 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 10,784 barrels of oil,
5,974 barrels of NGLs and 24,436 mcf of gas were sold, or 20,831 BOEs. In 1998,
12,040 barrels of oil, 5,839 barrels of NGLs and 25,477 mcf of gas were sold, or
22,125 BOEs.

The average price received per barrel of oil increased $3.54, or 27%, from
$13.17 in 1998 to $16.71 in 1999. The average price received per barrel of NGLs
increased $2.91, or 43%, from $6.82 in 1998 to $9.73 in 1999. The average price
received per mcf of gas increased 10% from $1.49 in 1998 to $1.64 in 1999.

A gain on disposition of assets of $3,419 was recognized during 1998 from the
sale of oil and gas equipment on one well abandoned in a prior year. Abandoned
property costs of $965 in 1998 were related to this abandonment.

Total costs and expenses decreased in 1999 to $213,033 as compared to $324,593
in 1998, a decrease of $111,560, or 34%. The decrease was primarily due to
declines in depletion, the impairment of oil and gas properties and abandoned
property costs, offset by increases in production costs and G&A.

Production costs were $155,029 in 1999 and $146,967 in 1998, resulting in an
$8,062 increase, or 5%. The increase was due to increases in well maintenance
costs and workover costs incurred to stimulate well production, offset by a
decline in ad valorem taxes.

During this period, G&A increased 16% from $7,093 in 1998 to $8,214 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $5,720 in
1999 and $5,800 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $48,745 related to its
oil and gas properties during 1998.

Depletion was $49,790 in 1999 compared to $120,823 in 1998, representing a
decrease of $71,033, or 59%. This decrease was the result of a 92,485 barrels of
oil increase in proved reserves during 1999 as a result of higher commodity
prices, a reduction in the Partnership's net depletable basis from charges taken
in accordance with SFAS 121 during the fourth quarter of 1998 and a decline in
oil production of 1,256 barrels for the period ended December 31, 1999 compared
to the same period in 1998.

Petroleum Industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.




   821


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $123,838 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $193,203, offset by increases in production costs paid
of $17,199, G&A expenses paid of $5,659 and working capital of $46,507. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $213,360 to oil and gas receipts,
offset by $20,157 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs
incurred to stimulate well production, offset by a decline in workover expense.
The increase in G&A was primarily due to higher percentage of the managing
general partner's G&A being allocated (limited to 3% of oil and gas revenues) as
a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were
related to expenditures for oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $1,059 were comprised of $1,005 received
from salvage income on one fully depleted well and $54 from equipment credits
received on one active well. Proceeds of $1,226 received during 1999 were from
equipment credits received on one temporarily abandoned well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $243,542, of which $2,435 was
distributed to the managing general partner and $241,107 to the limited
partners. In 1999, cash distributions to the partners were $90,776, of which
$908 was distributed to the managing general partner and $89,868 to the limited
partners.




   822



                        PARKER & PARSLEY 87-B CONV., LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  111,198   $  469,502   $  278,326   $  236,434   $  345,942   $  422,550
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   21,231   $       --   $   48,745   $  188,163   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $          $       --   $       --   $       --   $       --   $       --   $  144,643
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   60,346   $  231,785   $   68,410   $  (81,182)  $  (85,292)  $  293,575
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      604   $    2,318   $      684   $     (812)  $     (853)  $    2,936
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   59,742   $  229,467   $   67,726   $  (80,370)  $  (84,439)  $  290,639
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    12.15   $    46.65   $    13.77   $   (16.34)  $   (17.17)  $    59.08
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    10.07   $    49.02   $    18.27   $    21.24   $    35.81   $    87.22(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  721,918   $  696,806   $  709,414   $  729,709   $  921,169   $1,202,384
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $29.40
     in 1996.



   823

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 87-B, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED     , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS     , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
87-B, Ltd. and supplements the proxy statement/prospectus dated       , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 87-B, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   824

                           PARKER & PARSLEY 87-B, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $  20,089

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $  25,142

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   4,036
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  201.38

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.57 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  130.69

        --        as of December 31, 2000  (c)                                                 $  139.11

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  187.57

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  195.57

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     173
(c), (f)



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as any
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                      -2-

   825

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-12244-02


                           PARKER & PARSLEY 87-B, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                                  75-2185706
          ----------------------------------            ---------------------
           (State or other jurisdiction of                 (I.R.S. Employer
           incorporation or organization)               Identification Number)


 1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas     75039
 ----------------------------------------------------------------   ----------
             (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                 Yes [x] No [ ]






   826



                           PARKER & PARSLEY 87-B, LTD.

                                TABLE OF CONTENTS





                                                                        Page
                                                                  
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
              December 31, 2000.......................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000...........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001....................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000...........................    6

            Notes to Financial Statements.............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K..........................   10

            Signatures................................................   11




                                        2

   827



                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                          March 31,        December 31,
                                                            2001               2000
                                                        ------------       ------------
                                                         (Unaudited)
                                                                     
                      ASSETS

Current assets:
  Cash                                                  $    238,842       $    257,845
  Accounts receivable - oil and gas sales                    275,384            357,836
                                                        ------------       ------------
           Total current assets                              514,226            615,681
                                                        ------------       ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                    13,156,014         13,396,004
Accumulated depletion                                    (10,992,258)       (11,162,910)
                                                        ------------       ------------
           Net oil and gas properties                      2,163,756          2,233,094
                                                        ------------       ------------
                                                        $  2,677,982       $  2,848,775
                                                        ============       ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable:
     Affiliate                                          $     22,825       $     25,998
     Other                                                     3,332                 --
                                                        ------------       ------------
                                                              26,157             25,998
                                                        ------------       ------------
Partners' capital:
  Managing general partner                                    26,446             28,156
  Limited partners (20,089 interests)                      2,625,379          2,794,621
                                                        ------------       ------------
                                                           2,651,825          2,822,777
                                                        ------------       ------------
                                                        $  2,677,982       $  2,848,775
                                                        ============       ============



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   828



                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)






                                                           Three months ended
                                                                 March 31,
                                                          ----------------------
                                                            2001          2000
                                                          --------      --------
                                                               
Revenues:
  Oil and gas                                             $446,606      $453,944
  Interest                                                   4,670         3,686
  Gain on disposition of assets                             16,389         3,753
                                                          --------      --------
                                                           467,665       461,383
                                                          --------      --------
Costs and expenses:
  Oil and gas production                                   191,209       162,841
  General and administrative                                11,612        13,618
  Depletion                                                 74,190        38,551
  Abandoned property                                        13,935            --
                                                          --------      --------
                                                           290,946       215,010
                                                          --------      --------
Net income                                                $176,719      $246,373
                                                          ========      ========
Allocation of net income:
  Managing general partner                                $  1,767      $  2,464
                                                          ========      ========
  Limited partners                                        $174,952      $243,909
                                                          ========      ========
Net income per limited partnership interest               $   8.71      $  12.14
                                                          ========      ========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   829



                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)







                                 Managing
                                  general          Limited
                                  partner          partners            Total
                                -----------       -----------       -----------
                                                           
Balance at January 1, 2001      $    28,156       $ 2,794,621       $ 2,822,777

   Distributions                     (3,477)         (344,194)         (347,671)

   Net income                         1,767           174,952           176,719
                                -----------       -----------       -----------

Balance at March 31, 2001       $    26,446       $ 2,625,379       $ 2,651,825
                                ===========       ===========       ===========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        5

   830



                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                             Three months ended
                                                                  March 31,
                                                          -------------------------
                                                            2001             2000
                                                          ---------       ---------
                                                               
Cash flows from operating activities:
   Net income                                             $ 176,719       $ 246,373
   Adjustments to reconcile net income to
     net cash provided by operating activities:
        Depletion                                            74,190          38,551
        Gain on disposition of assets                       (16,389)         (3,753)
   Changes in assets and liabilities:
     Accounts receivable                                     82,452         (71,505)
     Accounts payable                                        15,012           9,079
                                                          ---------       ---------
           Net cash provided by operating activities        331,984         218,745
                                                          ---------       ---------
Cash flows from investing activities:
   Additions to oil and gas properties                       (4,852)         (2,443)
   Proceeds from disposition of assets                        1,536           3,753
                                                          ---------       ---------
           Net cash provided by (used in) investing
             activities                                      (3,316)          1,310
                                                          ---------       ---------
Cash flows used in financing activities:
   Cash distributions to partners                          (347,671)       (204,239)
                                                          ---------       ---------
Net increase (decrease) in cash                             (19,003)         15,816
Cash at beginning of period                                 257,845         262,756
                                                          ---------       ---------
Cash at end of period                                     $ 238,842       $ 278,572
                                                          =========       =========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   831



                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 87-B, Ltd. (the "Partnership") is a limited partnership
organized in 1987 under the laws of the State of Texas.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition and
            Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues decreased 2% to $446,606 for the three
months ended March 31, 2001 as compared to $453,944 for the same period in 2000.
The decrease in revenues resulted from declines in production, offset by higher
average prices received. For the three months ended March 31, 2001, 9,952
barrels of oil, 2,989 barrels of natural gas liquids ("NGLs") and 18,570 mcf of
gas were sold, or 16,036 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 11,392 barrels of oil, 6,086 barrels of NGLs and
26,331 mcf of gas were sold, or 21,867 BOEs.

                                        7

   832


The average price received per barrel of oil decreased slightly from $27.69 for
the three months ended March 31, 2000 to $27.55 for the same period in 2001. The
average price received per barrel of NGLs increased $3.74, or 25%, from $15.18
for the three months ended March 31, 2000 to $18.92 for the same period in 2001.
The average price received per mcf of gas increased 257% from $1.75 during the
three months ended March 31, 2000 to $6.24 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Gain on disposition of assets of $16,389 was received during the three months
ended March 31, 2001 of which $14,853 was from disposal of equipment on one well
plugged and abandoned during the current period and $1,536 was from equipment
credits received on one fully depleted well. Expenses to plug and abandon this
well were $13,935. For the three months ended March 31, 2000, a gain on
disposition of assets of $3,753 was recognized due to credits received from the
disposal of oil and gas equipment on one fully depleted well.

Costs and Expenses:

Total costs and expenses increased to $290,946 for the three months ended March
31, 2001 as compared to $215,010 for the same period in 2000, an increase of
$75,936, or 35%. This increase was due to increases in depletion, production
costs and abandoned property costs, offset by a decline in general and
administrative expenses ("G&A").

Production costs were $191,209 for the three months ended March 31, 2001 and
$162,841 for the same period in 2000, resulting in a $28,368 increase, or 17%.
The increase was primarily due to additional well maintenance costs incurred to
stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
decreased 15% from $13,618 for the three months ended March 31, 2000 to $11,612
for the same period in 2001. The decline was due to less G&A being allocated
(limited to 3% of oil and gas revenues) due to lower oil and gas revenues for
the three months ended March 31, 2001 as compared to the same period in 2000,
offset by an increase in the accrual of tax preparation fees.

Depletion was $74,190 for the three months ended March 31, 2001 as compared to
$38,551 for the same period in 2000, an increase of $35,639, or 92%. This
increase was primarily due to a downward revision to proved reserves on one
well, offset by a decline in oil production of 1,440 barrels during the three
months ended March 31, 2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $113,239 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to reductions of $159,890 in working capital and $2,006 in G&A expenses, offset

                                        8

   833


by a decline in oil and gas sales receipts of $6,354 and increases in production
costs of $28,368 and abandoned property costs of $13,935. The G&A decline was
primarily due to less G&A being allocated (limited to 3% of oil and gas
revenues) due to lower oil and gas revenues during the three months ended March
31, 2001 as compared to the same period in 2000, offset by an increase in the
accrual of tax preparation fees. The increase in production costs was primarily
due to additional well maintenance costs incurred to stimulate well production.
The decline in oil and gas receipts resulted from declines in production of
$146,692, offset by $140,338 resulting from higher average prices received. The
increase in abandoned property costs was due to the plugging and abandonment of
one well during the three months ended March 31, 2001.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principle investing activities for the three months ended
March 31, 2001 and 2000 were related to expenditures for oil and gas equipment
upgrades on active properties.

Proceeds from disposition of assets of $1,536 and $3,753 were recognized during
the three months ended March 31, 2001 and 2000, respectively, from equipment
credits received on fully depleted wells.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $347,671, of which $3,477 was distributed to the managing general partner
and $344,194 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $204,239, of which $2,042 was
distributed to the managing general partner and $202,197 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

                                        9

   834


----------

(1) "Item 2. Management's Discussion and Analysis of Financial Condition and
    Results of Operations" contains forward looking statements that involve
    risks and uncertainties. Accordingly, no assurances can be given that the
    actual events and results will not be materially different than the
    anticipated results described in the forward looking statements.



                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.




                                       10

   835


                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                          PARKER & PARSLEY 87-B, LTD.


                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 10, 2001                By:     /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       11
   836
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-12244-02


                           PARKER & PARSLEY 87-B, LTD.
             (Exact name of Registrant as specified in its charter)

            TEXAS                                               75-2185706
-------------------------------                           ----------------------
(State or other jurisdiction of                             (I.R.S. Employer
incorporation or organization)                            Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS        75039
----------------------------------------------------------------      ----------
         (Address of principal executive offices)                     (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$20,044,000.

       As of March 8, 2001, the number of outstanding limited partnership
                             interests was 20,089.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   837

                                     PART I

ITEM 1.  BUSINESS

Parker & Parsley 87-B, Ltd. (the "Partnership") is a limited partnership
organized in 1987 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 20,089 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 49% and 16% was attributable to sales
made to Plains Marketing, L.P. and Phillips Petroleum Company. Pioneer USA is of
the opinion that the loss of any one purchaser would not have an adverse effect
on its ability to sell its oil, natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial

                                       2
   838

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.  PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located in
Texas were acquired by the Partnership, resulting in the Partnership's
participation in the drilling of 64 oil and gas wells. At December 31, 2000, 49
wells were producing; one well was a dry hole from a previous year; five wells
have been plugged and abandoned and nine wells were sold.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.  LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.


                                       3
   839


                                     PART II


ITEM 5.  MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
          DISTRIBUTIONS

At March 8, 2001, the Partnership had 20,089 outstanding limited partnership
interests held of record by 1,468 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $984,669 and
$367,015, respectively, were made to the limited partners.

ITEM 6.  SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                2000          1999         1998          1997         1996
                             ----------    ----------    ----------    ----------   ----------
                                                                     
Operating results:
------------------
  Oil and gas sales          $1,917,791    $1,136,700    $  965,599    $1,412,905   $1,725,580
                             ==========    ==========    ==========    ==========   ==========

  Gain on litigation
   settlement, net           $      -      $     -       $      -      $     -      $  590,715
                             ==========    ==========    ==========    ==========   ==========

  Impairment of oil and
   gas properties            $   86,674    $     -       $  199,037    $  768,208   $     -
                             ==========    ==========    ==========    ==========   ==========

  Net income (loss)          $  945,927    $  279,094    $ (331,789)   $ (347,350)  $1,199,153
                             ==========    ==========    ==========    ==========   ==========

  Allocation of net income
    (loss):
   Managing general partner  $    9,459    $    2,791    $   (3,318)   $   (3,473)  $   11,992
                             ==========    ==========    ==========    ==========   ==========

   Limited partners          $  936,468    $  276,303    $ (328,471)   $ (343,877)  $1,187,161
                             ==========    ==========    ==========    ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest     $    46.62    $    13.75    $   (16.35)   $   (17.12)  $    59.10
                             ==========    ==========    ==========    ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest     $    49.02    $    18.27    $    21.24    $    35.83   $    87.23 (a)
                             ==========    ==========    ==========    ==========   ==========

At year end:
------------
  Identifiable assets        $2,848,775    $2,900,940    $2,984,346    $3,766,001   $4,914,489
                             ==========    ==========    ==========    ==========   ==========


---------------

(a) Including litigation settlement per limited partnership interest of $29.11
    in 1996.

                                       4
   840



ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
          OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 69% to $1,917,791 for 2000 as
compared to $1,136,700 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 42,280
barrels of oil, 23,121 barrels of natural gas liquids ("NGLs") and 96,740 mcf of
gas were sold, or 81,524 barrel of oil equivalents ("BOEs"). In 1999, 44,029
barrels of oil, 24,404 barrels of NGLs and 99,771 mcf of gas were sold, or
85,062 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production to
continue in the future until the Partnership's economically recoverable reserves
are fully depleted.

The average price received per barrel of oil increased $12.60, or 75%, from
$16.71 in 1999 to $29.31 in 2000. The average price received per barrel of NGLs
increased $7.17, or 74%, from $9.73 in 1999 to $16.90 in 2000. The average price
received per mcf of gas increased 82% from $1.64 in 1999 to $2.98 in 2000. The
market price received for oil and gas has been extremely volatile in the past
decade and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

A gain on disposition of assets of $4,102, recognized during 2000, was
attributable to credits received from the disposal of oil and gas equipment on
one fully depleted well.

Total costs and expenses increased in 2000 to $997,051 as compared to $870,434
in 1999, an increase of $126,617, or 15%. The increase was primarily due to the
impairment of oil and gas properties and increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $703,352 in 2000 and $633,091 in 1999, resulting in an
increase of $70,261, or 11%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate production, offset by a decline in workover
expenses.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
69% from $34,237 in 1999 to $57,746 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $50,579 in 2000 and $23,361 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated

                                       5
   841

to reflect changes in Pioneer USA's overall business activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $86,674 related to its oil and gas properties during 2000.

Depletion was $149,279 in 2000 compared to $203,106 in 1999, representing a
decrease of $53,827, or 27%. The decrease was primarily due to an 8,836 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 18% to $1,136,700 from
$965,599 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 44,029 barrels of oil,
24,404 barrels of NGLs and 99,771 mcf of gas were sold, or 85,062 BOEs. In 1998,
49,182 barrels of oil, 23,854 barrels of NGLs and 104,072 mcf of gas were sold,
or 90,381 BOEs.

The average price received per barrel of oil increased $3.54, or 27%, from
$13.17 in 1998 to $16.71 in 1999. The average price received per barrel of NGLs
increased $2.91, or 43%, from $6.82 in 1998 to $9.73 in 1999. The average price
received per mcf of gas increased 10% from $1.49 in 1998 to $1.64 in 1999.

A gain on disposition of assets of $13,965 was received during 1998 from the
sale of oil and gas equipment on one well abandoned in a prior year. Abandoned
property costs of $3,943 were incurred in 1998. These costs were attributable to
the plugging and abandonment of one uneconomical well in a prior year.

Total costs and expenses decreased in 1999 to $870,434 as compared to $1,326,204
in 1998, a decrease of $455,770, or 34%. The decrease was due to declines in
depletion, the impairment of oil and gas properties and abandoned property
costs, offset by increases in production costs and G&A.

Production costs were $633,091 in 1999 and $600,702 in 1998, resulting in a
$32,389 increase, or 5%. The increase was due to increases in well maintenance
costs and workover costs incurred to stimulate well production, offset by a
decline in ad valorem taxes.

During this period, G&A increased 18% from $28,968 in 1998 to $34,237 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $23,361 in
1999 and $23,688 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $199,037 related to its
oil and gas

                                       6
   842

properties during 1998.

Depletion was $203,106 in 1999 compared to $493,554 in 1998. This represented a
decrease of $290,448, or 59%. The decrease was the result of a combination of
factors that included an increase in proved reserves of 377,754 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 5,153
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $569,152 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $789,348, offset by increases in production costs paid
of $70,261, G&A expenses paid of $23,509 and working capital of $126,426. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $871,310 to oil and gas receipts,
offset by $81,962 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs
incurred to stimulate well production, offset by a decline in workover expenses.
The increase in G&A was primarily due to higher percentage of the managing
general partner's G&A being allocated (limited to 3% of oil and gas revenues) as
a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $4,326 and $5,007 were received during 2000
and 1999, respectively. The proceeds of $4,326 were due to $4,102 salvage income
on one fully depleted well

                                       7
   843

and the remaining $224 on equipment credits received on an active well. The
proceeds of $5,007 were due to equipment credits received on one temporarily
abandoned well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $994,615, of which $9,946 was
distributed to the managing general partner and $984,669 to the limited
partners. In 1999, cash distributions to the partners were $370,722, of which
$3,707 was distributed to the managing general partner and $367,015 to the
limited partners.




                                       8
   844


ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----

                                                                                       
Financial Statements of Parker & Parsley 87-B, Ltd:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15




                                       9
   845



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 87-B, Ltd.
 (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley 87-B, Ltd. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 87-B, Ltd. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001


                                       10
   846


                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                                   2000             1999
                                                               ------------     -----------

                                                                         
              ASSETS
              ------

Current assets:
  Cash                                                        $     257,845    $    262,756
  Accounts receivable - oil and gas sales                           357,836         179,571
                                                               ------------     -----------

       Total current assets                                         615,681         442,327
                                                               ------------     -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                           13,396,004      13,385,570
Accumulated depletion                                           (11,162,910)    (10,926,957)
                                                               ------------     -----------

       Net oil and gas properties                                 2,233,094       2,458,613
                                                               ------------     -----------

                                                              $   2,848,775    $  2,900,940
                                                               ============     ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                $      25,998    $     29,475

Partners' capital:
  Managing general partner                                           28,156          28,643
  Limited partners (20,089 interests)                             2,794,621       2,842,822
                                                               ------------     -----------

                                                                  2,822,777       2,871,465
                                                               ------------     -----------

                                                              $   2,848,775    $  2,900,940
                                                               ============     ===========


   The accompanying notes are an integral part of these financial statements.

                                       11
   847


                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                      2000          1999           1998
                                                   ----------    ----------     ----------

                                                                       
Revenues:
  Oil and gas                                      $1,917,791    $1,136,700     $  965,599
  Interest                                             21,085        12,828         14,851
  Gain on disposition of assets                         4,102           -           13,965
                                                   ----------    ----------     ----------

                                                    1,942,978     1,149,528        994,415
                                                   ----------    ----------     ----------

Costs and expenses:
  Oil and gas production                              703,352       633,091        600,702
  General and administrative                           57,746        34,237         28,968
  Impairment of oil and gas properties                 86,674           -          199,037
  Depletion                                           149,279       203,106        493,554
  Abandoned property                                      -             -            3,943
                                                   ----------    ----------     ----------

                                                      997,051       870,434      1,326,204
                                                   ----------    ----------     ----------

Net income (loss)                                  $  945,927    $  279,094     $ (331,789)
                                                   ==========    ==========     ==========

Allocation of net income (loss):
  Managing general partner                         $    9,459    $    2,791     $   (3,318)
                                                   ==========    ==========     ==========

  Limited partners                                 $  936,468    $  276,303     $ (328,471)
                                                   ==========    ==========     ==========

Net income (loss) per limited partnership
  interest                                         $    46.62    $    13.75     $   (16.35)
                                                   ==========    ==========     ==========



   The accompanying notes are an integral part of these financial statements.

                                       12
   848


                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                   Managing
                                                   general        Limited
                                                   partner        partners          Total
                                                 -----------     -----------      -----------

                                                                         
Partners' capital at January 1, 1998             $   37,187      $3,688,711       $3,725,898

    Distributions                                    (4,310)       (426,706)        (431,016)

    Net loss                                         (3,318)       (328,471)        (331,789)
                                                 -----------     -----------      -----------

Partners' capital at December 31, 1998               29,559       2,933,534        2,963,093

    Distributions                                    (3,707)       (367,015)        (370,722)

    Net income                                        2,791         276,303          279,094
                                                 -----------     -----------      -----------

Partners' capital at December 31, 1999               28,643       2,842,822        2,871,465

    Distributions                                    (9,946)       (984,669)        (994,615)

    Net income                                        9,459         936,468          945,927
                                                 -----------     -----------      -----------

Partners' capital at December 31, 2000           $   28,156      $2,794,621       $2,822,777
                                                 ===========     ===========      ===========



   The accompanying notes are an integral part of these financial statements.

                                       13
   849


                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                      2000          1999           1998
                                                   ---------     ---------      ---------

                                                                       
Cash flows from operating activities:
  Net income (loss)                                $ 945,927     $ 279,094      $(331,789)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties            86,674           -          199,037
      Depletion                                      149,279       203,106        493,554
      Gain on disposition of assets                   (4,102)          -          (13,965)
    Changes in assets and liabilities:
      Accounts receivable                           (178,265)      (63,538)        64,682
      Accounts payable                                (3,477)        8,222        (18,850)
                                                   ---------     ---------      ---------

         Net cash provided by operating activities   996,036       426,884        392,669
                                                   ---------     ---------      ---------

Cash flows from investing activities:
  Additions to oil and gas properties                (10,658)      (19,835)       (22,998)
  Proceeds from disposition of assets                  4,326         5,007         13,965
                                                   ---------     ---------      ---------

         Net cash used in investing activities        (6,332)      (14,828)        (9,033)
                                                   ---------     ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                    (994,615)     (370,722)      (431,016)
                                                   ---------     ---------      ---------

Net increase (decrease) in cash                       (4,911)       41,334        (47,380)
Cash at beginning of year                            262,756       221,422        268,802
                                                   ---------     ---------      ---------

Cash at end of year                                $ 257,845     $ 262,756      $ 221,422
                                                   =========     =========      =========



   The accompanying notes are an integral part of these financial statements.

                                       14
   850


                           PARKER & PARSLEY 87-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.  ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 87-B, Ltd. (the "Partnership") is a limited partnership
organized in 1987 under the laws of the State of Texas. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.  SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the

                                       15
   851

respective partners.

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.  IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $86,674 and $199,037
related to its proved oil and gas properties during 2000 and 1998, respectively.

NOTE 4.  INCOME TAXES

                                       16
   852

     The financial statement basis of the Partnership's net assets and
liabilities was $261,429 greater than the tax basis at December 31, 2000.

     The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                          2000           1999           1998
                                                      ----------       --------      ---------

                                                                            
Net income (loss) per statements of operations        $  945,927       $279,094      $(331,789)
Intangible development costs capitalized for
  financial reporting purposes and expensed
  for tax reporting purposes                                  --           (273)            (5)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                           137,352        192,661        477,912
Impairment of oil and gas properties for financial
  reporting purposes                                      86,674             --        199,037
Loss on sale of assets for tax reporting purposes
  greater than amounts for financial reporting
  purposes                                                    --        (25,328)            --
Other, net                                                (2,628)         2,156         (4,671)
                                                      ----------       --------      ---------

  Net income per Federal income tax returns           $1,167,325       $448,310      $ 340,484
                                                      ==========       ========      =========


NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                          2000           1999           1998
                                                      ----------       --------      ---------

                                                                            
      Development costs                               $  10,658        $  19,835     $  22,998
                                                      ==========       ========      =========


      Capitalized oil and gas properties consist of the following:



                                                                  2000              1999
                                                              -----------       -----------

                                                                         
    Proved properties:
      Property acquisition costs                             $    552,956      $    552,956
      Completed wells and equipment                            12,843,048        12,832,614
                                                              -----------       -----------

                                                               13,396,004        13,385,570
    Accumulated depletion                                     (11,162,910)      (10,926,957)
                                                              -----------       -----------

          Net oil and gas properties                         $  2,233,094      $  2,458,613
                                                              ===========       ===========



                                       17
   853


NOTE 6.       RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                          2000           1999           1998
                                                      ----------       --------      ---------

                                                                            
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                   $ 304,400        $ 301,167     $ 292,411

    Reimbursement of general and administrative
      expenses                                        $  50,579        $  23,361     $  23,688


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. In addition,
Pioneer USA, Parker & Parsley 87-B Conv., Ltd. and the Partnership (the
"Partnerships") are parties to the Program agreement.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                               Pioneer
                                                               USA (1)      Partnerships (2)
                                                              ----------    ----------------

                                                                         
  Revenues:
    Proceeds from disposition of depreciable properties        9.09091%        90.90909%
    All other revenues                                        24.242425%       75.757575%
  Costs and expenses:
    Lease acquisition costs, drilling and completion
      costs and all other costs                                9.09091%        90.90909%
    Operating costs, direct costs and general and
      administrative expenses                                 24.242425%       75.757575%


      (1)   Excludes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 45 limited partner interests
            owned by Pioneer USA.

      (2)   The allocation between the Partnership and Parker & Parsley 87-B
            Conv., Ltd. is 80.33029% and 19.66971%, respectively.

NOTE 7.  OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       18
   854




                                                              Oil and NGLs        Gas
                                                                (bbls)           (mcf)
                                                              ------------    -------------

                                                                         
    Net proved reserves at January 1, 1998                       941,555         1,291,273
    Revisions                                                   (314,311)         (287,194)
    Production                                                   (73,036)         (104,072)
                                                              -----------      ------------

    Net proved reserves at December 31, 1998                     554,208           900,007
    Revisions                                                    633,879         1,113,934
    Production                                                   (68,433)          (99,771)
                                                              -----------      ------------

    Net proved reserves at December 31, 1999                   1,119,654         1,914,170
    Revisions                                                    (38,404)         (311,039)
    Production                                                   (65,401)          (96,740)
                                                              -----------      ------------

    Net proved reserves at December 31, 2000                   1,015,849         1,506,391
                                                              ===========      ============


    As of December 31, 2000, the estimated present value of future net revenues
of proved reserves, calculated using December 31, 2000 prices of $26.64 per
barrel of oil, $13.26 per barrel of NGLs and $7.62 per mcf of gas, discounted at
10% was approximately $7,561,000 and undiscounted was $16,119,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                   For the years ended December 31,
                                                                --------------------------------------
                                                                    2000          1999         1998
                                                                ----------    ----------   ----------
                                                                            (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                           $   33,638    $   27,613   $    6,049
  Future production costs                                          (17,519)      (15,463)      (4,620)
                                                                ----------    ----------   ----------

                                                                    16,119        12,150        1,429
  10% annual discount factor                                        (8,558)       (5,940)        (449)
                                                                ----------    ----------   ----------

  Standardized measure of discounted future net cash flows      $    7,561    $   6,210    $      980
                                                                ==========    ==========   ==========


                                       19
   855



                                                           For the years ended December 31,
                                                        --------------------------------------
                                                           2000          1999         1998
                                                        ----------    ----------   ----------
                                                                    (in thousands)
                                                                          
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs          $  (1,214)   $     (504)   $    (365)
    Net changes in prices and production costs              3,247         3,033       (2,391)
    Revisions of estimated future development costs           -             -            -
    Revisions of previous quantity estimates                 (587)        4,749         (410)
    Accretion of discount                                     621            98          385
    Changes in production rates, timing and other            (716)       (2,146)         (87)
                                                        ----------   -----------   ----------

    Change in present value of future net revenues          1,351         5,230       (2,868)
                                                        ----------   -----------   ----------

    Balance, beginning of year                              6,210           980        3,848
                                                        ----------   -----------   ----------

    Balance, end of year                                $   7,561    $    6,210    $     980
                                                        ==========   ===========   ==========


NOTE 8.  MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                     ----          ----           ----

                                                                        
          Plains Marketing, L.P.                      49%           50%             -
          Genesis Crude Oil, L.P.                      2%            -             57%
          Western Gas Resources, Inc.                  4%            6%            26%
          Phillips Petroleum Company                  16%            9%             8%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and Phillips Petroleum Company were $95,526 and $42,656, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.  PARTNERSHIP AGREEMENT

       The following is a brief summary of the more significant provisions of
the limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the limited partnership agreement, the managing general partner pays
      1% of the Partnership's acquisition, drilling and completion costs and 1%
      of its operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

                                       20
   856

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of
      $20,089,000. Pioneer USA is required to contribute amounts equal to 1% of
      initial Partnership capital less commission and offering expenses
      allocated to the limited partners and to contribute amounts necessary to
      pay costs and expenses allocated to it under the Partnership agreement to
      the extent its share of revenues does not cover such costs.

ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
          FINANCIAL DISCLOSURE

None.

                                       21
   857


                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                     December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                 
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

                                       22
   858


      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.

                                       23
   859


ITEM 11. EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 45 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:

                                       24
   860




                                                     2000          1999           1998
                                                     ----          ----           ----

                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $304,400      $ 301,167      $292,411

    Reimbursement of general and administrative
      expenses                                     $ 50,579      $  23,361      $ 23,688


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.






                                       25
   861


                                     PART IV


ITEM 14. EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                  Independent Auditors' Report

                  Balance sheets as of December 31, 2000 and 1999

                  Statements of operations for the years ended December 31,
                     2000, 1999 and 1998

                  Statements of partners' capital for the years ended December
                     31, 2000, 1999 and 1998

                  Statements of cash flows for the years ended December 31,
                     2000, 1999 and 1998

                  Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.

                                       26
   862


                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                           PARKER & PARSLEY 87-B, LTD.

Dated: March 28, 2001      By:   Pioneer Natural Resources USA, Inc.
                                  Managing General Partner


                                 By: /s/ Scott D. Sheffield
                                     -----------------------------
                                     Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.


                                                                       
/s/ Scott D. Sheffield              President of Pioneer USA                  March 28, 2001
----------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 28, 2001
----------------------------        Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 28, 2001
----------------------------        Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 28, 2001
----------------------------        Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 28, 2001
----------------------------        Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 28, 2001
----------------------------        Officer of Pioneer USA
Rich Dealy


                                       27
   863


                           PARKER & PARSLEY 87-B, LTD.

                                INDEX TO EXHIBITS




      The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----

                                                                        
      4(a)                Agreement of Limited Partnership of Parker                -
                          & Parsley 87-B, Ltd. incorporated by
                          reference to Exhibit A of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-16910) (hereinafter
                          called the Partnership's Registration Statement

      4(b)                Form of Subscription Agreement and Power                  -
                          of Attorney incorporated by reference to
                          Exhibit D of the Partnership's Registration
                          Statement

      4(c)                Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit
                          D of the Partnership's Registration Statement

     10(b)                Development Program Agreement incorporated                -
                          by reference to Exhibit C of the Partnership's
                          Registration Statement







                                       28
   864



                           PARKER & PARSLEY 87-B, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  453,944   $1,917,791   $1,136,700   $  965,599   $1,412,905   $1,725,580
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $     --   $       --   $       --   $       --   $       --   $       --   $  590,715
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
      gas properties               $          $       --   $   86,674   $       --   $  199,037   $  768,208   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  246,373   $  945,927   $  279,094   $ (331,789)  $ (347,350)  $1,199,153
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
        partner                    $          $    2,464   $    9,459   $    2,791   $   (3,318)  $   (3,473)  $   11,992
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  243,909   $  936,468   $  276,303   $ (328,471)  $ (343,877)  $1,187,161
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    12.14   $    46.62   $    13.75   $   (16.35)  $   (17.12)  $    59.10
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    10.07   $    49.02   $    18.27   $    21.24   $    35.83   $    87.23(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $2,952,153   $2,848,775   $2,900,940   $2,984,346   $3,766,001   $4,914,489
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of $29.11
     in 1996.



   865
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

  PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED     , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS     , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Producing Properties 87-A, Ltd. and supplements the proxy statement/prospectus
dated        , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Producing Properties 87-A, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment

     o    Information about:


          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on From 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   866
                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                
Aggregate Initial Investment by the Limited Partners  (a)                                          $  12,213

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                      $  12,217

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer          $   2,570
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                       $  211.17

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the               3.10 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                        $   86.01

        --        as of December 31, 2000  (c)                                                     $   90.89

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                                $  194.33

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                                  $  205.08

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment  (f)                --



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Not applicable. Since this partnership purchased producing properties,
     there were no intangible drilling and development costs nor any related
     write-off for tax purposes.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   867

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-11193-1


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
             (Exact name of Registrant as specified in its charter)


                          Texas                              75-2195512
            ----------------------------------         ---------------------
             (State or other jurisdiction of              (I.R.S. Employer
             incorporation or organization)            Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
           (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]



   868

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.

                                TABLE OF CONTENTS




                                                                        Page
                                                                     

                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................   10

            Signatures...............................................   11





                                       2
   869

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,       December 31,
                                                       2001              2000
                                                   ------------      ------------
                                                    (Unaudited)
                                                               
                 ASSETS

Current assets:
  Cash                                             $    172,504      $    182,206
  Accounts receivable - oil and gas sales               255,541           296,053
                                                   ------------      ------------
        Total current assets                            428,045           478,259
                                                   ------------      ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,499,027         5,701,037
Accumulated depletion                                (4,832,692)       (5,019,550)
                                                   ------------      ------------
        Net oil and gas properties                      666,335           681,487
                                                   ------------      ------------
                                                   $  1,094,380      $  1,159,746
                                                   ============      ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $     32,069      $     37,242

Partners' capital:
  Managing general partner                               11,864            12,466
  Limited partners (24,426 interests)                 1,050,447         1,110,038
                                                   ------------      ------------
                                                      1,062,311         1,122,504
                                                   ------------      ------------
                                                   $  1,094,380      $  1,159,746
                                                   ============      ============



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                       3
   870

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                     Three months ended
                                                          March 31,
                                                -----------------------------
                                                    2001             2000
                                                ------------     ------------
                                                           
Revenues:
  Oil and gas                                   $    383,411     $    366,869
  Interest                                             3,496            2,936
  Gain on disposition of assets                       27,320           15,629
                                                ------------     ------------
                                                     414,227          385,434
                                                ------------     ------------
Costs and expenses:
  Oil and gas production                             170,185          159,161
  General and administrative                          11,502           11,006
  Depletion                                           15,152           18,149
  Abandoned property                                  12,271           12,783
                                                ------------     ------------
                                                     209,110          201,099
                                                ------------     ------------
Net income                                      $    205,117     $    184,335
                                                ============     ============
Allocation of net income:
  Managing general partner                      $      2,051     $      1,843
                                                ============     ============
  Limited partners                              $    203,066     $    182,492
                                                ============     ============
Net income per limited partnership interest     $       8.31     $       7.47
                                                ============     ============



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                       4
   871

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                 Managing
                                 general           Limited
                                 partner           partners           Total
                               ------------      ------------      ------------


                                                          
Balance at January 1, 2001     $     12,466      $  1,110,038      $  1,122,504

    Distributions                    (2,653)         (262,657)         (265,310)

    Net income                        2,051           203,066           205,117
                               ------------      ------------      ------------

Balance at March 31, 2001      $     11,864      $  1,050,447      $  1,062,311
                               ============      ============      ============



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                       5
   872

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                        Three months ended
                                                             March 31,
                                                     -------------------------
                                                        2001           2000
                                                     ----------     ----------
                                                              
Cash flows from operating activities:
  Net income                                         $  205,117     $  184,335
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         15,152         18,149
       Gain on disposition of assets                    (27,320)       (15,629)
  Changes in assets and liabilities:
       Accounts receivable                               40,512        (55,179)
       Accounts payable                                  10,630         (1,433)
                                                     ----------     ----------
         Net cash provided by operating activities      244,091        130,243
                                                     ----------     ----------
Cash flows provided by investing activities:
  Proceeds from disposition of assets                    11,517         18,129

Cash flows used in financing activities:
  Cash distributions to partners                       (265,310)      (134,767)
                                                     ----------     ----------
Net increase (decrease) in cash                          (9,702)        13,605
Cash at beginning of period                             182,206        170,538
                                                     ----------     ----------
Cash at end of period                                $  172,504     $  184,143
                                                     ==========     ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                       6
   873

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley Producing Properties 87-A, Ltd. (the "Partnership") is a
limited partnership organized in 1987 under the laws of the State of Texas.

The Partnership engages in oil and gas production in Texas and is not involved
in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 5% to $383,411 for the three
months ended March 31, 2001 as compared to $366,869 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 11,080
barrels of oil, 1,780 barrels of natural gas liquids ("NGLs") and 11,750 mcf of
gas were sold, or 14,818 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 11,876 barrels of oil, 1,997 barrels of NGLs and
9,135 mcf of gas were sold, or 15,396 BOEs.



                                       7
   874

The average price received per barrel of oil increased slightly from $27.47 for
the three months ended March 31, 2000 to $27.48 for the same period in 2001. The
average price received per barrel of NGLs increased $1.44, or 12%, from $11.93
for the three months ended March 31, 2000 to $13.37 for the same period in 2001.
The average price received per mcf of gas increased 155% from $1.84 during the
three months ended March 31, 2000 to $4.69 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Gains on disposition of assets of $27,320 and $15,629 were recognized during the
three months ended March 31, 2001 and 2000, respectively. The gain recognized
during 2001 was due to $25,956 from equipment credits on one well plugged and
abandoned in the current period and $1,364 was due to salvage income from a well
abandoned during 2000. The gain recognized during 2000 was comprised of $10,858
from equipment credits on one well plugged and abandoned in the current period
and $4,771 salvage income on a well plugged and abandoned during 1999.

Costs and Expenses:

Total costs and expenses increased to $209,110 for the three months ended March
31, 2001 as compared to $201,099 for the same period in 2000, an increase of
$8,011, or 4%. This increase was the result of higher production costs and
general and administrative expenses ("G&A"), offset by declines in depletion and
abandoned property costs.

Production costs were $170,185 for the three months ended March 31, 2001 and
$159,161 for the same period in 2000, resulting in an $11,024 increase, or 7%.
This increase was primarily due to additional well maintenance costs incurred to
stimulate well production and higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 5% from $11,006 for the three months ended March 31, 2000 to $11,502
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $15,152 for the three months ended March 31, 2001 as compared to
$18,149 for the same period in 2000, a decrease of $2,997, or 17%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices and a
reduction in the Partnership's net depletable basis from charges taken in
accordance with Statement of Financial Accounting Standards No. 121, "Accounting
for the Impairment of Long-Lived Assets and for Long-Lived Assets to be Disposed
Of" ("SFAS 121") during the fourth quarter of 2000.

Abandoned property costs of $12,271 and $12,783 were incurred on the abandonment
of one well during each period ended March 31, 2001 and 2000, respectively.



                                       8
   875

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $113,848 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $17,102 in oil and gas sales receipts
and reductions in working capital of $107,754 and abandoned property costs of
$512, offset by increases in production costs of $11,024 and G&A expenses of
$496. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2001 which contributed an additional $29,603 to oil and
gas receipts, offset by $12,501 resulting from the decline in production during
2001 as compared to the same period in 2000. The increase in production costs
was primarily due to additional well maintenance costs incurred to stimulate
well production and increased production taxes associated with higher oil and
gas prices. The increase in G&A was primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Provided  by Investing Activities

Proceeds from disposition of assets of $11,517 and $18,129 were recognized
during the three months ended March 31, 2001 and 2000, respectively. The
proceeds recognized during both periods were from equipment credits on wells
plugged and abandoned.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $265,310, of which $2,653 was distributed to the managing general partner
and $262,657 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $134,767, of which $1,348 was
distributed to the managing general partner and $133,419 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.



                                       9
   876

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)     Exhibits - none

(b)     Reports on Form 8-K - none.




                                       10
   877

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                           PARKER & PARSLEY PRODUCING
                                           PROPERTIES 87-A, LTD.


                                  By:      Pioneer Natural Resources USA, Inc.
                                            Managing General Partner



Dated:  May 14, 2001              By:      /s/ Rich Dealy
                                           -------------------------------------
                                           Rich Dealy, Vice President
                                             and Chief Accounting Officer




                                       11

   878
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-11193-1


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
             (Exact name of Registrant as specified in its charter)

            TEXAS                                               75-2195512
-------------------------------                           ----------------------
(State or other jurisdiction of                             (I.R.S. Employer
incorporation or organization)                            Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS        75039
----------------------------------------------------------------      ----------
         (Address of principal executive offices)                     (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                  LIMITED PARTNERSHIP INTERESTS ($500 PER UNIT)
                  ---------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$12,170,000.

       As of March 8, 2001, the number of outstanding limited partnership
                             interests was 24,426.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   879

                                     PART I

ITEM 1.       BUSINESS

Parker & Parsley Producing Properties 87-A, Ltd. (the "Partnership") is a
limited partnership organized in 1987 under the laws of the State of Texas. The
Partnership's managing general partner is Pioneer Natural Resources USA, Inc.
("Pioneer USA"). Pioneer USA is a wholly-owned subsidiary of Pioneer Natural
Resources Company ("Pioneer"). As of March 8, 2001, the Partnership had 24,426
limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 59%, 15% and 11% were attributable to
sales made to Plains Marketing, L.P., Phillips Petroleum Company and TEPPCO
Crude Oil LLC, respectively. Pioneer USA is of the opinion that the loss of any
one purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and

                                       2
   880

ruptures and discharges of toxic substances or gases that could expose the
Partnership to substantial liability due to pollution and other environmental
damages. Although the Partnership believes that its business operations do not
impair environmental quality and that its costs of complying with any applicable
environmental regulations are not currently significant, the Partnership cannot
predict what, if any, effect these environmental regulations may have on its
current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.      PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

The Partnership completed seven purchases of producing properties. These
acquisitions involved the purchase of working interests in 187 properties of
which 98 uneconomical oil and gas wells were plugged and abandoned and seven
wells were sold. The Partnership also participated in the drilling of two oil
and gas wells during 1988 which were completed as producers. During 1997, the
Partnership participated in the recompletion of one well in which Pioneer USA
acquired the deep rights. The Partnership already owned the shallow rights of
the well bore. At December 31, 2000, the Partnership had 85 producing oil and
gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.      LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.     SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.

                                       3
   881

                                     PART II

ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                 DISTRIBUTIONS

At March 8, 2001, the Partnership had 24,426 outstanding limited partnership
interests held of record by 1,104 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $618,681 and
$223,952, respectively, were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                   2000         1999          1998         1997         1996
                                ---------     ---------     --------     ---------    ---------

                                                                      
Operating results:
-----------------
  Oil and gas sales            $1,514,918    $  860,305   $  807,421    $1,244,727   $1,772,612
                                =========     =========    =========     =========    =========

  Gain on litigation
    settlement, net            $      -      $      -     $      -      $     -      $   19,935
                                =========     =========    =========     =========    =========

  Impairment of oil and gas
    properties                 $   59,777    $   43,412   $   37,388    $  420,264   $   39,087
                                =========     =========    =========     =========    =========

  Net income (loss)            $  601,515    $  134,700   $ (357,482)   $ (397,297)  $  984,877
                                =========     =========    =========     =========    =========

  Allocation of net income
    (loss):
    Managing general partner   $    6,015    $    1,347   $   (3,575)   $   (3,973)  $    9,849
                                =========     =========    =========     =========    =========

    Limited partners           $  595,500    $  133,353   $ (353,907)   $ (393,324)  $  975,028
                                =========     =========    =========     =========    =========

  Limited partners' net income
    (loss) per limited
    partnership interest       $    24.38    $     5.46   $   (14.49)   $   (16.10)  $    39.92
                                =========     =========    =========     =========    =========

  Limited partners' cash
    distributions per limited
    partnership interest       $    25.33    $     9.17   $     9.31    $    24.14   $    36.01 (a)
                                =========     =========    =========     =========    =========

At year end:
-----------
  Identifiable assets          $1,159,746    $1,181,827   $1,270,446    $1,871,158   $2,817,583
                                =========     =========    =========     =========    =========



---------------
(a) Including litigation settlement of $.81 per limited partnership interest in
    1996.

ITEM 7.       MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
               RESULTS OF OPERATIONS

Results of operations

                                       4
   882

2000 compared to 1999

The Partnership's oil and gas revenues increased 76% to $1,514,918 for 2000 as
compared to $860,305 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 43,390
barrels of oil, 10,266 barrels of natural gas liquids ("NGLs") and 45,872 mcf of
gas were sold, or 61,301 barrel of oil equivalents ("BOEs"). In 1999, 41,606
barrels of oil, 11,495 barrels of NGLs and 53,145 mcf of gas were sold, or
61,959 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.54, or 75%, from
$16.80 in 1999 to $29.34 in 2000. The average price received per barrel of NGLs
increased $4.80, or 66%, from $7.32 in 1999 to $12.12 in 2000. The average price
received per mcf of gas increased 75% from $1.46 in 1999 to $2.56 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $37,944 recognized during 2000 resulted from
$26,860 in salvage income received on a fully depleted well and wells plugged
and abandoned in prior years, in addition to an $11,084 gain recognized from the
abandonment of three wells during the current year. Gain on disposition of
assets of $25,173 for 1999 resulted from $17,629 in salvage income received on
the abandonment of two oil and gas wells during 1999, in addition to $7,544
salvage income received on fully depleted wells and wells plugged and abandoned
in prior years.

Total costs and expenses increased in 2000 to $967,456 as compared to $760,971
in 1999, an increase of $206,485, or 27%. The increase was due to higher
production costs, general and administrative expenses ("G&A"), the impairment of
oil and gas properties and abandoned property costs, offset by a decline in
depletion.

Production costs were $765,021 in 2000 and $555,988 in 1999, resulting in an
increase of $209,033, or 38%. The increase was primarily due to additional
workover costs and well maintenance costs incurred to stimulate production and
higher production taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
76%, from $25,809 in 1999 to $45,448 in 2000 primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $29,711 in 2000 and $1,550 in 1999
for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

                                       5
   883

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized
non-cash charges of $59,777 and $43,412 related to its oil and gas properties
during 2000 and 1999, respectively.

Depletion was $69,296 in 2000 as compared to $109,034 in 1999, representing a
decrease of $39,738, or 36%. This decrease was primarily due to a 119,706
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1999.

Abandoned property costs of $27,914 and $26,728 were incurred on the abandonment
of several properties in 2000 and 1999, respectively.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 7% to $860,305 from
$807,421 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 41,606 barrels of oil,
11,495 barrels of NGLs and 53,145 mcf of gas were sold, or 61,959 BOEs. In 1998,
51,039 barrels of oil, 13,328 barrels of NGLs and 56,240 mcf of gas were sold,
or 73,740 BOEs.

The average price received per barrel of oil increased $3.76, or 29%, from
$13.04 in 1998 to $16.80 in 1999. The average price received per barrel of NGLs
increased $1.86, or 34%, from $5.46 in 1998 to $7.32 in 1999. The average price
received per mcf of gas increased 19% from $1.23 in 1998 to $1.46 in 1999.

The $25,173 gain on disposition of assets for 1999 resulted from $17,629 in
salvage income received on the abandonment of two oil and gas wells during 1999,
in addition to $7,544 salvage income received on fully depleted wells and wells
plugged and abandoned in prior years. During 1998, the $24,040 gain on
disposition of assets resulted from $29,099 in salvage income received during
1998 on properties that were plugged and abandoned in prior years, offset by a
$5,059 loss on the abandonment of two oil and gas wells and one saltwater
disposal well.

Total costs and expenses decreased in 1999 to $760,971 as compared to $1,202,296
in 1998, a decrease of $441,325, or 37%. The decrease was due to declines in
depletion, production costs and abandoned property costs, offset by increases in
the impairment of oil and gas properties and G&A.

Production costs were $555,988 in 1999 and $682,634 in 1998, resulting in a
$126,646 decrease, or 19%. The decrease was due to reductions in well
maintenance costs and ad valorem taxes, offset by an increase in workover costs
incurred to stimulate production.

During this period, G&A increased 7%, from $24,223 in 1998 to $25,809 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and



                                       6
   884
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $1,550 in 1999 and $10,723 in 1998 for G&A
incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $43,412 and $37,388
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion was $109,034 in 1999 compared to $383,398 in 1998, representing a
decrease of $274,364, or 72%. This decrease was the result of an increase in
proved reserves of 306,417 barrels of oil during 1999 as a result of higher
commodity prices, a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998 and
a decline in oil production of 9,433 barrels for the period ended December 31,
1999 compared to the same period in 1998.

Abandoned property costs of $26,728 and $74,653 were incurred on the abandonment
of several properties in 1999 and 1998, respectively.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $389,055 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $660,529, offset by increases in production costs paid
of $209,033, G&A expenses paid of $19,639, abandoned property costs paid of
$1,186 and working capital of $41,616. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2000 which contributed an
additional $641,727 to oil and gas receipts and an increase of $18,802 resulting
from an increase in oil production during 2000. The increase in production costs
was primarily due to increased production taxes associated with higher oil and
gas prices and additional workover and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

                                       7
   885

Net Cash Provided by Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to the
addition of oil and gas equipment on active properties.

Proceeds from disposition of assets of $57,999 for 2000 resulted from $36,906
salvage income on a fully depleted well and wells abandoned in a prior year,
$15,711 salvage income received on two wells plugged and abandoned in 2000 and
$5,382 from equipment credits on one active well. Proceeds from disposition of
assets of $21,887 for 1999 resulted from $7,583 in salvage income received on
one well plugged and abandoned during 1999, in addition to $7,544 salvage income
primarily received on fully depleted wells and $6,760 from equipment credits on
one active well.

Net Cash Used in Financing Activities

For 2000, cash distributions to the partners were $624,930, of which $6,249 was
distributed to the managing general partner and $618,681 to the limited
partners. In 1999, cash distributions to the partners were $226,214, of which
$2,262 was distributed to the managing general partner and $223,952 to the
limited partners.


                                       8
   886


ITEM 8.       FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----

                                                                                     
Financial Statements of Parker & Parsley Producing Properties 87-A, Ltd:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15





                                       9
   887



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Producing Properties 87-A, Ltd.
 (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley Producing Properties
87-A, Ltd. as of December 31, 2000 and 1999, and the related statements of
operations, partners' capital and cash flows for each of the three years in the
period ended December 31, 2000. These financial statements are the
responsibility of the Partnership's management. Our responsibility is to express
an opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Producing
Properties 87-A, Ltd. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.




                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001


                                       10
   888


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31






                                                                   2000             1999
                                                               ------------     ------------
                                                                          
              ASSETS
              ------
Current assets:
 Cash                                                          $   182,206      $  170,538
 Accounts receivable - oil and gas sales                           296,053         195,636
                                                               ------------     -----------

        Total current assets                                       478,259         366,174
                                                               ------------     -----------

Oil and gas properties - at cost, based on the
 successful efforts accounting method                            5,701,037       5,774,563
Accumulated depletion                                           (5,019,550)     (4,958,910)
                                                               ------------     -----------

        Net oil and gas properties                                 681,487         815,653
                                                               ------------     -----------

                                                               $ 1,159,746      $1,181,827
                                                               ============     ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------
Current liabilities:
 Accounts payable - affiliate                                  $    37,242      $   35,908

Partners' capital:
 Managing general partner                                           12,466          12,700
 Limited partners (24,426 interests)                             1,110,038       1,133,219
                                                               ------------     -----------

                                                                 1,122,504       1,145,919
                                                               ------------     -----------
                                                               $ 1,159,746      $1,181,827
                                                               ============     ===========


   The accompanying notes are an integral part of these financial statements.

                                       11
   889


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                 2000          1999           1998
                                              -----------   -----------   -----------
                                                                 
Revenues:
  Oil and gas                                 $ 1,514,918   $   860,305   $   807,421
  Interest                                         16,109        10,193        13,353
  Gain on disposition of assets                    37,944        25,173        24,040
                                              -----------   -----------   -----------

                                                1,568,971       895,671       844,814
                                              -----------   -----------   -----------

Costs and expenses:
  Oil and gas production                          765,021       555,988       682,634
  General and administrative                       45,448        25,809        24,223
  Impairment of oil and gas properties             59,777        43,412        37,388
  Depletion                                        69,296       109,034       383,398
  Abandoned property                               27,914        26,728        74,653
                                              -----------   -----------   -----------

                                                  967,456       760,971     1,202,296
                                              -----------   -----------   -----------

Net income (loss)                             $   601,515   $   134,700   $  (357,482)
                                              ===========   ===========   ===========

Allocation of net income (loss):
  Managing general partner                    $     6,015   $     1,347   $    (3,575)
                                              ===========   ===========   ===========

  Limited partners                            $   595,500   $   133,353   $  (353,907)
                                              ===========   ===========   ===========

Net income (loss) per limited partnership
  interest                                    $     24.38   $      5.46   $    (14.49)
                                              ===========   ===========   ===========


   The accompanying notes are an integral part of these financial statements.

                                       12
   890

                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                    Managing
                                                    general        Limited
                                                    partner        partners        Total
                                                  ----------     -----------    -----------


                                                                       
Partners' capital at January 1, 1998              $  19,487      $1,805,112     $1,824,599

  Distributions                                      (2,297)       (227,387)      (229,684)

  Net loss                                           (3,575)       (353,907)      (357,482)
                                                  ----------     -----------    -----------

Partners' capital at December 31, 1998               13,615       1,223,818      1,237,433

  Distributions                                      (2,262)       (223,952)      (226,214)

  Net income                                          1,347         133,353        134,700
                                                  ----------     -----------    -----------

Partners' capital at December 31, 1999               12,700       1,133,219      1,145,919

  Distributions                                      (6,249)       (618,681)      (624,930)

  Net income                                          6,015         595,500        601,515
                                                  ----------     -----------    -----------

Partners' capital at December 31, 2000            $  12,466      $1,110,038     $1,122,504
                                                  ==========     ===========    ===========


   The accompanying notes are an integral part of these financial statements.

                                       13
   891


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                      2000          1999           1998
                                                   ----------    ----------     ----------

                                                                       
Cash flows from operating activities:
  Net income (loss)                                $ 601,515     $ 134,700      $(357,482)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties            59,777        43,412         37,388
      Depletion                                       69,296       109,034        383,398
      Gain on disposition of assets                  (37,944)      (25,173)       (24,040)
  Changes in assets and liabilities:
      Accounts receivable                           (100,417)      (80,454)        95,326
      Accounts payable                                (8,712)       12,941        (13,546)
                                                   ----------    ----------     ----------

        Net cash provided by operating activities    583,515       194,460        121,044
                                                   ----------    ----------     ----------

Cash flows from investing activities:
  Additions to oil and gas equipment                  (4,916)       (2,818)       (11,491)
  Proceeds from disposition of assets                 57,999        21,887         83,839
                                                   ----------    ----------     ----------

        Net cash provided by investing activities     53,083        19,069         72,348
                                                   ----------    ----------     ----------

Cash flows used in financing activities:
  Cash distributions to partners                    (624,930)     (226,214)      (229,684)
                                                   ----------    ----------     ----------

Net increase (decrease) in cash                       11,668       (12,685)       (36,292)
Cash at beginning of year                            170,538       183,223        219,515
                                                   ----------    ----------     ----------

Cash at end of year                                $ 182,206     $ 170,538      $ 183,223
                                                   ==========    ==========     ==========


   The accompanying notes are an integral part of these financial statements.

                                       14
   892


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley Producing Properties 87-A, Ltd. (the "Partnership") is a
limited partnership organized in 1987 under the laws of the State of Texas. The
Partnership's managing general partner is Pioneer Natural Resources USA, Inc.
("Pioneer USA").

      The Partnership engages in oil and gas production in Texas and is not
involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income (loss) of the Partnership is included in the
individual Federal income tax returns of the

                                       15
   893

respective partners.

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of the cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.      IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $59,777, $43,412 and
$37,388 related to its proved oil and gas properties during 2000, 1999 and 1998,
respectively.

                                       16
   894

NOTE 4.      INCOME TAXES

     The financial statement basis of the Partnership's net assets and
liabilities was $1,521,385 less than the tax basis at December 31, 2000.

     The following is a reconciliation of net income (loss) per statements of
operations with the net income (loss) per Federal income tax returns for the
years ended December 31:



                                                          2000          1999           1998
                                                        --------      --------      ---------

                                                                          
   Net income (loss) per statements of operations      $ 601,515     $ 134,700     $ (357,482)
   Depletion and depreciation provisions for tax
     reporting purposes (greater than) less than
     amounts for financial reporting purposes            (12,672)       47,101        (84,454)
   Impairment of oil and gas properties for financial
     reporting purposes                                   59,777        43,412         37,388
   Other, net                                            (15,730)       (2,287)         4,922
                                                        --------      --------      ---------

         Net income (loss) per Federal income
           tax returns                                 $ 632,890     $ 222,926     $ (399,626)
                                                        ========      ========      =========


NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the net costs incurred, whether capitalized
or expensed, related to the Partnership's oil and gas producing activities for
the years ended December 31:



                                                      2000          1999           1998
                                                    --------      --------      ---------

                                                                      
      Property acquisition costs                   $   4,087     $   1,104     $   11,491
                                                    ========      ========      =========

      Development costs                            $     829     $   1,714     $      -
                                                    ========      ========      =========


      Capitalized oil and gas properties consist of the following:



                                                                 2000             1999
                                                              ----------       -----------
                                                                        
    Proved properties:
      Property acquisition costs                              $5,021,262      $  5,095,617
      Completed wells and equipment                              679,775           678,946
                                                              ----------       -----------

                                                               5,701,037         5,774,563
    Accumulated depletion                                     (5,019,550)       (4,958,910)
                                                              ----------       -----------

      Net oil and gas properties                              $  681,487      $    815,653
                                                              ==========       ===========


NOTE 6.       RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999          1998
                                                   ---------     ---------     ----------

                                                                      
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 268,224     $ 254,244     $  292,539

    Reimbursement of general and administrative
      expenses                                     $  29,711     $   1,550     $   10,723


                                       17
   895

      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees Producing Properties 87-A ("EMPL") and the Partnership are parties
to the Program agreement. EMPL is a general partnership organized for the
benefit of certain employees of Pioneer USA. EMPL was merged with Pioneer USA on
December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnership as follows:



                                                              Pioneer USA (1)   Partnership
                                                              ---------------   -----------
                                                                        
   Revenues:
     Revenues from oil and gas production, proceeds from
       sales of producing properties and all other
       revenues:
         Before payout (2)                                       4.040405%      95.959595%
         After payout                                           19.191920%      80.808080%
   Costs and expenses:
     Property acquisition costs, operating costs, general
       and administrative expenses and other costs:
         Before payout (2)                                       4.040405%      95.959595%
         After payout                                           19.191920%      80.808080%


  (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level and 86 limited partner interests owned by
        Pioneer USA.

  (2)   The Partnership has not reached payout.

NOTE 7.       OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.


                                       18
   896




                                                              Oil and NGLs          Gas
                                                                 (bbls)            (mcf)
                                                              ------------       ----------

                                                                          
  Net proved reserves at January 1, 1998                          719,789          996,755
  Revisions                                                      (302,841)        (385,883)
  Production                                                      (64,367)         (56,240)
                                                                ----------       ----------

  Net proved reserves at December 31, 1998                        352,581          554,632
  Revisions                                                       461,643          633,460
  Production                                                      (53,101)         (53,145)
                                                                ----------       ----------

  Net proved reserves at December 31, 1999                        761,123        1,134,947
  Revisions                                                         6,756         (376,058)
  Production                                                      (53,656)         (45,872)
                                                                ----------       ----------

  Net proved reserves at December 31, 2000                        714,223          713,017
                                                                ==========       ==========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.58 per barrel of NGLs and $7.60 per mcf of gas,
discounted at 10% was approximately $4,683,000 and undiscounted was $9,322,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.

                                       19
   897



                                                                   For the years ended December 31,
                                                                --------------------------------------
                                                                   2000          1999         1998
                                                                -----------   -----------  -----------
                                                                             (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                           $   22,258    $   18,298   $    3,739
  Future production costs                                          (12,936)      (10,698)      (2,777)
                                                                -----------   -----------  -----------

                                                                     9,322         7,600          962
  10% annual discount factor                                        (4,639)       (3,477)        (323)
                                                                -----------   -----------  -----------

  Standardized measure of discounted future net cash flows      $    4,683    $    4,123   $      639
                                                                ===========   ===========  ===========




                                                                   For the years ended December 31,
                                                                --------------------------------------
                                                                   2000          1999         1998
                                                                -----------   -----------  -----------
                                                                             (in thousands)
                                                                                  
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs                  $     (750)  $      (304)  $     (125)
    Net changes in prices and production costs                       1,685         1,668       (1,687)
    Revisions of previous quantity estimates                          (339)        3,013         (453)
    Accretion of discount                                              412            64          275
    Changes in production rates, timing and other                     (448)         (957)        (118)
                                                                  --------     ---------     --------

    Change in present value of future net revenues                     560         3,484       (2,108)
                                                                  --------     ---------     --------

    Balance, beginning of year                                       4,123           639        2,747
                                                                  --------     ---------     --------

    Balance, end of year                                        $    4,683   $     4,123   $      639
                                                                 =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
           Plains Marketing, L.P.                     59%            60%            -
           Phillips Petroleum Company                 15%            14%           16%
           TEPPCO Crude Oil LLC                       11%             -             -
           Genesis Crude Oil, L.P.                     -              -            66%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
Phillips Petroleum Company and TEPPCO Crude Oil LLC were $78,270, $54,144 and
$29,228, respectively, which are included in the caption "Accounts receivable -
oil and gas sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.       PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Partnership

                                       20
   898

      affairs. As managing general partner and operator of the Partnership's
      properties, all production expenses are incurred by Pioneer USA and billed
      to the Partnership. The majority of the Partnership's oil and gas revenues
      are received directly by Pioneer USA prior to being paid to the
      Partnership. Under the limited partnership agreement, the managing general
      partner pays 1% of the Partnership's acquisition, drilling and completion
      costs and 1% of its operating and general and administrative expenses. In
      return, it is allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of
      $12,213,000. Pioneer USA is required to contribute amounts equal to 1% of
      initial Partnership capital less commission and organization and offering
      costs allocated to the limited partners and to contribute amounts
      necessary to pay costs and expenses allocated to it under the Partnership
      agreement to the extent its share of revenues does not cover such costs.

ITEM 9.       CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
               AND FINANCIAL DISCLOSURE

None.




                                       21
   899


                                    PART III

ITEM 10.      DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                      Age at
                                    December 31,
       Name                            2000                       Position
       ----                            ----                       --------

                                                
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

                                       22
   900


      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.

                                       23
   901


ITEM 11.       EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the limited
partnership agreement, Pioneer USA pays 1% of the Program's acquisition,
drilling and completion costs and 1% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 1% of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.       SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 86 limited partnership interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer of director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:

                                       24
   902




                                                        2000          1999           1998
                                                   ------------- -------------  -------------

                                                                       
  Payment of lease operating and supervision
    charges in accordance with standard
    industry operating agreements                  $268,224      $ 254,244      $292,539

  Reimbursement of general and administrative
    expenses                                       $ 29,711      $   1,550      $ 10,723


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.


                                       25
   903


                                     PART IV


ITEM 14.      EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                 Statements of partners' capital for the years ended December
                   31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                 Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.

                                       26
   904


                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                              PARKER & PARSLEY PRODUCING
                              PROPERTIES 87-A, LTD.

Dated: March 26, 2001         By:   Pioneer Natural Resources USA, Inc.
                                     Managing General Partner


                              By:   /s/ Scott D. Sheffield
                                    ------------------------------------
                                    Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                      
/s/ Scott D. Sheffield               President of Pioneer USA                 March 26, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                  Executive Vice President, Chief          March 26, 2001
-------------------------------      Financial Officer and Director of
Timothy L. Dove                      Pioneer USA


/s/ Dennis E. Fagerstone             Executive Vice President and             March 26, 2001
-------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                  Executive Vice President, General        March 26, 2001
-------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                     Executive Vice President - Domestic      March 26, 2001
-------------------------------      Operations and Director of Pioneer
Danny Kellum                         USA


/s/ Rich Dealy                       Vice President and Chief Accounting      March 26, 2001
-------------------------------      Officer of Pioneer USA
Rich Dealy


                                       27
   905


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----

                                                                          
       3(a)               Amended and Restated Certificate of Limited               -
                          Partnership of Parker & Parsley Producing
                          Properties 87-A, Ltd. incorporated by reference
                          to Exhibit 3a of Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-11193)

       4(a)               Agreement of Limited Partnership of Parker                -
                          & Parsley Producing Properties 87-A, Ltd.
                          incorporated by reference to Exhibit A of
                          Amendment No, 1 of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-11193)

       4(b)               Subscription Agreement incorporated by                    -
                          reference to Exhibit C of Amendment No. 1
                          of the Partnership's Registration Statement
                          on Form S-1 (Registration No. 33-11193)

       4(b)               Power of Attorney incorporated by reference               -
                          to Exhibit B of Amendment No. 1 of the
                          Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-11193)

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit
                          4c of the Partnership's Registration Statement
                          on Form S-1 (Registration No. 33-11193)

      10(b)               Program Agreement incorporated by reference               -
                          to Exhibit B of Amendment No. 1 of the
                          Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-11193)




                                       28
   906


                PARKER & PARSLEY PRODUCING PROPERTIES 87-A, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  366,869   $1,514,918   $  860,305   $  807,421   $1,244,727   $1,772,612
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
      settlement, net              $     --   $       --   $       --   $       --   $       --   $       --   $   19,935
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
      gas properties               $          $       --   $   59,777   $   43,412   $   37,388   $  420,264   $   39,087
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  184,335   $  601,515   $  134,700   $ (357,482)  $ (397,297)  $  984,877
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
         partner                   $          $    1,843   $    6,015   $    1,347   $   (3,575)  $   (3,973)  $    9,849
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  182,492   $  595,500   $  133,353   $ (353,907)  $ (393,324)  $  975,028
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
      (loss) per limited
      partnership interest         $          $     7.47   $    24.38   $     5.46   $   (14.49)  $   (16.10)  $    39.92
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
      distributions per limited
      partnership interest         $          $     5.46   $    25.33   $     9.17   $     9.31   $    24.14   $    36.01(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,232,462   $1,159,746   $1,181,827   $1,270,446   $1,871,158   $2,817,583
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement of $.81 per limited partnership interest in
     1996.



   907
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

  PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED         , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS         , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Producing Properties 87-B, Ltd. and supplements the proxy statement/prospectus
dated        , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Producing Properties 87-B, Ltd.:

     o   A table containing:

         --       the aggregate initial investment by the limited partners


         --       the aggregate historical limited partner distributions through
                  July 31, 2001

         --       the merger value attributable to partnership interests of
                  limited partners, excluding Pioneer USA

         --       the merger value per $1,000 limited partner investment

         --       the merger value per $1,000 limited partner investment as a
                  multiple of distributions for the past four quarterly
                  distributions including the distribution in July 2001


         --       the book value per $1,000 limited partner investment as of
                  March 31, 2001 and as of December 31, 2000


         --       the going concern value per $1,000 limited partner investment

         --       the liquidation value per $1,000 limited partner investment


         --       the ordinary tax loss per $1,000 limited partner investment in
                  year of initial investment

     o   Information about:


         --       the legal opinion for the limited partners

         --       the term of the partnership


     o   The partnership's quarterly report on Form 10-Q, including management's
         discussion and analysis of financial condition and results of
         operations, for the three months ended March 31, 2001

     o   The partnership's annual report on Form 10-K, including management's
         discussion and analysis of financial condition and results of
         operations, for the year ended December 31, 2000

     o   Selected historical financial data for the partnership for the three
         months ended March 31, 2001 and 2000 and the five years ended December
         31, 2000


                                      -1-
   908
                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.

                         SUPPLEMENTAL INFORMATION TABLE




                                                                                                       
Aggregate Initial Investment by the Limited Partners(a)                                                   $ 6,096

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                               $ 6,870

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a),(b)      $ 2,336

Merger Value per $1,000 Limited Partner Investment(b),(c)                                                 $389.51

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the                    3.84 times
past four quarterly distributions including the distribution in July 2001(b),(c)

Book Value per $1,000 Limited Partner Investment:

     --  as of March 31, 2001(c)                                                                          $130.81

     --  as of December 31, 2000(c)                                                                       $136.41

Going Concern Value per $1,000 Limited Partner Investment(c),(d)                                          $363.70

Liquidation Value per $1,000 Limited Partner Investment(c),(e)                                            $377.84

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(f)                      --



----------

(a) Stated in thousands.


(b) The merger value for the partnership is equal to the sum of the present
    value of estimated future net revenues from the partnership's estimated oil
    and gas reserves and its net working capital, in each case as of March 31,
    2001, less its pro rata share, based on its reserve value, of the estimated
    expenses and fees of the mergers of all of the partnerships and less the
    cash distribution on or about July 9, 2001, by the partnership to its
    partners.

(c) Interests in some partnerships were sold in units at prices other than
    $1,000. We have presented this information based on a $1,000 initial
    investment for ease of use and comparison among partnerships. You should not
    assume that the amount shown per $1,000 investment is the same as the value
    or amount attributable to a single unit investment.

(d) The going concern value for the partnership is based upon: (1) the sum of
    (A) the estimated net cash flow from the sale of the partnership's reserves
    during a 10-year operating period and (B) the estimated residual value from
    the sale of the partnership's remaining reserves at the end of the operating
    period, in each case using the same pricing and discount rate as in the
    merger value calculation, less (2) partnership level general and
    administrative expenses.

(e) The liquidation value for the partnership is based upon the sale of the
    partnership's reserves at the reserve value, less liquidation expenses which
    are estimated to be the sum of (1) the partnership's pro rata share of the
    merger expenses and fees described in footnote (b) above and (2) 3% of the
    partnership's reserve value. The liquidation expenses represent estimated
    costs to retain an investment banker or broker to sell the assets of the
    partnership and the legal and other closing costs associated with such
    transaction, including the wind-down costs of the partnership.

(f) Not applicable. Since this partnership purchased producing properties, there
    were no intangible drilling and development costs nor any related write-off
    for tax purposes.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

    The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
(1) neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners; and (2)
neither the grant nor exercise of such right will result in the loss of any
limited partner's limited liability. In addition, the counsel designated to
render the opinion must be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

    The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-

   909

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-11193-2


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
             (Exact name of Registrant as specified in its charter)


                       Texas                                75-2205943
          ---------------------------------            ---------------------
           (State or other jurisdiction of                (I.R.S. Employer
           incorporation or organization)              Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
           (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]





   910



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.

                                TABLE OF CONTENTS




                                                                      Page

                          Part I. Financial Information

                                                                     
Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000.....................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000..........................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001...................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000..........................    6

           Notes to Financial Statements............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K.........................   10

           Signatures...............................................   11



                                        2

   911



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                          Part I. Financial Information

Item 1.     Financial Statements

                                 BALANCE SHEETS



                                                     March 31,     December 31,
                                                       2001            2000
                                                    -----------    ------------
                                                    (Unaudited)

                       ASSETS
                                                             
Current assets:
  Cash                                               $    3,688     $   19,277
  Accounts receivable - oil and gas sales               179,564        194,002
                                                     ----------     ----------
          Total current assets                          183,252        213,279
                                                     ----------     ----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                4,831,858      4,829,203
Accumulated depletion                                (4,191,489)    (4,181,937)
                                                     ----------     ----------
          Net oil and gas properties                    640,369        647,266
                                                     ----------     ----------
                                                     $  823,621     $  860,545
                                                     ==========     ==========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $   17,965     $   20,375

Partners' capital:
  Managing general partner                                8,316          8,661
  Limited partners (12,191 interests)                   797,340        831,509
                                                     ----------     ----------
                                                        805,656        840,170
                                                     ----------     ----------
                                                     $  823,621     $  860,545
                                                     ==========     ==========




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   912



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                     Three months ended
                                                          March 31,
                                                 -------------------------
                                                    2001           2000
                                                 ----------     ----------
                                                          
Revenues:
  Oil and gas                                     $ 238,043      $ 263,792
  Interest                                            1,180          1,071
  Gain on disposition of assets                          --          8,294
                                                  ---------      ---------
                                                    239,223        273,157
                                                  ---------      ---------
Costs and expenses:
  Oil and gas production                             87,509        109,436
  General and administrative                          7,141          7,914
  Depletion                                           9,552         10,726
                                                  ---------      ---------
                                                    104,202        128,076
                                                  ---------      ---------
Net income                                        $ 135,021      $ 145,081
                                                  =========      =========
Allocation of net income:
  Managing general partner                        $   1,350      $   1,451
                                                  =========      =========
  Limited partners                                $ 133,671      $ 143,630
                                                  =========      =========
Net income per limited partnership interest       $   10.96      $   11.78
                                                  =========      =========





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   913



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                         Managing
                                         general       Limited
                                         partner       partners        Total
                                        ---------     ----------     ----------


                                                             
Balance at January 1, 2001               $  8,661      $ 831,509      $ 840,170

    Distributions                          (1,695)      (167,840)      (169,535)

    Net income                              1,350        133,671        135,021
                                         --------      ---------      ---------

Balance at March 31, 2001                $  8,316      $ 797,340      $ 805,656
                                         ========      =========      =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   914



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                          Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
   Net income                                           $ 135,021     $ 145,081
    Adjustments to reconcile net income to net cash
     provided by operating activities:
       Depletion                                            9,552        10,726
       Gain on disposition of assets                          -          (8,294)
   Changes in assets and liabilities:
     Accounts receivable                                   14,438       (66,171)
     Accounts payable                                      (2,410)        6,672
                                                        ---------     ---------
          Net cash provided by operating activities       156,601        88,014
                                                        ---------     ---------
Cash flows from investing activities:
   Additions to oil and gas properties                     (2,655)           --
   Proceeds from disposition of assets                         --        13,944
                                                        ---------     ---------
          Net cash provided by (used in) investing
            activities                                     (2,655)       13,944
                                                        ---------     ---------
Cash flows used in financing activities:
   Cash distributions to partners                        (169,535)     (114,082)
                                                        ---------     ---------
Net decrease in cash                                      (15,589)      (12,124)
Cash at beginning of period                                19,277        21,724
                                                        ---------     ---------
Cash at end of period                                   $   3,688     $   9,600
                                                        =========     =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   915



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley Producing Properties 87-B, Ltd. (the "Partnership") is a
limited partnership organized in 1987 under the laws of the State of Texas.

The Partnership engages in oil and gas production in Texas and is not involved
in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues decreased 10% to $238,043 for the three
months ended March 31, 2001 as compared to $263,792 for the same period in 2000.
The decrease in revenues resulted from a decline in production, offset by higher
average prices received. For the three months ended March 31, 2001, 5,392
barrels of oil, 1,750 barrels of natural gas liquids ("NGLs") and 9,834 mcf of
gas were sold, or 8,781 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 7,007 barrels of oil, 3,011 barrels of NGLs and 14,555 mcf
of gas were sold, or 12,444 BOEs. Of the decrease, 1,646 BOE's are attributable

                                        7

   916



to the fact that on April 1, 2000 the Partnership's revenue and operating
expense allocation reverted to 80.808081% from 95.959595% pursuant to the
Program Agreement governing the Partnership which provides for a reversionary
interest of 80.080801% once cumulative distributions equal initial partner's
capital ("Reversionary Interest").

The average price received per barrel of oil decreased $.40, or 1%, from $27.54
for the three months ended March 31, 2000 to $27.14 for the same period in 2001.
The average price received per barrel of NGLs increased $4.14, or 28%, from
$14.93 for the three months ended March 31, 2000 to $19.07 for the same period
in 2001. The average price received per mcf of gas increased 233% from $1.78
during the three months ended March 31, 2000 to $5.93 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $8,294 was recognized during the three months
ended March 31, 2000. The gain recognized was due to equipment credits received
on fully depleted wells.

Costs and Expenses:

Total costs and expenses decreased to $104,202 for the three months ended March
31, 2001 as compared to $128,076 for the same period in 2000, a decrease of
$23,874, or 19%. This decrease was due to declines in production costs,
depletion and general and administrative expenses ("G&A").

Production costs were $87,509 for the three months ended March 31, 2001 and
$109,436 for the same period in 2000 resulting in a $21,927 decrease, or 20%.
Lease operating costs and production taxes declined 15% which were attributable
to the Revisionary Interest change and production costs declined 5% resulting
from lower well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
decreased 10% from $7,914 for the three months ended March 31, 2000 to $7,141
for the same period in 2001, primarily due to the Revisionary Interest change as
noted above.

Depletion was $9,552 for the three months ended March 31, 2001 as compared to
$10,726 for the same period in 2000, a decrease of $1,174, or 11%. This decrease
was primarily due to a decline in oil production of 1,615 barrels for the period
ended March 31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $68,587 during the three
months ended March 31, 2001 from the same period in 2000. The increase was due
to reductions in production costs of $21,927, G&A expenses of $773 and working
capital of $71,527, offset by a decrease in oil and gas sales receipts of
$25,640. The decline in production costs was primarily due to the Reversionary

                                        8

   917



Interest change and lower well maintenance. The decrease in oil and gas sales
receipts resulted in $95,880 from the decline in production in 2001, offset by
the increase in commodity prices during 2001 which contributed an additional
$70,240 to oil and gas receipts.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 were related to expenditures for upgrades of oil and gas
equipment on active properties.

Proceeds from disposition of assets of $13,944 were recognized during the three
months ended March 31, 2000. The proceeds recognized were primarily from
equipment credits on fully depleted wells.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $169,535, of which $1,695 was distributed to the managing general partner
and $167,840 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $114,082, of which $1,141 was
distributed to the managing general partner and $112,941 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.

                                        9

   918



                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.



                                       10

   919


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                         PARKER & PARSLEY PRODUCING
                                          PROPERTIES 87-B, LTD.


                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 14, 2001               By:      /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       11



   920
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-11193-2


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
             (Exact name of Registrant as specified in its charter)

            TEXAS                                               75-2205943
-------------------------------                           ----------------------
(State or other jurisdiction of                             (I.R.S. Employer
incorporation or organization)                            Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS        75039
----------------------------------------------------------------      ----------
         (Address of principal executive offices)                     (Zip code)

       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                  LIMITED PARTNERSHIP INTERESTS ($500 PER UNIT)
                  ---------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$5,997,500.

       As of March 8, 2001, the number of outstanding limited partnership
                             interests was 12,191.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   921

                                     PART I

ITEM 1.       BUSINESS

Parker & Parsley Producing Properties 87-B, Ltd. (the "Partnership") is a
limited partnership organized in 1987 under the laws of the state of Texas. The
Partnership's managing general partner is Pioneer Natural Resources USA, Inc.
("Pioneer USA"). Pioneer USA is a wholly-owned subsidiary of Pioneer Natural
Resources Company ("Pioneer"). As of March 8, 2001, the Partnership had 12,191
limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 32%, 22% and 20% were attributable to
sales made to Plains Marketing, L.P., TEPPCO Crude Oil LLC and Phillips
Petroleum Company, respectively. Pioneer USA is of the opinion that the loss of
any one purchaser would not have an adverse effect on its ability to sell its
oil, natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial liability due to pollution and other
environmental damages. Although the Partnership believes that

                                       2
   922

its business operations do not impair environmental quality and that its costs
of complying with any applicable environmental regulations are not currently
significant, the Partnership cannot predict what, if any, effect these
environmental regulations may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.      PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

The Partnership completed seven purchases of producing properties. These
acquisitions involved the purchase of working interests in 54 properties. The
Partnership also participated in the drilling of two oil and gas wells during
1988 which were completed as producers. Additionally, the Partnership purchased
15 overriding royalty interests effective January 1, 1990 and two additional
overriding royalty interests during 1991. Twenty-two uneconomical wells have
been abandoned. At December 31, 2000, the Partnership had 34 producing oil and
gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.      LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.         SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.

                                       3
   923


                                     PART II

ITEM 5.         MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                 DISTRIBUTIONS

At March 8, 2001, the Partnership had 12,191 outstanding limited partnership
interests held of record by 550 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $586,016 and $170,405, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                   2000         1999          1998         1997         1996
                                ---------     ---------     --------     ---------    ---------

                                                                      
Operating results:
-----------------
  Oil and gas sales            $  982,604    $ 625,861    $  532,606   $  846,163    $  980,232
                                =========     ========     =========    =========     =========

  Impairment of oil and gas
   properties                  $      -      $     -      $   35,017   $  317,255    $   42,277
                                =========     ========     =========    =========     =========

  Net income (loss)            $  562,621    $ 163,148    $ (118,738)  $ (142,439)   $  303,380
                                =========     ========     =========    =========     =========

  Allocation of net income
    (loss):
   Managing general partner    $    5,626    $   1,631    $   (1,187)  $   (1,424)   $    3,034
                                =========     ========     =========    =========     =========

   Limited partners            $  556,995    $ 161,517    $ (117,551)  $ (141,015)   $  300,346
                                =========     ========     =========    =========     =========

  Limited partners' net income
   (loss) per limited
   partnership interest        $    45.69    $   13.25    $    (9.64)  $   (11.57)   $    24.64
                                =========     ========     =========    =========     =========

  Limited partners' cash
   distributions per limited
   partnership interest        $    48.07    $   13.98    $    16.41   $    39.20    $    35.59
                                =========     ========     =========    =========     =========

At year end:
-----------
  Identifiable assets          $  860,545    $ 892,550    $  878,401   $1,241,161    $1,823,614
                                =========     ========     =========    =========     =========


                                       4
   924


ITEM 7.       MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
               RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 57% to $982,604 for 2000 as
compared to $625,861 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 22,713
barrels of oil, 10,402 barrels of natural gas liquids ("NGLs") and 49,380 mcf of
gas were sold, or 41,345 barrel of oil equivalents ("BOEs"). In 1999, 24,976
barrels of oil, 10,794 barrels of NGLs and 48,774 mcf of gas were sold, or
43,899 BOEs. Of the decrease, 5,393 BOEs are attributable to the fact that on
April 1, 2000, the Partnership's revenue and operating expense allocation
reverted to 80.808081% from 95.959595% pursuant to the Program Agreement
governing the Partnership which provides for a reversionary interest of
80.808081% once cumulative distributions equal initial partner's capital
("Reversionary Interest"). This is offset by a production increase of 2,839
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $11.92, or 68%, from
$17.44 in 1999 to $29.36 in 2000. The average price received per barrel of NGLs
increased $6.36, or 62%, from $10.32 in 1999 to $16.68 in 2000. The average
price received per mcf of gas increased 78% from $1.62 in 1999 to $2.88 in 2000.
The market price for oil and gas has been extremely volatile in the past decade
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gains on disposition of assets of $8,294 and $11,482 were recognized in 2000 and
1999, respectively. The gain from 2000 was from equipment salvage on one well
abandoned in a prior year. The gain from 1999 was from equipment salvage of
$12,955 on one well plugged and abandoned in a prior year, offset by a $1,473
loss on the write-off of basis on one well plugged and abandoned during 1999.

Total costs and expenses decreased in 2000 to $434,793 as compared to $477,552
in 1999, a decrease of $42,759, or 9%. The decrease was primarily attributable
to declines in depletion, production costs and abandoned property costs, offset
by an increase in general and administrative expenses ("G&A").

Production costs were $347,938 in 2000 and $364,187 in 1999, resulting in a
decrease of $16,249, or 4%. Lease operating costs and production taxes declined
12% which was attributable to the Reversionary Interest change, offset by an 8%
increase in production costs resulting from high production taxes due to higher
oil and gas prices and additional well maintenance costs incurred to stimulate
well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
79%, from $18,776 in 1999 to

                                       5
   925

$33,521 in 2000 primarily due to a higher percentage of the managing general
partner's G&A being allocated (limited to 3% of oil and gas revenues) as a
result of increased oil and gas revenues. The Partnership paid the managing
general partner $27,424 in 2000 and $8,400 in 1999 for G&A incurred on behalf of
the Partnership. The remaining G&A was paid directly by the Partnership. The
managing general partner determines the allocated expenses based upon the level
of activity of the Partnership relative to the non-partnership activities of the
managing general partner. The method of allocation has been consistent over the
past several years with certain modifications incorporated to reflect changes in
Pioneer USA's overall business activities.

Depletion was $53,334 in 2000 as compared to $79,975 in 1999, a decrease of
$26,641, or 33%. This decrease was primarily due to a 51,092 barrels of oil
increase in proved reserves during 2000 as a result of higher commodity prices.

Abandoned property costs of $14,614 incurred in 1999 were related to the
temporary abandonment of one well during 1999 and two wells plugged and
abandoned in prior years.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 18% to $625,861 from
$532,606 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 24,976 barrels of oil,
10,794 barrels of NGLs and 48,774 mcf of gas were sold, or 43,899 BOEs. In 1998,
29,481 barrels of oil, 11,315 barrels of NGLs and 50,220 mcf of gas were sold,
or 49,166 BOEs.

The average price received per barrel of oil increased $4.39, or 34%, from
$13.05 in 1998 to $17.44 in 1999. The average price received per barrel of NGLs
increased $3.74, or 57%, from $6.58 in 1998 to $10.32 in 1999. The average price
received per mcf of gas increased 11% from $1.46 in 1998 to $1.62 in 1999.

Gain on disposition of assets of $11,482 was recognized in 1999 from equipment
salvage of $12,955 on one well plugged and abandoned in a prior year, offset by
a $1,473 loss on the write-off of basis on one well plugged and abandoned during
1999. In 1998, $4,248 gain on disposition of assets was recognized from proceeds
received from equipment salvage on wells plugged in prior years.

Total costs and expenses decreased in 1999 to $477,552 as compared to $659,670
in 1998, a decrease of $182,118, or 28%. The decrease was primarily attributable
to declines in depletion, the impairment of oil and gas properties, production
costs and abandoned property costs, offset by an increase in G&A.

Production costs were $364,187 in 1999 and $385,648 in 1998, resulting in a
$21,461 decrease, or 6%. The decrease was the result of declines in well
maintenance costs, ad valorem taxes and workover expenses.

During this period, G&A increased 18% from $15,978 in 1998 to $18,776 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $8,400 in
1999 and $9,662 in 1998 for G&A incurred on behalf of the Partnership.

                                       6
   926

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $35,017 related to its oil and gas properties during 1998.

Depletion was $79,975 in 1999 compared to $206,289 in 1998, a decrease of
$126,314, or 61%. This decrease was primarily due to an increase in proved
reserves of 180,622 barrels of oil during 1999 as a result of higher commodity
prices, a reduction in the Partnership's net depletable basis from charges taken
in accordance with SFAS 121 during the fourth quarter of 1998 and a decline in
oil production of 4,505 barrels for the period ended December 31, 1999 compared
to the same period in 1998.

Abandoned property costs of $14,614 incurred in 1999 were related to the
temporary abandonment of one well during 1999 and two wells plugged and
abandoned in prior years. Expenses of $16,738 were incurred in 1998 to plug and
abandon one oil and gas well which was temporarily abandoned in a prior year.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

                                       7
   927


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $392,559 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $359,902 and declines in production costs paid of
$16,249, abandoned property costs paid of $14,614 and working capital of
$16,539, offset by an increase in G&A expenses paid of $14,745. The increase in
oil and gas receipts resulted from the increase in commodity prices during 2000
which contributed an additional $431,139 to oil and gas receipts, offset by
$71,237 resulting from the decline in production during 2000. The decrease in
production costs was primarily due to the Reversionary Interest change, offset
by higher production taxes associated with high oil and gas prices and
additional well maintenance costs incurred to stimulate well production. The
increase in G&A was primarily due to higher percentage of the managing general
partner's G&A being allocated (limited to 3% of oil and gas revenues) as a
result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during 1999 were primarily for
expenditures related to upgrades of equipment on various oil and gas properties.

Proceeds of $13,943 and $12,956 were recognized during 2000 and 1999,
respectively, from equipment salvage on wells abandoned in prior years.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $591,935, of which $5,919 was
distributed to the managing general partner and $586,016 to the limited
partners. In 1999, cash distributions to the partners were $172,065, of which
$1,660 was distributed to the managing general partner and $170,405 to the
limited partners.

                                       8
   928


ITEM 8.      FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA


                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----

                                                                                     
Financial Statements of Parker & Parsley Producing Properties 87-B, Ltd.:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15



                                       9
   929



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Producing Properties 87-B, Ltd.
 (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley Producing Properties
87-B, Ltd. as of December 31, 2000 and 1999, and the related statements of
operations, partners' capital and cash flows for each of the three years in the
period ended December 31, 2000. These financial statements are the
responsibility of the Partnership's management. Our responsibility is to express
an opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Producing
Properties 87-B, Ltd. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.




                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001

                                       10
   930


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                         (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                  December 31






                                                                   2000             1999
                                                               ------------     ------------
                                                                          
              ASSETS
              ------
Current assets:
  Cash                                                           $   19,277     $   21,724
  Accounts receivable - oil and gas sales                           194,002        164,577
                                                                 ----------     ----------

      Total current assets                                          213,279        186,301
                                                                 ----------     ----------

Oil and gas properties - at cost, based on
  the successful efforts accounting method                        4,829,203      4,837,591
Accumulated depletion                                            (4,181,937)    (4,131,342)
                                                                 ----------     ----------

      Net oil and gas properties                                    647,266        706,249
                                                                 ----------     ----------

                                                                 $  860,545     $  892,550
                                                                 ==========     ==========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------
Current liabilities:
  Accounts payable - affiliate                                   $   20,375     $   23,066

Partners' capital:
  Managing general partner                                            8,661          8,954
  Limited partners (12,191 interests)                               831,509        860,530
                                                                 ----------     ----------

                                                                    840,170        869,484

                                                                 $  860,545     $  892,550
                                                                 ==========     ==========


   The accompanying notes are an integral part of these financial statements.

                                       11
   931

                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                      2000          1999           1998
                                                   ---------     ---------      ---------

                                                                       
Revenues:
 Oil and gas                                       $ 982,604     $ 625,861      $ 532,606
 Interest                                              6,516         3,357          4,078
 Gain on disposition of assets                         8,294        11,482          4,248
                                                   ---------     ---------      ---------

                                                     997,414       640,700        540,932
                                                   ---------     ---------      ---------

Costs and expenses:
 Oil and gas production                              347,938       364,187        385,648
 General and administrative                           33,521        18,776         15,978
 Impairment of oil and gas properties                    -             -           35,017
 Depletion                                            53,334        79,975        206,289
 Abandoned property                                      -          14,614         16,738
                                                   ---------     ---------      ---------

                                                     434,793       477,552        659,670
                                                   ---------     ---------      ---------

Net income (loss)                                  $ 562,621     $ 163,148      $(118,738)
                                                   =========     =========      =========

Allocation of net income (loss):
 Managing general partner                          $   5,626     $   1,631      $  (1,187)
                                                   =========     =========      =========

 Limited partners                                  $ 556,995     $ 161,517      $(117,551)
                                                   =========     =========      =========

Net income (loss) per limited partnership
 interest                                          $   45.69     $   13.25      $   (9.64)
                                                   =========     =========      =========


   The accompanying notes are an integral part of these financial statements.

                                       12
   932


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL





                                                    Managing
                                                    general        Limited
                                                    partner        partners        Total
                                                  ----------     -----------    -----------
                                                                       
Partners' capital at January 1, 1998              $   11,934     $1,186,985     $1,198,919

   Distributions                                      (1,764)      (200,016)      (201,780)

   Net loss                                           (1,187)      (117,551)      (118,738)
                                                  ----------     ----------     ----------

Partners' capital at December 31, 1998                 8,983        869,418        878,401

   Distributions                                      (1,660)      (170,405)      (172,065)

   Net income                                          1,631        161,517        163,148
                                                  ----------     ----------     ----------

Partners' capital at December 31, 1999                 8,954        860,530        869,484

   Distributions                                      (5,919)      (586,016)      (591,935)

   Net income                                          5,626        556,995        562,621
                                                  ----------     ----------     ----------

Partners' capital at December 31, 2000            $    8,661     $  831,509     $  840,170
                                                  ==========     ==========     ==========



   The accompanying notes are an integral part of these financial statements.

                                       13
   933


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                      2000          1999           1998
                                                   ----------    ----------     ----------
                                                                       
Cash flows from operating activities:
 Net income (loss)                                 $ 562,621     $ 163,148     $ (118,738)
 Adjustments to reconcile net income (loss) to
   net cash provided by operating activities:
     Gain on disposition of assets                    (8,294)      (11,482)        (4,248)
     Impairment of oil and gas properties                -             -           35,017
     Depletion                                        53,334        79,975        206,289
 Changes in assets and liabilities
     Accounts receivable                             (29,425)      (75,008)        65,047
     Accounts payable                                 (2,691)       26,353        (42,242)
                                                   ---------     ---------     ----------

       Net cash provided by operating activities     575,545       182,986        141,125
                                                   ---------     ---------     ----------

Cash flows from investing activities:
 Additions to oil and gas equipment                      -         (12,012)        (8,617)
 Proceeds from disposition of assets                  13,943        12,956          4,248
                                                   ---------     ---------     ----------

       Net cash provided by (used in)
          investing activities                        13,943           944         (4,369)
                                                   ---------     ---------     ----------

Cash flows used in financing activities:
 Cash distributions to partners                     (591,935)     (172,065)      (201,780)
                                                   ---------     ---------     ----------

Net increase (decrease) in cash                       (2,447)       11,865        (65,024)
Cash at beginning of year                             21,724         9,859         74,883
                                                   ---------       -------     ----------

Cash at end of year                                $  19,277     $  21,724     $    9,859
                                                   =========     =========     ==========


   The accompanying notes are an integral part of these financial statements.

                                       14
   934


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley Producing Properties 87-B, Ltd. (the "Partnership") is a
limited partnership organized in 1987 under the laws of the State of Texas. The
Partnership's managing general partner is Pioneer Natural Resources USA, Inc.
("Pioneer USA").

      The Partnership engages in oil and gas production in Texas and is not
involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.


      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

                                       15
   935

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.      IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $35,017 related to its
proved oil and gas properties during 1998.

                                       16
   936

NOTE 4.      INCOME TAXES

     The financial statement basis of the Partnership's net assets and
liabilities was $838,681 less than the tax basis at December 31, 2000.

     The following is a reconciliation of net income (loss) per statements of
operations with the net income (loss) per Federal income tax returns for the
years ended December 31:



                                                          2000          1999           1998
                                                        --------      --------      ---------

                                                                          
  Net income (loss) per statements of operations       $ 562,621     $ 163,148      $(118,738)
  Depletion and depreciation provisions for tax
    reporting purposes (greater than) less than
    amounts for financial reporting purposes             (39,072)        7,412        (59,976)
  Impairment of oil and gas properties for financial
    reporting purposes                                       -             -           35,017
  Abandoned property dispositions for tax reporting
    greater than (less than) amounts for financial
    reporting purposes                                       -             -         (218,079)
  Other, net                                               4,370        (7,638)         3,376
                                                         -------       -------        -------

      Net income (loss) per Federal income tax
        returns                                        $ 527,919     $ 162,922      $(358,400)
                                                        ========      ========       ========


NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                          2000          1999           1998
                                                        --------      --------      ---------

                                                                          
   Property acquisition costs                          $     -       $  (2,313)     $   6,754
                                                        ========      ========       ========

   Development costs                                   $     -       $   4,136      $   1,863
                                                        ========      ========       ========


      Capitalized oil and gas properties consist of the following:



                                                                 2000             1999
                                                              ----------       ----------
                                                                        
  Proved properties:
    Property acquisition costs                               $ 3,288,184      $  3,289,170
    Completed wells and equipment                              1,541,019         1,548,421
                                                               ---------        ----------

                                                               4,829,203         4,837,591
  Accumulated depletion                                       (4,181,937)       (4,131,342)
                                                               ----------       ----------

        Net oil and gas properties                           $   647,266      $    706,249
                                                               =========        ==========


                                       17
   937


NOTE 6.       RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                          2000          1999           1998
                                                        --------      --------      ---------

                                                                          
  Payment of lease operating and supervision
    charges in accordance with standard
    industry operating agreements                      $ 121,257     $  137,769     $ 144,149

  Reimbursement of general and administrative
    expenses                                           $  27,424     $    8,400     $   9,662


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Producing Properties 87-B Employees ("EMPL") and the Partnership are parties
to the Program agreement. EMPL is a general partnership organized for the
benefit of certain employees of Pioneer USA. EMPL was merged with Pioneer USA on
December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnership as follows:



                                                             Pioneer USA (1)    Partnership
                                                             ---------------    -----------
                                                                        
   Revenues:
     Revenues from oil and gas production, proceeds from
       sales of producing properties and all other
       revenues:
         Before payout                                           4.040405%      95.959595%
         After payout (2)                                       19.191920%      80.808080%
   Costs and expenses:
     Property acquisition costs, operating costs, general
       and administrative expenses and other costs:
         Before payout                                           4.040405%      95.959595%
         After payout (2)                                       19.191920%      80.808080%


   (1)  Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level and 196 limited partner interests owned by
        Pioneer USA.

   (2)  The Partnership reached payout in April 2000.

NOTE 7.      OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       18
   938




                                                              Oil and NGLs          Gas
                                                                 (bbls)            (mcf)
                                                              ------------       ---------

                                                                          
    Net proved reserves at January 1, 1998                       419,589           664,089
    Revisions                                                    (95,538)          (99,794)
    Production                                                   (40,796)          (50,220)
                                                              ----------         ---------

    Net proved reserves at December 31, 1998                     283,255           514,075
    Revisions                                                    292,082           490,347
    Production                                                   (35,770)          (48,774)
                                                              ----------         ---------

    Net proved reserves at December 31, 1999                     539,567           955,648
    Revisions                                                     31,315           (45,195)
    Production                                                   (33,115)          (49,380)
                                                              ----------         ---------

    Net proved reserves at December 31, 2000                     537,767           861,073
                                                              ==========         =========


    As of December 31, 2000, the estimated present value of future net revenues
of proved reserves, calculated using December 31, 2000 prices of $26.63 per
barrel of oil, $13.33 per barrel of NGLs and $7.67 per mcf of gas, discounted at
10% was approximately $4,413,000 and undiscounted was $9,495,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                                   For the years ended December 31,
                                                                --------------------------------------
                                                                   2000          1999         1998
                                                                -----------   -----------  -----------
                                                                             (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                           $   18,453    $   13,256   $    3,115
  Future production costs                                           (8,958)       (7,154)      (2,221)
                                                                  --------      --------     --------

                                                                     9,495         6,102          894
  10% annual discount factor                                        (5,082)       (3,024)        (335)
                                                                  --------      --------     --------

  Standardized measure of discounted future net cash flows      $    4,413    $    3,078   $      559
                                                                 =========     =========     ========


                                       19
   939



                                                          For the years ended December 31,
                                                       --------------------------------------
                                                           2000          1999         1998
                                                       -----------   -----------  -----------
                                                                    (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (635)  $      (262)  $     (147)
    Net changes in prices and production costs              1,865         1,419       (1,151)
    Revisions of previous quantity estimates                  168         2,042         (144)
    Accretion of discount                                     308            56          185
    Changes in production rates, timing and other            (371)         (736)         (32)
                                                         --------     ---------     --------

    Change in present value of future net revenues          1,335         2,519       (1,289)
                                                         --------     ---------     --------

    Balance, beginning of year                              3,078           559        1,848
                                                         --------     ---------     --------

    Balance, end of year                               $    4,413   $     3,078   $      559
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                        
          Plains Marketing, L.P.                      32%           37%             -
          TEPPCO Crude Oil LLC                        22%           23%             -
          Phillips Petroleum Company                  20%           10%             9%
          Genesis Crude Oil, L.P.                      -             -             58%
          Western Gas Resources, Inc.                  6%            7%            23%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
TEPPCO Crude Oil LLC and Phillips Petroleum Company were $25,204, $31,416 and
$21,019, respectively, which are included in the caption "Accounts receivable -
oil and gas sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

                                       20
   940


NOTE 9.      PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Partnership affairs. As managing general partner and
      operator of the Partnership's properties, all production expenses are
      incurred by Pioneer USA and billed to the Partnership. The majority of the
      Partnership's oil and gas revenues are received directly by the
      Partnership, however, a portion of the oil and gas revenue is initially
      received by Pioneer USA prior to being paid to the Partnership. Under the
      limited partnership agreement, the managing general partner pays 1% of the
      Partnership's acquisition, drilling and completion costs and 1% of its
      operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of $6,095,500.
      Pioneer USA is required to contribute amounts equal to 1% of initial
      Partnership capital less commission and offering expenses allocated to the
      limited partners and to contribute amounts necessary to pay costs and
      expenses allocated to it under the Partnership agreement to the extent its
      share of revenues does not cover such costs.

ITEM 9.       CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
                AND FINANCIAL DISCLOSURE
None.

                                       21
   941


                                    PART III


ITEM 10.      DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                            2000                       Position
       ----                            ----                       --------

                                               
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

                                       22
   942

      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.

                                       23
   943

ITEM 11.      EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the limited
partnership agreement, Pioneer USA pays 1% of the Program's acquisition,
drilling and completion costs and 1% of its operating and general and
administrative expenses. In return, Pioneer USA is allocated 1% of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.      SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)   Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 196 limited partner interests at January 1, 2001.

(b)   Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

                                       24
   944

ITEM 13.       CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                        2000          1999           1998
                                                      --------      --------       --------
                                                                          
  Payment of lease operating and supervision
    charges in accordance with standard
    industry operating agreements                     $121,257      $ 137,769      $144,149

  Reimbursement of general and administrative
    expenses                                          $ 27,424      $   8,400      $  9,662


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.

                                       25
   945


                                     PART IV

ITEM 14.      EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                Statements of partners' capital for the years ended December 31,
                   2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.

                                       26
   946


                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                           PARKER & PARSLEY PRODUCING
                           PROPERTIES 87-B, LTD.

Dated: March 29, 2001      By:   Pioneer Natural Resources USA, Inc.
                                 Managing General Partner


                                 By:   /s/ Scott D. Sheffield
                                       -----------------------------
                                       Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                      
/s/ Scott D. Sheffield               President of Pioneer USA                 March 29, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                  Executive Vice President, Chief          March 29, 2001
-------------------------------      Financial Officer and Director of
Timothy L. Dove                      Pioneer USA


/s/ Dennis E. Fagerstone             Executive Vice President and             March 29, 2001
-------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                  Executive Vice President, General        March 29, 2001
-------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                     Executive Vice President - Domestic      March 29, 2001
-------------------------------      Operations and Director of Pioneer
Danny Kellum                         USA


/s/ Rich Dealy                       Vice President and Chief Accounting      March 29, 2001
-------------------------------      Officer of Pioneer USA
Rich Dealy


                                       27
   947


                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----

                                                                          
       3(a)               Amended and Restated Certificate of Limited               -
                          Partnership of Parker & Parsley Producing
                          Properties 87-B, Ltd. incorporated by reference
                          to Exhibit 3a of Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-11193)

       4(a)               Agreement of Limited Partnership of Parker &              -
                          Parsley Producing Properties 87-B, Ltd. incorporated
                          by reference to Exhibit A of Amendment No. 1
                          of the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-11193)

       4(b)               Subscription Agreement incorporated by                    -
                          reference to Exhibit C of Amendment No. 1
                          of the Partnership's Registration Statement
                          on Form S-1 (Registration No. 33-11193)

       4(b)               Power of Attorney incorporated by reference               -
                          to Exhibit B of Amendment No. 1 of the
                          Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-11193)

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit
                          4c of the Partnership's Registration Statement
                          on Form S-1 (Registration No. 33-11193)

      10(b)               Program Agreement incorporated by reference               -
                          to Exhibit B of Amendment No. 1 of the
                          Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-11193)



                                       28
   948



                PARKER & PARSLEY PRODUCING PROPERTIES 87-B, LTD.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  263,792   $  982,604   $  625,861   $  532,606   $  846,163   $  980,232
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   35,017   $  317,255   $   42,277
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  145,081   $  562,621   $  163,148   $ (118,738)  $ (142,439)  $  303,380
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
        partner                    $          $    1,451   $    5,626   $    1,631   $   (1,187)  $   (1,424)  $    3,034
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  143,630   $  556,995   $  161,517   $ (117,551)  $ (141,015)  $  300,346
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
    (loss) per limited
    partnership interest           $          $    11.78   $    45.69   $    13.25   $    (9.64)  $   (11.57)  $    24.64
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $     9.26   $    48.07   $    13.98   $    16.41   $    39.20   $    35.59
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $  930,221   $  860,545   $  892,550   $  878,401   $1,241,161   $1,823,614
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   949


                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

    PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD., A TEXAS LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED        , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS        , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Private Investment 87, Ltd. and supplements the proxy statement/prospectus dated
              , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Private Investment 87, Ltd.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   950

                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                      
Aggregate Initial Investment by the Limited Partners(a)                                                  $     10,480

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                              $     16,514

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)    $      2,921

Merger Value per $1,000 Limited Partner Investment(b), (c)                                               $     278.69

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                            4.08 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                      $     140.53

      --    as of December 31, 2000(c)                                                                   $     144.05

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                        $     260.80

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                          $     270.28

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)            $        177



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion must be counsel other than counsel to Pioneer USA or the partnership.
Both the designated counsel and the legal opinion must be approved by the
limited partners. Pioneer USA has retained __________ of Dallas, Texas for the
purpose of rendering this legal opinion on behalf of the limited partners to
Pioneer USA. The merger proposals include an approval of that counsel and the
form of its opinion. A copy of the opinion is attached as an exhibit to the
merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2037, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   951



                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.

                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   952


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS




                                                     March 31,     December 31,
                                                       2001            2000
                                                   ------------    ------------
                                                    (Unaudited)
                                                             
                     ASSETS
Current assets:
  Cash                                             $     97,591    $     94,943
  Accounts receivable - oil and gas sales               165,875         169,256
                                                   ------------    ------------
        Total current assets                            263,466         264,199
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                7,223,861       7,234,802
Accumulated depletion                                (5,980,855)     (5,959,961)
                                                   ------------    ------------
        Net oil and gas properties                    1,243,006       1,274,841
                                                   ------------    ------------
                                                   $  1,506,472    $  1,539,040
                                                   ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $     19,091    $     14,344

Partners' capital:
  Managing general partner                               14,629          15,002
  Limited partners (262 interests)                    1,472,752       1,509,694
                                                   ------------    ------------
                                                      1,487,381       1,524,696
                                                   ------------    ------------
                                                   $  1,506,472    $  1,539,040
                                                   ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   953



                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                      Three months ended
                                                           March 31,
                                                   -----------------------
                                                      2001         2000
                                                   ----------   ----------
                                                          
Revenues:
  Oil and gas                                      $  294,672   $  240,933
  Interest                                              2,184        1,906
  Gain on disposition of assets                            --       14,938
                                                   ----------   ----------
                                                      296,856      257,777
                                                   ----------   ----------
Costs and expenses:
  Oil and gas production                              111,234      104,648
  General and administrative                            7,701        7,228
  Depletion                                            20,894       21,774
                                                   ----------   ----------
                                                      139,829      133,650
                                                   ----------   ----------
Net income                                         $  157,027   $  124,127
                                                   ==========   ==========
Allocation of net income:
  Managing general partner                         $    1,570   $    1,241
                                                   ==========   ==========
  Limited partners                                 $  155,457   $  122,886
                                                   ==========   ==========
Net income per limited partnership interest        $   593.35   $   469.03
                                                   ==========   ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   954


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                        Managing
                                        general         Limited
                                        partner         partners         Total
                                      ------------    ------------    ------------
                                                             
Balance at January 1, 2001            $     15,002    $  1,509,694    $  1,524,696

    Distributions                           (1,943)       (192,399)       (194,342)

    Net income                               1,570         155,457         157,027
                                      ------------    ------------    ------------

Balance at March 31, 2001             $     14,629    $  1,472,752    $  1,487,381
                                      ============    ============    ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   955



                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                          Three months ended
                                                              March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $  157,027    $  124,127
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                           20,894        21,774
       Gain on disposition of assets                           --       (14,938)
  Changes in assets and liabilities:
       Accounts receivable                                  3,381          (386)
       Accounts payable                                     4,747         4,244
                                                       ----------    ----------
         Net cash provided by operating activities        186,049       134,821
                                                       ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                      (2,767)       (7,441)
  Proceeds from disposition of assets                      13,708        24,834
                                                       ----------    ----------
         Net cash provided by investing activities         10,941        17,393
                                                       ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                         (194,342)     (132,869)
                                                       ----------    ----------
Net increase in cash                                        2,648        19,345
Cash at beginning of period                                94,943       134,914
                                                       ----------    ----------
Cash at end of period                                  $   97,591    $  154,259
                                                       ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   956



                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley Private Investment 87, Ltd. (the "Partnership") was organized
in 1987 as a general partnership under the laws of the State of Texas and was
converted to a Texas limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 22% to $294,672 for the three
months ended March 31, 2001 as compared to $240,933 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 6,848
barrels of oil, 2,038 barrels of natural gas liquids ("NGLs") and 11,385 mcf of
gas were sold, or 10,784 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 6,630 barrels of oil, 2,699 barrels of NGLs and
11,546 mcf of gas were sold, or 11,253 BOEs.

                                        6

   957




The average price received per barrel of oil increased slightly from $27.10 for
the three months ended March 31, 2000 to $27.13 for the same period in 2001. The
average price received per barrel of NGLs increased $4.75, or 32%, from $14.77
for the three months ended March 31, 2000 to $19.52 for the same period in 2001.
The average price received per mcf of gas increased 226% from $1.86 during the
three months ended March 31, 2000 to $6.07 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Gain on disposition of assets of $14,938 recognized during the three months
ended March 31, 2000 were from equipment credits on a well plugged and abandoned
during the prior year.

Costs and Expenses:

Total costs and expenses increased to $139,829 for the three months ended March
31, 2001 as compared to $133,650 for the same period in 2000, an increase of
$6,179 or 5%. This increase was due to increases in production costs and general
and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $111,234 for the three months ended March 31, 2001 and
$104,648 for the same period in 2000 resulting in a $6,586 increase, or 6%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices and additional well maintenance costs incurred to stimulate well
production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 7% from $7,228 for the three months ended March 31, 2000 to $7,701 for
the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $20,894 for the three months ended March 31, 2001 compared to
$21,774 for the same period in 2000, a decrease of $880, or 4%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices, offset by an
increase in oil production of 218 barrels for the three months ended March 31,
2001 as compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $51,228 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $54,017 and a
reduction of $4,270 in working capital, offset by increases in production costs
of $6,586 and G&A expenses of $473. The increase in oil and gas receipts



                                        7

   958


resulted from the increase in commodity prices during 2001 which contributed an
additional $61,985 to oil and gas receipts, offset by $7,968 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs
incurred to stimulate well production. The increase in G&A was primarily due to
an increase in the accrual for tax preparation fees.

Net Cash Provided by Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 related to oil and gas equipment upgrades on active
properties.

Proceeds from disposition of assets of $13,708 and $24,834 were recognized
during the three months ended March 31, 2001 and 2000, respectively. The
proceeds recognized during 2001 were from equipment credits received on an
active property. The proceeds recognized during 2000 were from salvage income
received on a well plugged and abandoned during the prior year.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $194,342, of which $1,943 was distributed to the managing general partner
and $192,399 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $132,869, of which $1,329 was
distributed to the managing general partner and $131,540 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.

                                        8

   959
                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   960




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Private Investment 87, Ltd.
  (A Texas Limited Partnership):

We have audited the balance sheets of Parker & Parsley Private Investment 87,
Ltd. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Private
Investment 87, Ltd. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.



                                             Ernst & Young LLP


Dallas, Texas
March 9, 2001




                                       2
   961


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                                                   2000                1999
                                                                                             ----------------    ----------------
                     ASSETS
                     ------

                                                                                                           
Current assets:
  Cash                                                                                       $       94,943      $       134,914
  Accounts receivable - oil and gas sales                                                           169,256               89,852
                                                                                               ------------        -------------

     Total current assets                                                                           264,199              224,766
                                                                                               ------------        -------------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                                            7,234,802            7,222,781
Accumulated depletion                                                                            (5,959,961)          (5,880,941)
                                                                                               ------------        -------------

          Net oil and gas properties                                                              1,274,841            1,341,840
                                                                                               ------------        -------------

                                                                                             $    1,539,040      $     1,566,606
                                                                                              =============       ==============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                                               $       14,344      $         6,764

Partners' capital:
  Managing general partner                                                                           15,002               15,353
  Limited partners (262 interests)                                                                1,509,694            1,544,489
                                                                                               ------------        -------------

                                                                                                  1,524,696            1,559,842
                                                                                               ------------        -------------

                                                                                             $    1,539,040      $     1,566,606
                                                                                              =============       ==============






   The accompanying notes are an integral part of these financial statements.



                                       3
   962


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                        2000         1999         1998
                                                     ----------   ----------   ----------
                                                                      
Revenues:
   Oil and gas                                       $1,035,947   $  674,794   $  568,014
   Interest                                              10,943        5,922        6,840
   Gain on disposition of assets                         15,201       20,924           --
   Miscellaneous income                                      --           --       27,020
                                                     ----------   ----------   ----------

                                                      1,062,091      701,640      601,874
                                                     ----------   ----------   ----------

Costs and expenses:
   Oil and gas production                               395,308      333,765      357,125
   General and administrative                            31,079       20,244       17,041
   Impairment of oil and gas properties                      --           --      176,587
   Depletion                                             79,020      123,063      259,349
   Abandoned property                                        --       20,129           --
                                                     ----------   ----------   ----------

                                                        505,407      497,201      810,102
                                                     ----------   ----------   ----------

Net income (loss)                                    $  556,684   $  204,439   $ (208,228)
                                                     ==========   ==========   ==========

Allocation of net income (loss):
   Managing general partner                          $    5,567   $    2,044   $   (2,082)
                                                     ==========   ==========   ==========

   Limited partners                                  $  551,117   $  202,395   $ (206,146)
                                                     ==========   ==========   ==========

Net income (loss) per limited partnership interest   $ 2,103.50   $   772.50   $  (786.82)
                                                     ==========   ==========   ==========
















   The accompanying notes are an integral part of these financial statements.



                                       4
   963


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                                            Managing
                                                                            general             Limited
                                                                            partner             partners               Total
                                                                        -------------        --------------       ---------------


                                                                                                         
Partners' capital at January 1, 1998                                    $      20,565        $   2,060,412        $   2,080,977

     Distributions                                                             (2,592)            (256,549)            (259,141)

     Net loss                                                                  (2,082)            (206,146)            (208,228)
                                                                          -----------          -----------          -----------

Partners' capital at December 31, 1998                                         15,891            1,597,717            1,613,608

     Distributions                                                             (2,582)            (255,623)            (258,205)

     Net income                                                                 2,044              202,395              204,439
                                                                          -----------          -----------          -----------

Partners' capital at December 31, 1999                                         15,353            1,544,489            1,559,842

     Distributions                                                             (5,918)            (585,912)            (591,830)

     Net income                                                                 5,567              551,117              556,684
                                                                          -----------          -----------          -----------

Partners' capital at December 31, 2000                                  $      15,002        $   1,509,694        $   1,524,696
                                                                         ============         ============         ============










   The accompanying notes are an integral part of these financial statements.



                                       5
   964


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                                             2000                 1999                1998
                                                                        --------------       --------------      --------------
                                                                                                        
Cash flows from operating activities:
    Net income (loss)                                                   $     556,684        $     204,439       $    (208,228)
    Adjustments to reconcile net income (loss) to
       net cash provided by operating activities:
          Depletion                                                            79,020              123,063             259,349
          Impairment of oil and gas properties                                    -                    -               176,587
          Gain on disposition of assets                                       (15,201)             (20,924)                -
    Changes in assets and liabilities:
          Accounts receivable                                                 (79,404)             (19,909)             44,227
          Accounts payable                                                      7,580                7,671             (37,011)
                                                                          -----------          -----------         -----------

             Net cash provided by operating activities                        548,679              294,340             234,924
                                                                          -----------          -----------         -----------

Cash flows from investing activities:
    Additions to oil and gas properties                                       (12,021)              (1,457)             (6,173)
    Proceeds from asset dispositions                                           15,201               17,049               6,923
                                                                          -----------          -----------         -----------

             Net cash provided by investing activities                          3,180               15,592                 750
                                                                          -----------          -----------         -----------

Cash flows used in financing activities:
    Cash distributions to partners                                           (591,830)            (258,205)           (259,141)
                                                                          -----------          -----------         -----------

Net increase (decrease) in cash                                               (39,971)              51,727             (23,467)
Cash at beginning of year                                                     134,914               83,187             106,654
                                                                          -----------          -----------         -----------

Cash at end of year                                                     $      94,943        $     134,914       $      83,187
                                                                         ============         ============        ============
















   The accompanying notes are an integral part of these financial statements.



                                       6
   965


                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A Texas Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley Private Investment 87, Ltd. (the "Partnership") was
organized in 1987 as a general partnership under the laws of the State of Texas
and was converted to a Texas limited partnership in 1989. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   966

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted and the timing
of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $176,587 related to
its proved oil and gas properties during 1998.



                                       8
   967

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $72,098 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------
                                                                                                         
    Net income (loss) per statements of operations                       $     556,684       $     204,439        $    (208,228)
    Depletion and depreciation provisions for tax
      reporting purposes less than amounts for
      financial reporting purposes                                              73,725             118,474              253,944
    Impairment of oil and gas properties for financial
      reporting purposes                                                           -                   -                176,587
    Salvage income                                                                 -                   -                  6,923
    Other, net                                                                   8,468              (6,345)               1,789
                                                                           -----------         -----------          -----------

             Net income per Federal income tax returns                   $     638,877       $     316,568        $     231,015
                                                                          ============        ============         ============


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------

                                                                                                         
      Development costs                                                  $     12,021        $       1,457        $       6,173
                                                                          ===========         ============         ============


        Capitalized oil and gas properties consist of the following:



                                                                                                   2000                 1999
                                                                                             ----------------     ----------------
                                                                                                            
      Proved properties:
        Property acquisition costs                                                           $       235,953      $      235,953
        Completed wells and equipment                                                              6,998,849           6,986,828
                                                                                               -------------        ------------

                                                                                                   7,234,802           7,222,781
      Accumulated depletion                                                                       (5,959,961)         (5,880,941)
                                                                                               -------------        ------------

        Net oil and gas properties                                                           $     1,274,841      $    1,341,840
                                                                                              ==============       =============




                                       9
   968



NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------
                                                                                                         
      Payment of lease operating and supervision
        charges in accordance with standard industry
        operating agreements                                             $     168,618       $     164,154        $     169,530
      Reimbursement of general and administrative
        expenses                                                         $      27,190       $      13,954        $      13,315


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and the Partnership are parties to the Program agreement.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnership as follows:



                                                                                        Pioneer USA (1)            Partnership
                                                                                        ---------------           -------------
                                                                                                         
        Revenues:
           Proceeds from disposition of depreciable
              properties                                                                     9.09091%              90.90909%
           All other revenues                                                               24.242425%             75.757575%

        Costs and expenses:
           Lease acquisition costs, drilling and completion
              costs and all other costs                                                      9.09091%              90.90909%
           Operating costs, direct costs and general and
              administrative expenses                                                       24.242425%             75.757575%


        (1)     Excludes Pioneer USA's 1% general partner ownership which is
                allocated at the Partnership level.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.









                                       10
   969




                                                                             Oil and NGLs                Gas
                                                                                (bbls)                  (mcf)
                                                                         --------------------     -------------------

                                                                                                 
        Net proved reserves at January 1, 1998                                   593,108                   749,623
        Revisions                                                               (204,355)                 (192,689)
        Production                                                               (42,801)                  (58,036)
                                                                            ------------              ------------

        Net proved reserves at December 31, 1998                                 345,952                   498,898
        Revisions                                                                377,937                   584,604
        Production                                                               (40,495)                  (52,874)
                                                                            ------------              ------------

        Net proved reserves at December 31, 1999                                 683,394                 1,030,628
        Revisions                                                                114,936                   (13,239)
        Production                                                               (35,242)                  (48,307)
                                                                            ------------              ------------

        Net proved reserves at December 31, 2000                                 763,088                   969,082
                                                                            ============              ============


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.67 per barrel of NGLs and $7.76 per mcf of gas,
discounted at 10% was approximately $5,193,000 and undiscounted was $12,461,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                                              For the years ended December 31,
                                                                    -------------------------------------------------------
                                                                          2000                1999               1998
                                                                    ----------------    ----------------   ----------------
                                                                                              (in thousands)
                                                                                                  
Oil and gas producing activities:
   Future cash inflows                                              $        24,836     $       16,945     $         3,765
   Future production costs                                                  (12,375)            (9,216)             (2,895)
                                                                      -------------       ------------       -------------

                                                                             12,461              7,729                 870
   10% annual discount factor                                                (7,268)            (3,837)               (277)
                                                                      -------------       ------------       -------------

   Standardized measure of discounted future net cash flows         $         5,193     $        3,892     $           593
                                                                     ==============      =============      ==============




                                       11
   970



                                                                              For the years ended December 31,
                                                                    -------------------------------------------------------
                                                                          2000                1999               1998
                                                                    ----------------    ----------------   ----------------
                                                                                        (in thousands)
                                                                                                  
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs                    $          (641)    $         (341)    $         (211)
      Net changes in prices and production costs                              1,940              2,019             (1,560)
      Revisions of previous quantity estimates                                  766              2,931               (262)
      Accretion of discount                                                     389                 59                244
      Changes in production rates, timing and other                          (1,153)            (1,369)               (59)
                                                                      -------------       ------------       ------------

      Change in present value of future net revenues                          1,301              3,299             (1,848)
                                                                      -------------       ------------      -------------

      Balance, beginning of year                                              3,892                593              2,441
                                                                      -------------       ------------       ------------

      Balance, end of year                                          $         5,193     $        3,892     $          593
                                                                     ==============      =============      =============


NOTE 8.  MAJOR CUSTOMERS

   The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:


                                                                                2000                1999               1998
                                                                              --------            --------           --------

                                                                                                           
                    Plains Marketing, L.P.                                      42%                 40%                  -
                    Genesis Crude Oil, L.P.                                      -                   -                  46%
                    Western Gas Resources, Inc.                                  3%                  5%                 23%
                    Phillips Petroleum Company                                  17%                 16%                 13%
                    NGTS LLC                                                    10%                  8%                  1%


        At December 31, 2000, the amounts receivable from Plains Marketing,
L.P., Phillips Petroleum Company and NGTS LLC were $34,772, $27,567 and $3,043,
respectively, which are included in the caption "Accounts receivable - oil and
gas sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being




                                       12
   971

        paid to the Partnership. Under the limited partnership agreement, the
        managing general partner pays 1% of the Partnership's acquisition,
        drilling and completion costs and 1% of its operating and general and
        administrative expenses. The managing general partner is also
        responsible for 1% of the guaranty and loan commitment fees. In return,
        it is allocated 1% of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $10,480,000.
        Contributions aggregating $2,822,500 were received directly from the
        partners in cash and the remainder was made available to the limited
        partners by a financial institution. Pioneer USA is required to
        contribute amounts equal to 1% of initial Partnership capital less
        commission and organization and offering costs allocated to the limited
        partners and to contribute amounts necessary to pay costs and expenses
        allocated to it under the Partnership agreement to the extent its share
        of revenues does not cover such costs.




                                       13




   972
                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.
                          (A TEXAS LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
    RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 54% to $1,035,947 for 2000 as
compared to $674,794 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 24,016
barrels of oil, 11,226 barrels of natural gas liquids ("NGLs") and 48,307 mcf of
gas were sold, or 43,293 barrel of oil equivalents ("BOEs"). In 1999, 27,432
barrels of oil, 13,063 barrels of NGLs and 52,874 mcf of gas were sold, or
49,307 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.74, or 76%, from
$16.82 in 1999 to $29.56 in 2000. The average price received per barrel of NGLs
increased $6.76, or 72%, from $9.41 in 1999 to $16.17 in 2000. The average price
received per mcf of gas increased 75% from $1.71 in 1999 to $2.99 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $15,201 during 2000 was attributable to salvage
income received on two wells plugged and abandoned during 1999. Gain on
disposition of assets of $20,924 during 1999 was from salvage value received on
equipment from two wells plugged and abandoned during 1999. Abandoned property
costs of $20,129 were incurred during 1999 related to the plugging of these two
wells.

Total costs and expenses increased in 2000 to $505,407 as compared to $497,201
in 1999, an increase of $8,206, or 2%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by declines in depletion and abandoned property costs.

Production costs were $395,308 in 2000 and $333,765 in 1999, resulting in a
$61,543 increase, or 18%. The increase was due to additional well maintenance
costs incurred to stimulate well production and higher production taxes.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
54% from $20,244 in 1999 to $31,079 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $27,190 in 2000 and $13,954 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $79,020 in 2000 as compared to $123,063 in 1999, representing a
decrease of $44,043, or 36%. This decrease was primarily due to a 114,527
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices and a decline in oil production of 3,416 barrels for the period
ended December 31, 2000 compared to the same period in 1999.


   973

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 19% to $674,794 from
$568,014 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 27,432 barrels of oil,
13,063 barrels of NGLs and 52,874 mcf of gas were sold, or 49,307 BOEs. In 1998,
30,005 barrels of oil, 12,796 barrels of NGLs and 58,036 mcf of gas were sold,
or 52,474 BOEs.

The average price received per barrel of oil increased $3.77, or 29%, from
$13.05 in 1998 to $16.82 in 1999. The average price received per barrel of NGLs
increased $2.86, or 44%, from $6.55 in 1998 to $9.41 in 1999. The average price
received per mcf of gas increased 8% from $1.59 in 1998 to $1.71 in 1999.

Gain on disposition of assets of $20,924 during 1999 was from salvage value
received on equipment from two wells plugged and abandoned during 1999.
Abandoned property costs of $20,129 were incurred during 1999 related to the
plugging of these two wells.

Miscellaneous income of $27,020 during 1998 consisted of the write-off of
amounts previously recorded as accounts payable. These amounts were set aside
until the Partnership reconciled payments for the initial capital contributions.
Once these payments were reconciled, the liability was eliminated and the cash
distributed to the partners.

Total costs and expenses decreased in 1999 to $497,201 as compared to $810,102
in 1998, a decrease of $312,901, or 39%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by increases in abandoned property costs and G&A.

Production costs were $333,765 in 1999 and $357,125 in 1998, resulting in a
$23,360 decrease, or 7%. The decrease was due to declines in well maintenance
costs and ad valorem taxes.

During this period, G&A increased 19% from $17,041 in 1998 to $20,244 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $13,954 in
1999 and $13,315 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $176,587 related to its oil and gas properties during 1998.

Depletion was $123,063 in 1999 compared to $259,349 in 1998, representing a
decrease of $136,286, or 53%. This decrease was the result of an increase in
proved reserves of 239,857 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.



   974

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $254,339 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $366,174 and a decline in abandoned property costs of
$20,129, offset by increases in production costs paid of $61,543, G&A expenses
paid of $10,835 and working capital of $59,586. The increase in oil and gas
receipts resulted from the increase in commodity prices during 2000 which
contributed an additional $510,519 to oil and gas receipts, offset by $144,345
resulting from the decline in production during 2000. The increase in production
costs was primarily due to increased production taxes associated with higher oil
and gas prices and additional well maintenance costs incurred to stimulate well
production. The increase in G&A was primarily due to higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Provided by Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds from asset dispositions of $15,201 received in 2000 were related to
salvage income received on two wells plugged and abandoned during 1999. Proceeds
from asset dispositions of $17,049 received in 1999 were from equipment credits
of $10,226 received on two wells plugged and abandoned during 1999 and equipment
credits of $6,823 received on two active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $591,830, of which $5,918 was
distributed to the managing general partner and $585,912 to the limited
partners. In 1999, cash distributions to the partners were $258,205, of which
$2,582 was distributed to the managing general partner and $255,623 to the
limited partners.








   975



                  PARKER & PARSLEY PRIVATE INVESTMENT 87, LTD.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  240,933   $1,035,947   $  674,794   $  568,014   $  855,114   $1,063,902
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  176,587   $  789,277   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Gain on litigation
    settlement, net                $          $       --   $       --   $       --   $       --   $       --   $  383,911
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  124,127   $  556,684   $  204,439   $ (208,228)  $ (548,407)  $  833,250
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $    1,241   $    5,567   $    2,044   $   (2,082)  $   (5,484)  $    8,333
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  122,886   $  551,117   $  202,395   $ (206,146)  $ (542,923)  $  824,917
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   469.03   $ 2,103.50   $   772.50   $  (786.82)  $(2,072.23)  $ 3,148.54
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   502.06   $ 2,236.31   $   975.66   $   979.19   $ 1,914.87   $ 3,562.66(a)
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $1,572,004   $1,539,040   $1,566,606   $1,622.597   $2,126,977   $3,175,422
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========


----------

(a)  Including litigation settlement per limited partnership interest of
     $1,465.31 in 1996.



   976
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 88-A CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
88-A Conv., L.P., and supplements the proxy statement/prospectus dated         ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 88-A Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   977
                        PARKER & PARSLEY 88-A CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $   3,793

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $   4,250

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $     919
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  245.40

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.21 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --  as of March 31, 2001  (c)                                                          $  149.96

        --  as of December 31, 2000  (c)                                                       $  150.71

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  228.01

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  238.25

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     142
(c), (f)


----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   978

                        PARKER & PARSLEY 88-A CONV., L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   979



                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS






                                                                      March 31,        December 31,
                                                                        2001               2000
                                                                     -----------       -----------
                                                                     (Unaudited)
                                                                                 
                 ASSETS


Current assets:
  Cash                                                               $    48,004       $    54,706
  Accounts receivable - oil and gas sales                                 81,080            65,812
                                                                     -----------       -----------
        Total current assets                                             129,084           120,518
                                                                     -----------       -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                                 2,964,986         2,964,986
Accumulated depletion                                                 (2,511,790)       (2,502,477)
                                                                     -----------       -----------
        Net oil and gas properties                                       453,196           462,509
                                                                     -----------       -----------
                                                                     $   582,280       $   583,027
                                                                     ===========       ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                                       $     7,660       $     5,544

Partners' capital:
  Managing general partner                                                 5,818             5,847
  Limited partners (3,793 interests)                                     568,802           571,636
                                                                     -----------       -----------
                                                                         574,620           577,483
                                                                     -----------       -----------
                                                                     $   582,280       $   583,027
                                                                     ===========       ===========



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        2

   980



                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)






                                                    Three months ended
                                                         March 31,
                                                 ----------------------------
                                                    2001             2000
                                                 -----------      -----------
                                                            
Revenues:
  Oil and gas                                    $   133,532      $    89,122
  Interest                                               957              840
  Gain on disposition of assets                           --               76
                                                 -----------      -----------
                                                     134,489           90,038
                                                 -----------      -----------
Costs and expenses:
  Oil and gas production                              44,328           43,761
  General and administrative                           4,006            2,674
  Depletion                                            9,313            7,515
                                                 -----------      -----------
                                                      57,647           53,950
                                                 -----------      -----------
Net income                                       $    76,842      $    36,088
                                                 ===========      ===========
Allocation of net income:
  Managing general partner                       $       768      $       361
                                                 ===========      ===========
  Limited partners                               $    76,074      $    35,727
                                                 ===========      ===========
Net income per limited partnership interest      $     20.06      $      9.42
                                                 ===========      ===========



         The financial information included herein has been prepared by the
  managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   981



                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)








                                Managing
                                general         Limited
                                partner         partners         Total
                                --------        --------        -------



                                                       
Balance at January 1, 2001      $ 5,847        $571,636        $577,483

    Distributions                  (797)        (78,908)        (79,705)

    Net income                      768          76,074          76,842
                                -------        --------        --------

Balance at March 31, 2001       $ 5,818        $568,802        $574,620
                                =======        ========        ========









         The financial information included herein has been prepared by the
  managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        4

   982



                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)






                                                                Three months ended
                                                                     March 31,
                                                          -------------------------------
                                                              2001               2000
                                                          ------------       ------------
                                                                       
Cash flows from operating activities:
  Net income                                              $     76,842       $     36,088
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                                 9,313              7,515
       Gain on disposition of assets                                --                (76)
  Changes in assets and liabilities:
       Accounts receivable                                     (15,268)             5,674
       Accounts payable                                          2,116                949
                                                          ------------       ------------
           Net cash provided by operating activities            73,003             50,150
                                                          ------------       ------------
Cash flows from investing activities:
  Additions to oil and gas properties                               --             (1,022)
  Proceeds from disposition of assets                               --                 76
                                                          ------------       ------------
           Net cash used in investing activities                    --               (946)
                                                          ------------       ------------
Cash flows used in financing activities:
  Cash distributions to partners                               (79,705)           (47,796)
                                                          ------------       ------------
Net increase (decrease) in cash                                 (6,702)             1,408
Cash at beginning of period                                     54,706             66,104
                                                          ------------       ------------
Cash at end of period                                     $     48,004       $     67,512
                                                          ============       ============






         The financial information included herein has been prepared by the
  managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        5

   983

                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 88-A Conv., L.P. (the "Partnership") was organized in 1988 as a
general partnership under the laws of the State of Texas and was converted to a
Delaware limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 50% to $133,532 for the three
months ended March 31, 2001 as compared to $89,122 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 2,956 barrels
of oil, 927 barrels of natural gas liquids ("NGLs") and 8,645 mcf of gas were
sold, or 5,324 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 2,309 barrels of oil, 1,187 barrels of NGLs and 4,685 mcf of gas
were sold, or 4,277 BOEs. Of the increase, 1,183 BOEs are attributable to two

                                        6

   984



wells reaching payout pursuant to the terms of the farmout agreements which
increased the Partnership's net revenue interest in the wells.

The average price received per barrel of oil decreased $1.92, or 7%, from $27.90
for the three months ended March 31, 2000 to $25.98 for the same period in 2001.
The average price received per barrel of NGLs increased $4.19, or 30%, from
$13.93 for the three months ended March 31, 2000 to $18.12 for the same period
in 2001. The average price received per mcf of gas increased 167% from $1.73
during the three months ended March 31, 2000 to $4.62 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $76 was recognized during the three months
ended March 31, 2000 resulting from equipment credits received on one fully
depleted well.

Costs and Expenses:

Total costs and expenses increased to $57,647 for the three months ended March
31, 2001 as compared to $53,950 for the same period in 2000, an increase of
$3,697, or 7%. This increase was due to increases in depletion, general and
administrative expenses ("G&A") and production costs.

Production costs were $44,328 for the three months ended March 31, 2001 and
$43,761 for the same period in 2000 resulting in a $567 increase, or 1%. The
increase was primarily due to increased lease operating and production taxes
attributable to the wells that reached payout pursuant to the terms of the
farmout agreements as noted above and higher production taxes associated with
higher oil and gas prices, offset by decreases in well maintenance and workover
costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 50% from $2,674 for the three months ended March 31, 2000 to $4,006
for the same period in 2001, primarily due to a higher percentage of the
managing general partners' G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues attributable to
commodity prices and the two wells reaching payout as noted above and an
increase in the accrual for tax preparation fees.

Depletion was $9,313 for the three months ended March 31, 2001 compared to
$7,515 for the same period in 2000, an increase of $1,798, or 24%. This increase
was primarily due to an increase in oil production of 647 barrels, which was
principally due to the two wells reaching payout as noted above, for the period
ended March 31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $22,853 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $44,527, offset



                                        7

   985


by increases in production costs of $567, G&A expenses of $1,332 and working
capital of $19,775. The increase in oil and gas receipts resulted from the
increase in commodity prices during 2001 which contributed an additional $14,119
to oil and gas receipts and $30,408 resulting from an increase in production
during 2001. The increase in production costs was primarily due to increased
production taxes associated with higher oil and gas prices, offset by a decrease
in well maintenance and workover costs. The increase in G&A was primarily due to
a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from asset dispositions of $76 received during the three months ended
March 31, 2000 were due to equipment credits received on one fully depleted
well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $79,705, of which $797 was distributed to the managing general partner and
$78,908 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $47,796, of which $478 was distributed to the
managing general partner and $47,318 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.

                                        8



   986



                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   987



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 88-A Conv., L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 88-A Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 88-A Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                             Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   988


                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                             2000                 1999
                                                        ---------------     ---------------
                     ASSETS

                                                                      
Current assets:
   Cash                                                $        54,706      $       66,104
   Accounts receivable - oil and gas sales                      65,812              47,494
                                                         -------------       -------------

            Total current assets                               120,518             113,598
                                                         -------------       -------------

Oil and gas properties - at cost, based on the
   successful efforts accounting method                      2,964,986           2,962,354
Accumulated depletion                                       (2,502,477)         (2,471,979)
                                                         -------------       -------------

            Net oil and gas properties                         462,509             490,375
                                                         -------------       -------------

                                                       $       583,027     $       603,973
                                                        ==============      ==============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable - affiliate                        $         5,544     $         6,800

Partners' capital:
   Managing general partner                                      5,847               6,043
   Limited partners (3,793 interests)                          571,636             591,130
                                                         -------------       -------------

                                                               577,483             597,173
                                                         -------------       -------------

                                                       $       583,027     $       603,973
                                                        ==============      ==============



The accompanying notes are an integral part of these financial statements.



                                       3
   989


                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                       2000        1999        1998
                                                     ---------   ---------   ---------
                                                                    
Revenues:
  Oil and gas                                        $ 418,514   $ 280,717   $ 227,119
  Interest                                               4,636       2,657       2,966
  Gain on disposition of assets                             76          --       1,875
  Other income                                              --          --          29
                                                     ---------   ---------   ---------

                                                       423,226     283,374     231,989
                                                     ---------   ---------   ---------

Costs and expenses:
  Oil and gas production                               160,855     129,227     149,228
  General and administrative                            12,419       8,448       6,995
  Impairment of oil and gas properties                      --          --     118,823
  Depletion                                             30,498      48,743     108,077
                                                     ---------   ---------   ---------

                                                       203,772     186,418     383,123
                                                     ---------   ---------   ---------

Net income (loss)                                    $ 219,454   $  96,956   $(151,134)
                                                     =========   =========   =========

Allocation of net income (loss):
  Managing general partner                           $   2,195   $     970   $  (1,511)
                                                     =========   =========   =========

  Limited partners                                   $ 217,259   $  95,986   $(149,623)
                                                     =========   =========   =========

Net income (loss) per limited partnership interest   $   57.28   $   25.31   $  (39.45)
                                                     =========   =========   =========



The accompanying notes are an integral part of these financial statements.



                                       4
   990


                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                         Managing
                                          general     Limited
                                          partner     partners        Total
                                         ---------    ---------    ---------

                                                       
Partners' capital at January 1, 1998     $   8,622    $ 846,560    $ 855,182

   Distributions                            (1,069)    (105,839)    (106,908)

   Net loss                                 (1,511)    (149,623)    (151,134)
                                         ---------    ---------    ---------

Partners' capital at December 31, 1998       6,042      591,098      597,140

   Distributions                              (969)     (95,954)     (96,923)

   Net income                                  970       95,986       96,956
                                         ---------    ---------    ---------

Partners' capital at December 31, 1999       6,043      591,130      597,173

   Distributions                            (2,391)    (236,753)    (239,144)

   Net income                                2,195      217,259      219,454
                                         ---------    ---------    ---------

Partners' capital at December 31, 2000   $   5,847    $ 571,636    $ 577,483
                                         =========    =========    =========



The accompanying notes are an integral part of these financial statements.



                                       5
   991


                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                            2000         1999         1998
                                                          ---------    ---------    ---------

                                                                        
Cash flows from operating activities:
    Net income (loss)                                     $ 219,454    $  96,956    $(151,134)
    Adjustments to reconcile net income (loss) to
       net cash provided by operating activities:
          Impairment of oil and gas properties                   --           --      118,823
          Depletion                                          30,498       48,743      108,077
          Gain on disposition of assets                         (76)          --       (1,875)
    Changes in assets and liabilities:
          Accounts receivable                               (18,318)     (25,396)      25,872
          Accounts payable                                   (1,256)       1,462       (4,318)
                                                          ---------    ---------    ---------

              Net cash provided by operating activities     230,302      121,765       95,445
                                                          ---------    ---------    ---------

Cash flows used in investing activities:
    Additions to oil and gas properties                      (2,632)      (3,474)      (5,091)
    Proceeds from disposition of assets                          76           --        4,856
                                                          ---------    ---------    ---------

              Net cash used in investing activities          (2,556)      (3,474)        (235)
                                                          ---------    ---------    ---------

Cash flows used in financing activities:
    Cash distributions to partners                         (239,144)     (96,923)    (106,908)
                                                          ---------    ---------    ---------

Net increase (decrease) in cash                             (11,398)      21,368      (11,698)
Cash at beginning of year                                    66,104       44,736       56,434
                                                          ---------    ---------    ---------

Cash at end of year                                       $  54,706    $  66,104    $  44,736
                                                          =========    =========    =========



The accompanying notes are an integral part of these financial statements.



                                       6
   992


                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 88-A Conv., L.P. (the "Partnership") was organized in
1988 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1989. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   993


        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.  IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $118,823 related to
its proved oil and gas properties during 1998.




                                       8
   994


NOTE 4.  INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $78,614 greater than the tax basis at December 31, 2000.

         The following is a reconciliation of net income (loss) per statements
of operations with the net income per Federal income tax returns for the years
ended December 31:




                                                                              2000                1999                1998
                                                                         --------------      --------------      --------------
                                                                                                       
      Net income (loss) per statements of operations                     $     219,454       $      96,956       $    (151,134)
      Depletion and depreciation amounts for tax
        reporting purposes less than provisions for
        financial reporting purposes                                            27,183              45,310             104,973
      Impairment of oil and gas properties for financial
        reporting purposes                                                         -                   -               118,823
      Other, net                                                                  (622)               (961)              4,070
                                                                           -----------         -----------         -----------

            Net income per Federal income tax returns                    $     246,015       $     141,305       $      76,732
                                                                          ============        ============        ============


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:




                                                                              2000                1999                 1998
                                                                         --------------      --------------       --------------
                                                                                                       
      Development costs                                                 $        2,632       $       3,474        $      5,091
                                                                         =============        ============         ===========



      Capitalized oil and gas properties consist of the following:





                                                                 2000                 1999
                                                           ----------------     ----------------
                                                                         
      Proved properties:
        Property acquisition costs                         $       143,766     $       143,766
        Completed wells and equipment                            2,821,220           2,818,588
                                                             -------------       -------------

                                                                 2,964,986           2,962,354
      Accumulated depletion                                     (2,502,477)         (2,471,979)
                                                             -------------       -------------

            Net oil and gas properties                     $       462,509     $       490,375
                                                            ==============      ==============





                                       9
   995



NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                                              2000                1999                1998
                                                                         --------------      --------------      --------------
                                                                                                      
      Payment of lease operating and supervision
        charges in accordance with standard industry
        operating agreements                                             $     64,830        $      62,056       $      63,244

      Reimbursement of general and administrative expenses               $     10,947        $       5,872       $       5,659


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 88-A, L.P. and the Partnership (the "Partnerships") are parties
to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:




                                                                                         Pioneer USA (1)          Partnerships (2)
                                                                                        -----------------         ----------------

                                                                                                        
    Revenues:
       Proceeds from disposition of depreciable
          properties                                                                         9.09091%                90.90909%
       All other revenues                                                                   24.242425%               75.757575%

    Costs and expenses:
       Lease acquisition costs, drilling and completion
          costs and all other costs                                                          9.09091%                90.90909%
       Operating costs, direct costs and general and
          administrative expenses                                                           24.242425%               75.757575%


       (1)     Excludes Pioneer USA's 1% general partner ownership which is
               allocated at the Partnership level and 50 limited partner
               interests owned by Pioneer USA.

       (2)     The allocation between the Partnership and Parker & Parsley
               88-A, L.P. is 22.674558% and 77.325442%, respectively.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.





                                                            Oil and NGLs                  Gas
                                                                (bbls)                   (mcf)
                                                          ---------------          ----------------
                                                                             
      Net proved reserves at January 1, 1998                     245,336                   365,368
      Revisions                                                  (90,082)                  (90,310)
      Production                                                 (16,899)                  (25,367)
                                                          --------------            --------------

      Net proved reserves at December 31, 1998                   138,355                   249,691
      Revisions                                                  118,130                   203,398
      Production                                                 (17,052)                  (27,417)
                                                          --------------            --------------

      Net proved reserves at December 31, 1999                   239,433                   425,672
      Revisions                                                    3,043                   (86,940)
      Production                                                 (14,604)                  (21,399)
                                                          --------------            --------------

      Net proved reserves at December 31, 2000                   227,872                   317,333
                                                          ==============            ==============




                                       10
   996



        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.95 per barrel of NGLs and $7.75 per mcf of gas,
discounted at 10% was approximately $1,723,000 and undiscounted was $3,515,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.






                                                                   For the years ended December 31,
                                                                  ----------------------------------
                                                                     2000       1999       1998
                                                                    -------    -------    -------
                                                                            (in thousands)
                                                                                
Oil and gas producing activities:
   Future cash inflows                                              $ 7,404    $ 5,900    $ 1,511
   Future production costs                                           (3,889)    (3,311)    (1,087)
                                                                    -------    -------    -------

                                                                      3,515      2,589        424
   10% annual discount factor                                        (1,792)    (1,238)      (161)
                                                                    -------    -------    -------

   Standardized measure of discounted future net cash flows         $ 1,723    $ 1,351    $   263
                                                                    =======    =======    =======




                                       11
   997





                                                                     For the years ended December 31,
                                                          ---------------------------------------------------
                                                                2000                1999               1998
                                                          ---------------     --------------     --------------
                                                                              (in thousands)
                                                                                       
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs          $          (258)    $         (151)    $          (78)
      Net changes in prices and production costs                      694                658               (635)
      Revisions of previous quantity estimates                        (75)               786               (131)
      Accretion of discount                                           135                 26                104
      Changes in production rates, timing and other                  (124)              (231)               (37)
                                                            -------------       ------------       ------------

      Change in present value of future net revenues                  372              1,088               (777)
                                                            -------------       ------------       ------------

      Balance, beginning of year                                    1,351                263              1,040
                                                            -------------       ------------       ------------

      Balance, end of year                                $         1,723     $        1,351     $          263
                                                           ==============      =============      =============



NOTE 8.  MAJOR CUSTOMERS

   The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:




                                                           2000              1999                1998
                                                         --------          --------            --------
                                                                                      
                   Plains Marketing, L.P.                     54%                50%                 -
                   NGTS LLC                                    9%                10%                 -
                   Genesis Crude Oil, L.P.                     -                  -                 55%
                   Western Gas Resources, Inc.                 3%                 6%                22%



        At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
was $21,731, which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being



                                       12
   998



        paid to the Partnership. Under the limited partnership agreement, the
        managing general partner pays 1% of the Partnership's acquisition,
        drilling and completion costs and 1% of its operating and general and
        administrative expenses. In return, it is allocated 1% of the
        Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $3,793,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.



                                       13
   999




                        PARKER & PARSLEY 88-A CONV., L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
     RESULTS OF OPERATIONS

2000 compared to 1999

The Partnership's oil and gas revenues increased 49% to $418,514 for 2000 as
compared to $280,717 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 9,403
barrels of oil, 5,201 barrels of natural gas liquids ("NGLs") and 21,399 mcf of
gas were sold, or 18,171 barrel of oil equivalents ("BOEs"). In 1999, 9,977
barrels of oil, 7,075 barrels of NGLs and 27,417 mcf of gas were sold, or 21,622
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.37, or 73%, from
$16.91 in 1999 to $29.28 in 2000. The average price received per barrel of NGLs
increased $6.00, or 65%, from $9.30 in 1999 to $15.30 in 2000. The average price
received per mcf of gas increased 77% from $1.69 in 1999 to $2.99 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $76 was recognized in 2000 resulting from
equipment credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $203,772 as compared to $186,418
in 1999, an increase of $17,354, or 9%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $160,855 in 2000 and $129,227 in 1999, resulting in a
$31,628 increase, or 24%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
and workover costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
47% from $8,448 in 1999 to $12,419 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $10,947 in 2000 and $5,872 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $30,498 in 2000 as compared to $48,743 in 1999, representing a
decrease of $18,245, or 37%. This decrease was primarily due to a 13,403 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.


   1000


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 24% to $280,717 from
$227,119 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production. In 1999, 9,977 barrels of oil, 7,075
barrels of NGLs and 27,417 mcf of gas were sold, or 21,622 BOEs. In 1998, 10,890
barrels of oil, 6,009 barrels of NGLs and 25,367 mcf of gas were sold, or 21,127
BOEs.

The average price received per barrel of oil increased $3.32, or 24%, from
$13.59 in 1998 to $16.91 in 1999. The average price received per barrel of NGLs
increased $2.73, or 42%, from $6.57 in 1998 to $9.30 in 1999. The average price
received per mcf of gas increased 8% from $1.56 in 1998 to $1.69 in 1999.

A gain on disposition of assets of $1,875 was recognized during 1998 for credits
received from the disposal of oil and gas equipment on a fully depleted well.

Total costs and expenses decreased in 1999 to $186,418 as compared to $383,123
in 1998, a decrease of $196,705, or 51%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $129,227 in 1999 and $149,228 in 1998, resulting in a
$20,001 decrease, or 13%. The decrease was due to declines in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes due to
increased oil and gas revenues.

During this period, G&A increased 21% from $6,995 in 1998 to $8,448 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $5,872 in
1999 and $5,659 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $118,823 related to its oil and gas properties during 1998.

Depletion was $48,743 in 1999 compared to $108,077 in 1998, representing a
decrease of $59,334, or 55%. This decrease was the result of an increase in
proved reserves of 72,170 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum Industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.


   1001


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $108,537 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $139,776 and a decline in working capital of $4,360,
offset by increases in production costs paid of $31,628 and G&A expenses paid of
$3,971. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2000 which contributed an additional $203,232 to oil and
gas receipts, offset by $63,456 resulting from the decline in production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices and well maintenance and
workover costs incurred to stimulate well production. The increase in G&A was
primarily due to higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds from asset dispositions of $76 received during 2000 were due to
equipment credits received on one fully depleted well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $239,144, of which $2,391 was
distributed to the managing general partner and $236,753 to the limited
partners. In 1999, cash distributions to the partners were $96,923, of which
$969 was distributed to the managing general partner and $95,954 to the limited
partners.









   1002


                        PARKER & PARSLEY 88-A CONV., L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   89,122   $  418,514   $  280,717   $  227,119   $  339,522   $  413,924
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  118,823   $  205,188   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   36,088   $  219,454   $   96,956   $ (151,134)  $  (97,307)  $  175,901
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      361   $    2,195   $      970   $   (1,511)  $     (973)  $    1,759
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   35,727   $  217,259   $   95,986   $ (149,623)  $  (96,334)  $  174,142
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     9.42   $    57.28   $    25.31   $   (39.45)  $   (25.40)  $    45.91
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    12.48   $    62.42   $    25.30   $    27.90   $    50.68   $    57.12
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  593,214   $  583,027   $  603,973   $  602,478   $  864,838   $1,154,160
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1003
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 88-A, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
88-A, L.P., and supplements the proxy statement/prospectus dated      , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 88-A, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1004
                           PARKER & PARSLEY 88-A, L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $  12,935

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $  14,494

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   3,139
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  245.95

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.21 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --  as of March 31, 2001  (c)                                                          $  150.48

        --  as of December 31, 2000  (c)                                                       $  151.23

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  228.56

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  238.80

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     142
(c), (f)


----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   1005



                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-19659-01


                           PARKER & PARSLEY 88-A, L.P.
             (Exact name of Registrant as specified in its charter)

                  Delaware                              75-2225738
      ----------------------------------          ----------------------
       (State or other jurisdiction of               (I.R.S. Employer
       incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas       75039
----------------------------------------------------------------     ----------
           (Address of principal executive offices)                  (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                         if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]





   1006



                           PARKER & PARSLEY 88-A, L.P.

                                TABLE OF CONTENTS




                                                                       Page
                                                                
                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000.......................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000............................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001.....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000............................    6

           Notes to Financial Statements..............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations......................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K...........................   10

           Signatures.................................................   11





                                        2
   1007



                           PARKER & PARSLEY 88-A, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                      March 31,     December 31,
                                                        2001            2000
                                                    ------------    ------------
                                                    (Unaudited)
                                                              
                 ASSETS

Current assets:
  Cash                                              $    181,063    $    193,491
  Accounts receivable - oil and gas sales                266,590         224,465
                                                    ------------    ------------
         Total current assets                            447,653         417,956
                                                    ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                10,111,281      10,111,281
Accumulated depletion                                 (8,566,166)     (8,534,409)
                                                    ------------    ------------
         Net oil and gas properties                    1,545,115       1,576,872
                                                    ------------    ------------
                                                    $  1,992,768    $  1,994,828
                                                    ============    ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $     26,364    $     18,724

Partners' capital:
  Managing general partner                                19,906          20,003
  Limited partners (12,935 interests)                  1,946,498       1,956,101
                                                    ------------    ------------
                                                       1,966,404       1,976,104
                                                    ------------    ------------
                                                    $  1,992,768    $  1,994,828
                                                    ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   1008



                           PARKER & PARSLEY 88-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                     Three months ended
                                                          March 31,
                                                 ---------------------------
                                                     2001           2000
                                                 ------------   ------------
                                                          

Revenues:
   Oil and gas                                   $    455,361   $    304,068
   Interest                                             3,334          3,115
   Gain on disposition of assets                           --            259
                                                 ------------   ------------
                                                      458,695        307,442
                                                 ------------   ------------
Costs and expenses:
   Oil and gas production                             151,163        149,276
   General and administrative                          13,661          9,122
   Depletion                                           31,757         25,581
                                                 ------------   ------------
                                                      196,581        183,979
                                                 ------------   ------------
Net income                                       $    262,114   $    123,463
                                                 ============   ============
Allocation of net income:
   Managing general partner                      $      2,621   $      1,235
                                                 ============   ============
   Limited partners                              $    259,493   $    122,228
                                                 ============   ============
Net income per limited partnership interest      $      20.06   $       9.45
                                                 ============   ============





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.




                                        4

   1009



                           PARKER & PARSLEY 88-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                   Managing
                                    general        Limited
                                    partner        partners         Total
                                 ------------    ------------    ------------
                                                        
Balance at January 1, 2001       $     20,003    $  1,956,101    $  1,976,104

    Distributions                      (2,718)       (269,096)       (271,814)

    Net income                          2,621         259,493         262,114
                                 ------------    ------------    ------------

Balance at March 31, 2001        $     19,906    $  1,946,498    $  1,966,404
                                 ============    ============    ============





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5
   1010



                           PARKER & PARSLEY 88-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                            Three months ended
                                                                 March 31,
                                                         ------------------------
                                                            2001           2000
                                                         ----------    ----------
                                                                 

Cash flows from operating activities:
  Net income                                             $  262,114    $  123,463
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                             31,757        25,581
       Gain on disposition of assets                             --          (259)
  Changes in assets and liabilities:
       Accounts receivable                                  (42,125)        2,811
       Accounts payable                                       7,640         3,421
                                                         ----------    ----------
          Net cash provided by operating activities         259,386       155,017
                                                         ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                            --        (3,485)
  Proceeds from disposition of assets                            --           259
                                                         ----------    ----------
          Net cash used in investing activities                  --        (3,226)
                                                         ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                           (271,814)     (162,998)
                                                         ----------    ----------
Net decrease in cash                                        (12,428)      (11,207)
Cash at beginning of period                                 193,491       215,801
                                                         ----------    ----------
Cash at end of period                                    $  181,063    $  204,594
                                                         ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        6

   1011



                           PARKER & PARSLEY 88-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley 88-A, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 50% to $455,361 for the three
months ended March 31, 2001 as compared to $304,068 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 10,082
barrels of oil, 3,156 barrels of natural gas liquids ("NGLs") and 29,495 mcf of
gas were sold, or 18,154 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 7,878 barrels of oil, 4,068 barrels of NGLs and


                                        7

   1012



15,987 mcf of gas were sold, or 14,611 BOEs. Of the increase, 3,880 BOEs are
attributable to two wells reaching payout pursuant to the terms of the farmout
agreements which increased the Partnership's net revenue interest in the wells.

The average price received per barrel of oil decreased $1.92, or 7%, from $27.90
for the three months ended March 31, 2000 to $25.98 for the same period in 2001.
The average price received per barrel of NGLs increased $4.19, or 30%, from
$13.93 for the three months ended March 31, 2000 to $18.12 for the same period
in 2001. The average price received per mcf of gas increased 167% from $1.73
during the three months ended March 31, 2000 to $4.62 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $259 was recognized during the three months
ended March 31, 2000 resulting from equipment credits received on one fully
depleted well.

Costs and Expenses:

Total costs and expenses increased to $196,581 for the three months ended March
31, 2001 as compared to $183,979 for the same period in 2000, an increase of
$12,602, or 7%. The increase was due to increases in depletion, general and
administrative expenses ("G&A") and production costs.

Production costs were $151,163 for the three months ended March 31, 2001 and
$149,276 for the same period in 2000, resulting in a $1,887 increase, or 1%. The
increase was primarily due to increased lease operating and production taxes
attributable to the wells that reached payout pursuant to the terms of the
farmout agreements as noted above and higher production taxes associated with
higher oil and gas prices, offset by decreases in well maintenance and workover
costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 50% from $9,122 for the three months ended March 31, 2000 to $13,661
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues attributable to
commodity prices and the two wells reaching payout as noted above and an
increase in the accrual for tax preparation fees.

Depletion was $31,757 for the three months ended March 31, 2001 as compared to
$25,581 for the same period in 2000, an increase of $6,176, or 24%. This
increase was primarily due to an increase in oil production of 2,204 barrels,
which was principally due to the two wells reaching payout as noted above, for
the three months ended March 31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $104,369 for the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $151,512 in oil and gas sales receipts,


                                        8

   1013



offset by increases in production costs of $1,887, G&A expenses of $4,539 and
working capital of $40,717. The increase in oil and gas receipts resulted from
the increase in commodity prices during 2001 which contributed an additional
$48,394 to oil and gas receipts and $103,118 resulting from an increase in
production during 2001. The increase in production costs was primarily due to
increased production taxes associated with higher oil and gas prices, offset by
a decrease in well maintenance and workover costs. The increase in G&A was
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2000 were related to upgrades of oil and gas equipment on active
properties.

Proceeds from disposition of assets of $259 received during the three months
ended March 31, 2000 were due to equipment credits received on one fully
depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $271,814, of which $2,718 was distributed to the managing general partner
and $269,096 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $162,998, of which $1,630 was
distributed to the managing general partner and $161,368 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.


                                        9

   1014



                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)    Exhibits - none

(b)    Reports on Form 8-K - none.






                                       10
   1015


                           PARKER & PARSLEY 88-A, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                          PARKER & PARSLEY 88-A, L.P.

                                 By:      Pioneer Natural Resources USA, Inc.
                                           Managing General Partner



Dated:  May 9, 2001              By:      /s/ Rich Dealy
                                          -----------------------------------
                                          Rich Dealy, Vice President
                                            and Chief Accounting Officer









                                       11

   1016
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-19659-01


                           PARKER & PARSLEY 88-A, L.P.
             (Exact name of Registrant as specified in its charter)

              DELAWARE                                       75-2225738
-------------------------------                         ----------------------
(State or other jurisdiction of                           (I.R.S. Employer
 incorporation or organization)                         Identification Number)




                                                                       
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS              75039
----------------------------------------------------------------          ------------
             (Address of principal executive offices)                      (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$12,762,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 12,935.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None
PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

   1017
                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 88-A, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 12,935 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segments other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 54% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and






                                       2
   1018



ruptures and discharges of toxic substances or gases that could expose the
Partnership to substantial liability due to pollution and other environmental
damages. Although the Partnership believes that its business operations do not
impair environmental quality and that its costs of complying with any applicable
environmental regulations are not currently significant, the Partnership cannot
predict what, if any, effect these environmental regulations may have on its
current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located in
the Spraberry Trend area of West Texas were acquired by the Partnership,
resulting in the Partnership's participation in the drilling of 40 oil and gas
wells. At December 31, 2000, 39 wells were producing with one well plugged and
abandoned.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.






                                       3
   1019
                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
            DISTRIBUTIONS

At March 8, 2001, the Partnership had 12,935 outstanding limited partnership
interests held of record by 981 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations, are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $807,385 and $327,220, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                      2000         1999          1998          1997         1996
                                  -----------   ----------    ----------    ----------   ----------
                                                                         
Operating results:
-----------------
  Oil and gas sales               $ 1,428,374   $  957,278   $   774,533   $ 1,157,862  $ 1,411,568
                                   ==========    =========    ==========    ==========   ==========

  Impairment of oil and
    gas properties                $        -    $       -    $   405,308   $  699,976   $        -
                                   ==========    =========    ==========    =========    ==========

  Net income (loss)               $   749,290   $  331,033   $  (514,812)  $ (331,171)  $   600,634
                                   ==========    =========    ==========    =========    ==========

  Allocation of net income
    (loss):
    Managing general partner      $     7,493   $    3,310   $    (5,148)  $   (3,312)  $     6,006
                                   ==========    =========    ==========    =========    ==========

    Limited partners              $   741,797   $  327,723   $  (509,664)  $ (327,859)  $   594,628
                                   ==========    =========    ==========    =========    ==========

  Limited partners' net
    income (loss) per limited
    partnership interest          $     57.35   $    25.34   $    (39.40)  $   (25.35)  $     45.97
                                   ==========    =========    ==========    =========    ==========

   Limited partners' cash
    distributions per limited
    partnership interest          $     62.42   $    25.30   $     27.90   $    50.68    $    57.12
                                   ==========    =========    ==========    =========     =========

At year end:
-----------
  Identifiable assets             $ 1,994,828   $ 2,065,363  $ 2,059,502   $ 2,953,618   $3,940,216
                                   ==========    ==========   ==========    ==========    =========









                                       4
   1020


ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
            RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 49% to $1,428,374 for 2000 as
compared to $957,278 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decrease in production. In 2000, 32,063
barrels of oil, 17,745 barrels of natural gas liquids ("NGLs") and 72,965 mcf of
gas were sold, or 61,969 barrel of oil equivalents ("BOEs"). In 1999, 34,020
barrels of oil, 24,121 barrels of NGLs and 93,498 mcf of gas were sold, or
73,724 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.37, or 73%, from
$16.91 in 1999 to $29.28 in 2000. The average price received per barrel of NGLs
increased $6.00, or 65%, from $9.30 in 1999 to $15.30 in 2000. The average price
received per mcf of gas increased 77% from $1.69 in 1999 to $2.99 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $259 was recognized in 2000 resulting from
equipment credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $695,576 as compared to $635,628
in 1999, an increase of $59,948, or 9%. The increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $548,561 in 2000 and $440,670 in 1999, resulting in an
increase of $107,891, or 24%. The increase was primarily due to additional well
maintenance costs incurred to stimulate well production and higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
50% from $28,692 in 1999 to $42,987 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $37,340 in 2000 and $20,027 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $104,028 in 2000 as compared to $166,266 in 1999, representing a
decrease of $62,238, or 37%. This decrease was primarily due to a 45,809 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 24% to $957,278 from
$774,533 in 1998.






                                       5
   1021
The increase in revenues resulted from higher average prices received and an
increase in production. In 1999, 34,020 barrels of oil, 24,121 barrels of NGLs
and 93,498 mcf of gas were sold, or 73,724 BOEs. In 1998, 37,135 barrels of oil,
20,500 barrels of NGLs and 86,501 mcf of gas were sold, or 72,052 BOEs.

The average price received per barrel of oil increased $3.32, or 24%, from
$13.59 in 1998 to $16.91 in 1999. The average price received per barrel of NGLs
increased $2.73, or 42%, from $6.57 in 1998 to $9.30 in 1999. The average price
received per mcf of gas increased 8% from $1.56 in 1998 to $1.69 in 1999.

A gain on disposition of assets of $6,393 was recognized in 1998 for credits
received from the disposal of oil and gas equipment on a fully depleted well.

Total costs and expenses decreased in 1999 to $635,628 as compared to $1,306,368
in 1998, a decrease of $670,740, or 51%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A expenses.

Production costs were $440,670 in 1999 and $508,919 in 1998, resulting in a
$68,249 decrease, or 13%. The decrease was due to reductions in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes due to
increased oil and gas revenues.

During this period, G&A increased 22% from $23,611 in 1998 to $28,692 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $20,027 in
1999 and $19,297 in 1998 for G&A incurred on behalf of the Partnership.


In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $405,308 related to its oil and gas properties during 1998.

Depletion was $166,266 in 1999 compared to $368,530 in 1998, representing a
decrease of $202,264, or 55%. This decrease was the result of an increase in
proved reserves of 246,048 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but






                                       6
   1022


to a lesser extent, market prices for natural gas declined. During 1999 and
2000, the Organization of Petroleum Exporting Countries ("OPEC") and certain
other crude oil exporting nations announced reductions in their planned export
volumes. Those announcements, together with the enactment of the announced
reductions in export volumes, had a positive impact on world oil prices, as have
overall natural gas supply and demand fundamentals on North American natural gas
prices. Although the favorable commodity price environment and stable field
service cost environment is expected to continue during 2001, there is no
assurance that commodity prices will not return to a less favorable level or
that field service costs will not escalate in the future, both of which could
negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $401,553 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $477,946 and a decline in working capital of $45,793,
offset by increases in production costs paid of $107,891 and G&A expenses paid
of $14,295. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2000 which contributed an additional $694,183 to oil and
gas receipts, offset by $216,237 resulting from the decline in production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices and well maintenance and
workover costs incurred to stimulate well production. The increase in G&A was
primarily due to higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $259 received in 2000 were due to equipment
credits received on one fully depleted well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $815,540, of which $8,155 was
distributed to the managing general partner and $807,385 to the limited
partners. In 1999, cash distributions to the partners were $330,525, of which
$3,305 was distributed to the managing general partner and $327,220 to the
limited partners.







                                       7
   1023



ITEM 8.       FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS




                                                                                       Page
                                                                                       ----
                                                                                      
Financial Statements of Parker & Parsley 88-A, L.P.:
  Independent Auditors' Report......................................................      9
  Balance Sheets as of December 31, 2000 and 1999...................................     10
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998.............................................................     11
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998................................................     12
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998.............................................................     13
  Notes to Financial Statements.....................................................     14








                                       8
   1024



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 88-A, L.P.
 (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 88-A, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 88-A, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       9
   1025



                         PARKER & PARSLEY 88-A, L.P.
                       (A Delaware Limited Partnership)

                                BALANCE SHEETS
                                 December 31




                                                                   2000             1999
                                                                ----------       ----------
             ASSETS
             ------
                                                                          
Current assets:
  Cash                                                         $   193,491      $   215,801
  Accounts receivable - oil and gas sales                          224,465          177,635
                                                                ----------       ----------

        Total current assets                                       417,956          393,436
                                                                ----------       ----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                          10,111,281       10,102,308
Accumulated depletion                                           (8,534,409)      (8,430,381)
                                                                ----------       ----------

        Net oil and gas properties                               1,576,872        1,671,927
                                                                ----------       ----------

                                                               $ 1,994,828      $ 2,065,363
                                                                ==========       ==========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                 $    18,724      $    23,009

Partners' capital:
  Managing general partner                                          20,003           20,665
  Limited partners (12,935 interests)                            1,956,101        2,021,689
                                                                ----------       ----------

                                                                 1,976,104        2,042,354
                                                                ----------       ----------
                                                               $ 1,994,828      $ 2,065,363
                                                                ==========       ==========













   The accompanying notes are an integral part of these financial statements.








                                       10
   1026



                         PARKER & PARSLEY 88-A, L.P.
                       (A Delaware Limited Partnership)

                           STATEMENTS OF OPERATIONS
                       For the years ended December 31






                                                       2000         1999           1998
                                                     --------     --------       --------
                                                                       
Revenues:
  Oil and gas                                      $1,428,374    $  957,278     $  774,533
  Interest                                             16,233         9,383         10,531
  Gain on disposition of assets                           259            -           6,393
  Other                                                    -             -              99
                                                    ---------     ---------      ---------

                                                    1,444,866       966,661        791,556
                                                    ---------     ---------      ---------

Costs and expenses:
  Oil and gas production                              548,561       440,670        508,919
  General and administrative                           42,987        28,692         23,611
  Impairment of oil and gas properties                     -             -         405,308
  Depletion                                           104,028       166,266        368,530
                                                    ---------     ---------      ---------

                                                      695,576       635,628      1,306,368
                                                    ---------     ---------      ---------

Net income (loss)                                  $  749,290    $  331,033     $ (514,812)
                                                    =========     =========      =========

Allocation of net income (loss):
  Managing general partner                         $    7,493    $    3,310     $   (5,148)
                                                    =========     =========      =========

  Limited partners                                 $  741,797    $  327,723     $ (509,664)
                                                    =========     =========      =========

Net income (loss) per limited partnership
  interest                                         $    57.35    $    25.34     $   (39.40)
                                                    =========     =========      =========














   The accompanying notes are an integral part of these financial statements.






                                       11
   1027



                         PARKER & PARSLEY 88-A, L.P.
                       (A Delaware Limited Partnership)

                       STATEMENTS OF PARTNERS' CAPITAL






                                                   Managing
                                                   general        Limited
                                                   partner        partners         Total
                                                   --------      ----------     ----------
                                                                      
Partners' capital at January 1, 1998              $  29,454     $ 2,891,783    $ 2,921,237

  Distributions                                      (3,646)       (360,933)      (364,579)

  Net loss                                           (5,148)       (509,664)      (514,812)
                                                   --------      ----------     ----------

Partners' capital at December 31, 1998               20,660       2,021,186      2,041,846

  Distributions                                      (3,305)       (327,220)      (330,525)

  Net income                                          3,310         327,723        331,033
                                                   --------      ----------     ----------

Partners' capital at December 31, 1999               20,665       2,021,689      2,042,354

  Distributions                                      (8,155)       (807,385)      (815,540)

  Net income                                          7,493         741,797        749,290
                                                   --------      ----------     ----------

Partners' capital at December 31, 2000            $  20,003     $ 1,956,101    $ 1,976,104
                                                   ========      ==========     ==========











   The accompanying notes are an integral part of these financial statements.








                                       12
   1028



                         PARKER & PARSLEY 88-A, L.P.
                       (A Delaware Limited Partnership)

                           STATEMENTS OF CASH FLOWS
                       For the years ended December 31






                                                      2000          1999           1998
                                                    --------      ---------      --------
                                                                       
Cash flows from operating activities:
  Net income (loss)                                $ 749,290     $  331,033     $(514,812)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
    Impairment of oil and gas properties                  -              -        405,308
    Depletion                                        104,028        166,266       368,530
    Gain on disposition of assets                       (259)            -         (6,393)
  Changes in assets and liabilities:
    Accounts receivable                              (46,830)      (102,261)       78,333
    Accounts payable                                  (4,285)         5,353       (14,725)
                                                    --------      ---------      --------

    Net cash provided by operating activities        801,944        400,391       316,241
                                                    --------      ---------      --------

Cash flows from investing activities:
  Additions to oil and gas properties                 (8,973)       (11,847)      (17,362)
  Proceeds from asset dispositions                       259             -         16,559
                                                    --------      ---------      --------

    Net cash used in investing activities             (8,714)       (11,847)         (803)
                                                    --------      ---------      --------

Cash flows used in financing activities:
  Cash distributions to partners                    (815,540)      (330,525)     (364,579)
                                                    --------      ---------      --------

Net increase (decrease) in cash                      (22,310)        58,019       (49,141)
Cash at beginning of year                            215,801        157,782       206,923
                                                    --------      ---------      --------

Cash at end of year                                $ 193,491     $  215,801     $ 157,782
                                                    ========      =========      ========














   The accompanying notes are an integral part of these financial statements.






                                       13
   1029



                         PARKER & PARSLEY 88-A, L.P.
                       (A Delaware Limited Partnership)

                        NOTES TO FINANCIAL STATEMENTS
                       December 31, 2000, 1999 and 1998

NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 88-A, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.







                                       14
   1030

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

     In accordance with SFAS 121, the Partnership reviews its proved oil and gas
properties for impairment whenever events and circumstances indicate a decline
in the recoverability of the carrying value of the Partnership's oil and gas
properties. The Partnership has estimated the expected future cash flows of its
oil and gas properties as of December 31, 2000, 1999 and 1998, based on proved
reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $405,308 related to
its proved oil and gas properties during 1998.

NOTE 4.    INCOME TAXES

     The financial statement basis of the Partnership's net assets and
liabilities was $267,761 greater than the tax basis at December 31, 2000.







                                       15
   1031

     The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                           2000          1999           1998
                                                         --------      --------      ---------
                                                                           
    Net income (loss) per statements of operations      $ 749,290     $ 331,033     $ (514,812)
    Depletion and depreciation for tax reporting
      purposes less than provisions for financial
      reporting purposes                                   92,722       154,558        357,942
    Impairment of oil and gas properties for financial
      reporting purposes                                       -             -         405,308
    Other, net                                             (2,176)       (2,693)        13,320
                                                         --------      --------      ---------

            Net income per Federal income tax
               returns                                  $ 839,836     $ 482,898     $  261,758
                                                         ========      ========      =========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                    --------      ---------      --------
                                                                       
      Development costs                            $   8,973     $   11,847     $  17,362
                                                    ========      =========      ========



      Capitalized oil and gas properties consist of the following:



                                                                 2000              1999
                                                              ----------        ----------
                                                                         
     Proved properties:
       Property acquisition costs                            $   490,279       $   490,279
       Completed wells and equipment                           9,621,002         9,612,029
                                                              ----------        ----------

                                                              10,111,281        10,102,308
     Accumulated depletion                                    (8,534,409)       (8,430,381)
                                                              ----------        ----------

          Net oil and gas properties                         $ 1,576,872       $ 1,671,927
                                                              ==========        ==========









                                       16
   1032



NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                     2000          1999           1998
                                                   ---------     ----------     ---------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 221,084     $ 211,623      $ 215,684

    Reimbursement of general and administrative
      expenses                                     $  37,340     $  20,027      $  19,297


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 88-A Conv., L.P. and the Partnership (the "Partnerships") are
parties to the Program agreement.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                                  Pioneer USA (1)     Partnerships (2)
                                                                 ----------------     ----------------
                                                                                
    Revenues:
      Proceeds from disposition of depreciable properties              9.09091%           90.90909%
      All other revenues                                             24.242425%          75.757575%
    Costs and expenses:
      Lease acquisition costs, drilling and completion
        costs and all other costs                                      9.09091%           90.90909%
      Operating costs, direct costs and general and
        administrative expenses                                      24.242425%          75.757575%


   (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
         at the Partnership level and 173 limited partner interests owned by
         Pioneer USA.

   (2)   The allocation between the Partnership and Parker & Parsley 88-A
         Conv., L.P. is 77.325442% and 22.674558%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.








                                       17
   1033




                                                              Oil and NGLs        Gas
                                                                 (bbls)          (mcf)
                                                              -------------   -----------
                                                                        
    Net proved reserves at January 1, 1998                           836,39     1,245,602
    Revisions                                                      (307,084)     (307,863)
    Production                                                      (57,635)      (86,501)
                                                              -------------   -----------

    Net proved reserves at December 31, 1998                        471,675       851,238
    Revisions                                                       402,731       693,436
    Production                                                      (58,141)      (93,498)
                                                              -------------   -----------

    Net proved reserves at December 31, 1999                        816,265     1,451,176
    Revisions                                                        10,578      (296,099)
    Production                                                      (49,808)      (72,965)
                                                              -------------   -----------

    Net proved reserves at December 31, 2000                        777,035     1,082,112
                                                              =============   ===========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.95 per barrel of NGLs and $7.75 per mcf of gas,
discounted at 10% was approximately $5,875,000 and undiscounted was $11,988,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                                   For the years ended December 31,
                                                                 ------------------------------------
                                                                   2000          1999         1998
                                                                 ---------     ---------    ---------
                                                                             (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                           $   25,247    $   20,115   $    5,153
  Future production costs                                          (13,258)      (11,289)      (3,707)
                                                                 ---------     ---------    ---------

                                                                    11,989         8,826        1,446
  10% annual discount factor                                        (6,114)       (4,222)        (550)
                                                                 ---------     ---------    ---------

  Standardized measure of discounted future net cash flows      $    5,875    $    4,604    $     896
                                                                 =========     =========     ========










                                       18
   1034




                                                          For the years ended December 31,
                                                        ------------------------------------
                                                           2000         1999         1998
                                                        ---------    ----------    ---------
                                                                   (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (880)  $      (517)  $     (266)
    Net changes in prices and production costs              2,367         2,244       (2,296)
    Revisions of estimated future development costs            -             -          (237)
    Revisions of previous quantity estimates                 (253)        2,680         (474)
    Accretion of discount                                     460            89          355
    Changes in production rates, timing and other            (423)         (788)         269
                                                        ---------    ----------    ---------

    Change in present value of future net revenues          1,271         3,708       (2,649)
                                                        ---------    ----------    ---------

    Balance, beginning of year                              4,604           896        3,545
                                                        ---------    ----------    ---------

    Balance, end of year                               $    5,875   $     4,604   $      896
                                                        =========    ==========    =========


NOTE 8.    MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------
                                                                          
           Plains Marketing, L.P.                     54%            50%            -
           NGTS LLC                                    9%            10%            3%
           Genesis Crude Oil, L.P.                     -              -            55%
           Western Gas Resources, Inc.                 3%             6%           22%


      At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $74,114, which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.



NOTE 9.    PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the limited partnership agreement, the managing general









                                       19
   1035

      partner pays 1% of the Partnership's acquisition, drilling and completion
      costs and 1% of its operating and general and administrative expenses. In
      return, it is allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of
      $12,935,000. Pioneer USA is required to contribute amounts equal to 1% of
      initial Partnership capital less commission and offering expenses
      allocated to the limited partners and to contribute amounts necessary to
      pay costs and expenses allocated to it under the Partnership agreement to
      the extent its share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
            FINANCIAL DISCLOSURE

None.







                                       20
   1036

                                    PART III

ITEM 10.   DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                     Age at
                                  December 31,
       Name                           2000                       Position
       ----                           ----                       --------
                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.







                                       21
   1037




      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.







                                       22
   1038

ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 173 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.









                                       23
   1039

ITEM 13.   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                                     2000           1999           1998
                                                   ---------      ---------      ---------
                                                                        
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 221,084      $ 211,623      $ 215,684

    Reimbursement of general and administrative
      expenses                                     $  37,340      $  20,027      $  19,297


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.










                                       24
   1040



                                     PART IV

ITEM 14.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)  1.  Financial statements

         The following are filed as part of this Report:

                Independent Auditors' Report

                Balance sheets as of December 31, 2000 and 1999

                Statements of operations for the years ended December 31,
                  2000, 1999 and 1998

                Statements of partners' capital for the years ended December
                  31, 2000, 1999 and 1998

                Statements of cash flows for the years ended December 31, 2000,
                  1999 and 1998

                Notes to financial statements

     2.  Financial statement schedules

         All financial statement schedules have been omitted since the required
         information is in the financial statements or notes thereto, or is not
         applicable nor required.

(b)  Reports on Form 8-K

None.

(c)  Exhibits

     The exhibits listed on the accompanying index to exhibits are filed or
     incorporated by reference as part of this Report.







                                       25
   1041



                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 88-A, L.P.

Dated: March 23, 2001               By:   Pioneer Natural Resources USA, Inc.
                                           Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                -------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 23, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 23, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 23, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 23, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 23, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 23, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy









                                       26
   1042



                         PARKER & PARSLEY 88-A, L.P.

                              INDEX TO EXHIBITS


      The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----
                                                                           
     3(a)                 Amended and Restated Certificate and                     -
                          Agreement of Limited Partnership of
                          Parker & Parsley 88-A, L.P. incorporated
                          by reference to Exhibit A of Amendment
                          No. 1 of the Partnership's Registration
                          Statement on Form S-1 (Registration No.
                          33-19659)

     4(b)                 Form of Subscription Agreement and                       -
                          Power of Attorney incorporated by reference
                          to Exhibit D of the Partnership's Registration
                          Statement on Form S-1 (Registration No.
                          33-19659) (hereinafter called the Partnership's
                          Registration Statement)

     4(c)                 Specimen Certificate of Limited Partnership              -
                          Interest incorporated by reference to Exhibit
                          D of the Partnership's Registration Statement

    10(b)                 Exploration and Development Program                      -
                          Agreement incorporated by reference to
                          Exhibit C of the Partnership's Registration
                          Statement









                                       27
   1043




                           PARKER & PARSLEY 88-A, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  304,068   $1,428,374   $  957,278   $  774,533   $1,157,862   $1,411,568
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  405,308   $  699,976   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  123,463   $  749,290   $  331,033   $ (514,812)  $ (331,171)  $  600,634
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
         partner                   $          $    1,235   $    7,493   $    3,310   $   (5,148)  $   (3,312)  $    6,006
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  122,228   $  741,797   $  327,723   $ (509,664)  $ (327,859)  $  594,628
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     9.45   $    57.35   $    25.34   $   (39.40)  $   (25.35)  $    45.97
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    12.48   $    62.42   $    25.30   $    27.90   $    50.68   $    57.12
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $2,029,249   $1,994,828   $2,065,363   $2,059,502   $2,953,618   $3,940,216
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1044
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 88-B CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
88-B Conv., L.P., and supplements the proxy statement/prospectus dated        ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 88-B Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1045

                        PARKER & PARSLEY 88-B CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $   3,636

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $   4,108

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   1,160
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  320.83

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.34 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  138.09

        --        as of December 31, 2000  (c)                                                 $  144.77

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  299.13

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  311.40

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     145
(c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                      -2-
   1046


                        PARKER & PARSLEY 88-B CONV., L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   1047



                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS




                                                     March 31,     December 31,
                                                       2001            2000
                                                   ------------    ------------
                                                    (Unaudited)
                                                            
                 ASSETS

Current assets:
  Cash                                             $     55,640    $     58,050
  Accounts receivable - oil and gas sales                64,690          80,619
                                                   ------------    ------------
        Total current assets                            120,330         138,669
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                2,824,417       2,824,029
Accumulated depletion                                (2,430,649)     (2,424,313)
                                                   ------------    ------------
        Net oil and gas properties                      393,768         399,716
                                                   ------------    ------------
                                                   $    514,098    $    538,385
                                                   ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $      6,925    $      6,684

Partners' capital:
  Managing general partner                                5,062           5,308
  Limited partners (3,636 interests)                    502,111         526,393
                                                   ------------    ------------
                                                        507,173         531,701
                                                   ------------    ------------
                                                   $    514,098    $    538,385
                                                   ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2

   1048



                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                       Three months ended
                                                            March 31,
                                                     ----------   ----------
                                                        2001         2000
                                                     ----------   ----------
                                                            
Revenues:
  Oil and gas                                        $  132,577   $  117,117
  Interest                                                1,102          847
                                                     ----------   ----------
                                                        133,679      117,964
                                                     ----------   ----------
Costs and expenses:
  Oil and gas production                                 42,392       36,623
  General and administrative                              3,314        3,627
  Depletion                                               6,336        8,004
                                                     ----------   ----------
                                                         52,042       48,254
                                                     ----------   ----------
Net income                                           $   81,637   $   69,710
                                                     ==========   ==========
Allocation of net income:
  Managing general partner                           $      816   $      697
                                                     ==========   ==========
  Limited partners                                   $   80,821   $   69,013
                                                     ==========   ==========
Net income per limited partnership interest          $    22.23   $    18.98
                                                     ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3

   1049


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)



                                        Managing
                                         general        Limited
                                         partner        partners         Total
                                      ------------    ------------    ------------
                                                             
Balance at January 1, 2001            $      5,308    $    526,393    $    531,701

    Distributions                           (1,062)       (105,103)       (106,165)

    Net income                                 816          80,821          81,637
                                      ------------    ------------    ------------

Balance at March 31, 2001             $      5,062    $    502,111    $    507,173
                                      ============    ============    ============





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4

   1050


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                          Three months ended
                                                                March 31,
                                                       ------------------------
                                                         2001           2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $   81,637    $   69,710
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            6,336         8,004
  Changes in assets and liabilities:
       Accounts receivable                                 15,929         1,534
       Accounts payable                                       241         1,248
                                                       ----------    ----------
         Net cash provided by operating activities        104,143        80,496
                                                       ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                        (601)         (764)
  Proceeds from disposition of assets                         213            --
                                                       ----------    ----------
         Net cash used in investing activities               (388)         (764)
                                                       ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                         (106,165)      (66,905)
                                                       ----------    ----------
Net increase (decrease) in cash                            (2,410)       12,827
Cash at beginning of period                                58,050        59,846
                                                       ----------    ----------
Cash at end of period                                  $   55,640    $   72,673
                                                       ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5

   1051


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 88-B Conv., L.P. (the "Partnership") was organized in 1988 as a
general partnership under the laws of the State of Texas and was converted to a
Delaware limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 13% to $132,577 for the three
months ended March 31, 2001 as compared to $117,117 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 2,743
barrels of oil, 940 barrels of natural gas liquids ("NGLs") and 3,500 mcf of gas
were sold, or 4,266 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 3,346 barrels of oil, 1,321 barrels of NGLs and 5,699 mcf
of gas were sold, or 5,617 BOEs.


                                        6

   1052



Of the decrease, 1,125 BOEs are attributable to three wells reaching payout
pursuant to the terms of the farmout agreements which reduced the Partnership's
net revenue interest in the wells.

The average price received per barrel of oil increased $3.39, or 13%, from
$26.41 for the three months ended March 31, 2000 to $29.80 for the same period
in 2001. The average price received per barrel of NGLs increased $5.63, or 39%,
from $14.34 for the three months ended March 31, 2000 to $19.97 for the same
period in 2001. The average price received per mcf of gas increased 428% from
$1.73 during the three months ended March 31, 2000 to $9.14 for the same period
in 2001. The market price for oil and gas has been extremely volatile in the
past decade, and management expects a certain amount of volatility to continue
in the foreseeable future. The Partnership may therefore sell its future oil and
gas production at average prices lower or higher than that received during the
three months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $52,042 for the three months ended March
31, 2001 as compared to $48,254 for the same period in 2000, an increase of
$3,788, or 8%. This increase was due to an increase in production costs, offset
by declines in depletion and general and administrative expenses ("G&A").

Production costs were $42,392 for the three months ended March 31, 2001 and
$36,623 for the same period in 2000 resulting in a $5,769 increase, or 16%. The
increase in production costs was primarily due to higher production taxes
associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production, offset by a decline in
lease operating and production taxes attributable to the wells that reached
payout pursuant to the terms of a farmout agreements as noted above.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
decreased 9% from $3,627 for the three months ended March 31, 2000 to $3,314 for
the same period in 2001.

Depletion was $6,336 for the three months ended March 31, 2001 compared to
$8,004 for the same period in 2000, a decrease of $1,668, or 21%. This decrease
was primarily due to a decrease in oil production of 603 barrels for the period
ended March 31, 2001 as compared to the same period in 2000 and positive
revisions to proved reserves during the three months ended March 31, 2001 as a
result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $23,647 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $15,715 and
reductions in working capital of $13,388 and G&A expenses of $313, offset by an



                                        7

   1053


increase in production costs of $5,769. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $61,429 to oil and gas receipts, offset by $45,714 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance and
workover costs incurred to stimulate well production.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from disposition of assets of $213 recognized during the three months
ended March 31, 2001 were due to equipment credits received on active
properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $106,165, of which $1,062 was distributed to the managing general partner
and $105,103 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $66,905, of which $669 was distributed
to the managing general partner and $66,236 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   " Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.



                                        8



   1054






                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999




   1055





                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 88-B Conv., L.P.
 (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 88-B Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 88-B Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                          Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                        2

   1056



                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                                      2000             1999
                                                                                 --------------  --------------
                                                                                           
                 ASSETS
                 ------

Current assets:
  Cash                                                                          $     58,050     $     59,846
  Accounts receivable - oil and gas sales                                             80,619           47,842
                                                                                 -----------      -----------

         Total current assets                                                        138,669          107,688
                                                                                 -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                             2,824,029        2,894,900
Accumulated depletion                                                             (2,424,313)      (2,470,345)
                                                                                 -----------      -----------

         Net oil and gas properties                                                  399,716          424,555
                                                                                 -----------      -----------

                                                                                $    538,385     $    532,243
                                                                                 ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                                  $      6,684     $      8,672

Partners' capital:
  Managing general partner                                                             5,308            5,227
  Limited partners (3,636 interests)                                                 526,393          518,344
                                                                                 -----------      -----------

                                                                                     531,701          523,571
                                                                                 -----------      -----------

                                                                                $    538,385     $    532,243
                                                                                 ===========      ===========






   The accompanying notes are an integral part of these financial statements.


                                        3

   1057


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                                  2000              1999             1998
                                                              -----------       -----------      -----------

                                                                                        
Revenues:
  Oil and gas                                                 $   535,228       $   291,390      $   234,942
  Interest                                                          5,043             2,697            3,084
  Gain on disposition of assets                                     7,186               -                 63
                                                               ----------        ----------       ----------

                                                                  547,457           294,087          238,089
                                                               ----------        ----------       ----------

Costs and expenses:
  Oil and gas production                                          174,071           146,805          158,704
  General and administrative                                       15,875             8,615            7,091
  Impairment of oil and gas properties                                -                 -            156,111
  Depletion                                                        27,450            42,399          114,895
  Abandoned property                                                2,755               -                -
                                                               ----------        ----------       ----------

                                                                  220,151           197,819          436,801
                                                               ----------        ----------       ----------

Net income (loss)                                             $   327,306       $    96,268      $  (198,712)
                                                               ==========        ==========       ==========

Allocation of net income (loss):
  Managing general partner                                    $     3,273       $       963      $    (1,987)
                                                               ==========        ==========       ==========

  Limited partners                                            $   324,033       $    95,305      $  (196,725)
                                                               ==========        ==========       ==========

Net income (loss) per limited partnership interest            $     89.12       $     26.21      $    (54.10)
                                                               ==========        ==========       ==========






   The accompanying notes are an integral part of these financial statements.

                                        4


   1058


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                               Managing
                                                                general          Limited
                                                                partner          partners           Total
                                                              -----------      ------------      -----------

                                                                                        
Partners' capital at January 1, 1998                          $     8,195      $    812,239      $   820,434

    Distributions                                                    (882)          (87,329)         (88,211)

    Net loss                                                       (1,987)         (196,725)        (198,712)
                                                               ----------       -----------       ----------

Partners' capital at December 31, 1998                              5,326           528,185          533,511

    Distributions                                                  (1,062)         (105,146)        (106,208)

    Net income                                                        963            95,305           96,268
                                                               ----------       -----------       ----------

Partners' capital at December 31, 1999                              5,227           518,344          523,571

    Distributions                                                  (3,192)         (315,984)        (319,176)

    Net income                                                      3,273           324,033          327,306
                                                               ----------       -----------       ----------

Partners' capital at December 31, 2000                        $     5,308      $    526,393      $   531,701
                                                               ==========       ===========       ==========






   The accompanying notes are an integral part of these financial statements.

                                        5


   1059



                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                                 2000             1999               1998
                                                             ------------      -----------       -----------

                                                                                        
Cash flows from operating activities:
    Net income (loss)                                        $    327,306      $    96,268       $   (198,712)
    Adjustments to reconcile net income (loss) to
      net cash provided by operating activities:
         Impairment of oil and gas properties                         -                -              156,111
         Depletion                                                 27,450           42,399            114,895
         Gain on disposition of assets                             (7,186)             -                  (63)
    Changes in assets and liabilities:
         Accounts receivable                                      (32,777)         (18,949)            10,720
         Accounts payable                                          (1,988)           1,575             (4,516)
                                                              -----------       ----------        -----------

            Net cash provided by operating activities             312,805          121,293             78,435
                                                              -----------       ----------        -----------

Cash flows from investing activities:
    Additions to oil and gas properties                            (2,611)          (3,396)            (6,118)
    Proceeds from disposition of assets                             7,186            4,369                 63
                                                              -----------       ----------        -----------

            Net cash provided by (used in)
               investing activities                                 4,575              973             (6,055)
                                                              -----------       ----------        -----------

Cash flows used in financing activities:
    Cash distributions to partners                               (319,176)        (106,208)           (88,211)
                                                              -----------       ----------        -----------

Net increase (decrease) in cash                                    (1,796)          16,058            (15,831)
Cash at beginning of year                                          59,846           43,788             59,619
                                                              -----------       ----------        -----------

Cash at end of year                                          $     58,050      $    59,846       $     43,788
                                                              ===========       ==========        ===========






   The accompanying notes are an integral part of these financial statements.

                                        6


   1060


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 88-B Conv., L.P. (the "Partnership") was organized in
1988 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1989. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

       The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

       Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.


                                        7


   1061


        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $156,111 related to
its proved oil and gas properties during 1998.


                                        8


   1062


NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $30,771 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                  2000             1999              1998
                                                              -----------       -----------      -----------

                                                                                        
    Net income (loss) per statements of operations            $   327,306       $    96,268      $  (198,712)
    Depletion and depreciation provisions for tax reporting
       purposes less than amounts for financial reporting
       purposes                                                    23,646            38,232          111,242
    Impairment of oil and gas properties for financial
       reporting purposes                                             -                 -            156,111
    Other, net                                                     (1,011)            3,526              477
                                                               ----------        ----------       ----------

            Net income per Federal income tax returns         $   349,941       $   138,026      $    69,118
                                                               ==========        ==========       ==========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                  2000              1999             1998
                                                              -----------       -----------      -----------

                                                                                        
       Development costs                                      $     2,611       $     3,396      $     6,118
                                                               ==========        ==========       ==========


       Capitalized oil and gas properties consist of the following:



                                                                                     2000             1999
                                                                                -------------    -------------
                                                                                           
       Proved properties:
            Property acquisition costs                                          $     173,265    $     178,368
            Completed wells and equipment                                           2,650,764        2,716,532
                                                                                 ------------     ------------

                                                                                    2,824,029        2,894,900
       Accumulated depletion                                                       (2,424,313)      (2,470,345)
                                                                                 ------------     ------------

                  Net oil and gas properties                                    $     399,716    $     424,555
                                                                                 ============     ============



                                        9

   1063


NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                             2000             1999               1998
                                                         -----------       -----------       -----------

                                                                                    
    Payment of lease operating and supervision
       charges in accordance with standard
       industry operating agreements                     $    64,694       $    63,771       $    61,312

    Reimbursement of general and administrative
       expenses                                          $    13,920       $     5,293       $     5,608


        The Partnership participates in oil and gas activities through an
income tax partnership (the "Program") pursuant to the Program agreement.
Pioneer USA, Parker & Parsley 88-B, L.P. and the Partnership (the
"Partnerships") are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA
and the Partnerships as follows:



                                                                            Pioneer USA (1)      Partnerships (2)
                                                                          -------------------  --------------------

                                                                                           
    Revenues:
      Proceeds from disposition of depreciable
         properties                                                             9.09091%            90.90909%
      All other revenues                                                      24.242425%           75.757575%

    Costs and expenses:
      Lease acquisition costs, drilling and completion
         costs                                                                  9.09091%            90.90909%
      Operating costs, direct costs and general and
         administrative expenses                                              24.242425%           75.757575%


     (1)   Excludes Pioneer USA's 1% general partner ownership which is
           allocated at the Partnership level and 20 limited partner interests
           owned by Pioneer USA.

     (2)   The allocation between the Partnership and Parker & Parsley 88-B,
           L.P. is 28.880064% and 71.119936%, respectively.


NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the
Partnership's reserves are proved developed and located within the United
States. The Partnership's reserves are based on an evaluation prepared by
Williamson Petroleum Consultants, Inc., an independent petroleum consultant,
using criteria established by the Securities and Exchange Commission.




                                                                            Oil and NGLs               Gas
                                                                               (bbls)                 (mcf)
                                                                            ------------          ------------

                                                                                             
       Net proved reserves at January 1, 1998                                    214,797               248,651
       Revisions                                                                 (87,571)              (74,562)
       Production                                                                (17,610)              (21,214)
                                                                            ------------          ------------

       Net proved reserves at December 31, 1998                                  109,616               152,875
       Revisions                                                                 152,579               224,938
       Production                                                                (16,986)              (23,221)
                                                                            ------------          ------------

       Net proved reserves at December 31, 1999                                  245,209               354,592
       Revisions                                                                  46,611                24,276
       Production                                                                (18,572)              (21,781)
                                                                            ------------          ------------

       Net proved reserves at December 31, 2000                                  273,248               357,087
                                                                            ============          ============



                                       10


   1064


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.59 per barrel of NGLs and $7.85 per mcf of gas,
discounted at 10% was approximately $2,098,000 and undiscounted was $4,398,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                                          For the years ended December 31,
                                                                   ---------------------------------------------
                                                                       2000             1999            1998
                                                                   ------------     ------------    ------------
                                                                                   (in thousands)
                                                                                           
Oil and gas producing activities:
   Future cash inflows                                             $      8,963     $      6,119    $      1,201
   Future production costs                                               (4,565)          (3,521)           (930)
                                                                    -----------      -----------     -----------

                                                                          4,398            2,598             271
   10% annual discount factor                                            (2,300)          (1,240)            (85)
                                                                    -----------      -----------     -----------

   Standardized measure of discounted future net cash flows        $      2,098     $      1,358    $        186
                                                                    ===========      ===========     ===========



                                       11


   1065




                                                                          For the years ended December 31,
                                                                   ---------------------------------------------
                                                                       2000             1999            1998
                                                                   ------------    -------------    ------------
                                                                                  (in thousands)
                                                                                           
   Oil and Gas Producing Activities:
     Oil and gas sales, net of production costs                    $       (361)   $        (144)   $        (76)
     Net changes in prices and production costs                             775              595            (519)
     Revisions of previous quantity estimates                               350            1,112            (114)
     Accretion of discount                                                  136               19              84
     Changes in production rates, timing and other                         (160)            (410)            (31)
                                                                    -----------     ------------     -----------

     Change in present value of future net revenues                         740            1,172            (656)
                                                                    -----------     ------------     -----------

     Balance, beginning of year                                           1,358              186             842
                                                                    -----------     ------------     -----------

     Balance, end of year                                          $      2,098    $       1,358    $        186
                                                                    ===========     ============     ===========


NOTE 8.         MAJOR CUSTOMERS

   The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:




                                                                     2000            1999             1998
                                                                   --------        --------         --------

                                                                                             
                 Plains Marketing, L.P.                               50%              44%               -
                 Genesis Crude Oil, L.P.                               -                -               49%
                 Western Gas Resources, Inc.                           3%               5%              17%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $25,238 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.


                                       12


   1066


        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $3,636,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.


                                       13


   1067


                        PARKER & PARSLEY 88-B CONV., L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
    RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 84% to $535,228 for 2000 as
compared to $291,390 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 13,209 barrels
of oil, 5,363 barrels of natural gas liquids ("NGLs") and 21,781 mcf of gas were
sold, or 22,202 barrel of oil equivalents ("BOEs"). In 1999, 11,400 barrels of
oil, 5,586 barrels of NGLs and 23,221 mcf of gas were sold, or 20,856 BOEs. Due
to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.12, or 71%, from
$17.17 in 1999 to $29.29 in 2000. The average price received per barrel of NGLs
increased $5.99, or 60%, from $10.03 in 1999 to $16.02 in 2000. The average
price received per mcf of gas increased 69% from $1.70 in 1999 to $2.87 in 2000.
The market price for oil and gas has been extremely volatile in the past decade,
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gain on disposition of assets of $7,186 was recognized during 2000. The gain was
comprised of $5,981 received from the sale of equipment on one well plugged and
abandoned during the current period and $1,205 from equipment credits received
on one fully depleted well.

Total costs and expenses increased in 2000 to $220,151 as compared to $197,819
in 1999, an increase of $22,332, or 11%. The increase was due to increases in
production costs, general and administrative expenses ("G&A") and abandoned
property costs, offset by a decline in depletion.

Production costs were $174,071 in 2000 and $146,805 in 1999, resulting in a
$27,266 increase, or 19%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
84% from $8,615 in 1999 to $15,875 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $13,920 in 2000 and $5,293 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $27,450 in 2000 as compared to $42,399 in 1999, representing a
decrease of $14,949, or 35%. This decrease was primarily due to a 35,962 barrels
of oil increase in proved reserves during 2000 due to higher commodity prices,
offset by an increase in oil production of 1,809 barrels for the period ended
December 31, 2000 compared to the same period in 1999.

Abandoned property costs of $2,755 were incurred during 2000 due to the plugging
and abandonment of one well during


   1068


the current period.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 24% to $291,390 from
$234,942 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 11,400 barrels of oil,
5,586 barrels of NGLs and 23,221 mcf of gas were sold, or 20,856 BOEs. In 1998,
12,653 barrels of oil, 4,957 barrels of NGLs and 21,214 mcf of gas were sold, or
21,146 BOEs.

The average price received per barrel of oil increased $3.93, or 30%, from
$13.24 in 1998 to $17.17 in 1999. The average price received per barrel of NGLs
increased $3.12, or 45%, from $6.91 in 1998 to $10.03 in 1999. The average price
received per mcf of gas increased 9% from $1.56 in 1998 to $1.70 in 1999.

Total costs and expenses decreased in 1999 to $197,819 as compared to $436,801
in 1998, a decrease of $238,982, or 55%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $146,805 in 1999 and $158,704 in 1998, resulting in an
$11,899 decrease, or 7%. The decrease was due to declines in well maintenance
costs, workover costs and ad valorem taxes, offset by an increase in production
taxes due to increased oil and gas revenues.

During this period, G&A increased 21% from $7,091 in 1998 to $8,615 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $5,293 in
1999 and $5,608 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets
to be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $156,111 related to its oil and gas properties during 1998.

Depletion was $42,399 in 1999 compared to $114,895 in 1998, representing a
decrease of $72,496, or 63%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 100,955 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 1,253
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.


   1069


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $191,512 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $246,184, offset by increases in production costs paid
of $27,266, G&A expenses paid of $7,260 abandoned property costs paid of $2,755
and working capital of $17,391. The increase in oil and gas receipts resulted
from the increase in commodity prices during 2000 which contributed an
additional $200,923 to oil and gas receipts and an increase of $45,261 resulting
from the increase in production during 2000. The increase in production costs
was primarily due to increased production taxes associated with higher oil and
gas prices and additional well maintenance and workover costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were
related to equipment upgrades on active properties.

Proceeds from disposition of assets of $7,186 were recognized during 2000. The
proceeds were comprised of $5,981 received from the sale of equipment on one
well plugged and abandoned during the current period and $1,205 from equipment
credits received on one active well. Proceeds of $4,369 during 1999 were
primarily related to equipment dispositions on one oil and gas well that is
temporarily abandoned.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $319,176, of which $3,192 was
distributed to the managing general partner and $315,984 to the limited
partners. In 1999, cash distributions to the partners were $106,208, of which
$1,062 was distributed to the managing general partner and $105,146 to the
limited partners.




   1070




                        PARKER & PARSLEY 88-B CONV., L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  117,117   $  535,228   $  291,390   $  234,942   $  329,125   $  427,360
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  156,111   $  222,425   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   69,710   $  327,306   $   96,268   $ (198,712)  $ (140,168)  $  161,450
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      697   $    3,273   $      963   $   (1,987)  $   (1,402)  $    1,615
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   69,013   $  324,033   $   95,305   $ (196,725)  $ (138,766)  $  159,835
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    18.98   $    89.12   $    26.21   $   (54.10)  $   (38.16)  $    43.96
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    18.22   $    86.90   $    28.92   $    24.02   $    50.67   $    54.12
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  536,296   $  538,385   $  532,243   $  540,608   $  832,047   $1,155,784
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1071
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 88-B, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
88-B, L.P., and supplements the proxy statement/prospectus dated      , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 88-B, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   1072

                           PARKER & PARSLEY 88-B, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $   8,954

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $  10,116

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   2,844
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  321.02

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.33 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  138.32

        --        as of December 31, 2000  (c)                                                 $  145.00

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  299.32

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  311.59

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     145
(c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.




                                      -2-
   1073



                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-19659-02


                           PARKER & PARSLEY 88-B, L.P.
             (Exact name of Registrant as specified in its charter)

                        Delaware                              75-2240121
            ---------------------------------           ---------------------
             (State or other jurisdiction of              (I.R.S. Employer
             incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
             (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.


                                Yes [X]   No [ ]


   1074



                           PARKER & PARSLEY 88-B, L.P.

                                TABLE OF CONTENTS




                                                                        Page

                                                                      
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................    9

            Signatures...............................................   10



                                        2

   1075



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                      March 31,     December 31,
                                                        2001            2000
                                                    ------------    -----------
                                                    (Unaudited)
                  ASSETS

                                                              
Current assets:
  Cash                                               $  139,057      $  144,763
  Accounts receivable - oil and gas sales               159,140         198,467
                                                     ----------      ----------
        Total current assets                            298,197         343,230
                                                     ----------      ----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                6,955,501       6,954,545
Accumulated depletion                                (5,985,549)     (5,969,972)
                                                     ----------      ----------
        Net oil and gas properties                      969,952         984,573
                                                     ----------      ----------
                                                     $1,268,149      $1,327,803
                                                     ==========      ==========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $   17,198      $   16,350

Partners' capital:
  Managing general partner                               12,478          13,083
  Limited partners (8,954 interests)                  1,238,473       1,298,370
                                                     ----------      ----------
                                                      1,250,951       1,311,453
                                                     ----------      ----------
                                                     $1,268,149      $1,327,803
                                                     ==========      ==========



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   1076



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                       Three months ended
                                                            March 31,
                                                    -------------------------
                                                       2001           2000
                                                    ----------     ----------

                                                             
Revenues:
   Oil and gas                                       $ 326,397      $ 288,612
   Interest                                              2,721          2,092
                                                     ---------      ---------
                                                       329,118        290,704
                                                     ---------      ---------
Costs and expenses:
   Oil and gas production                              104,442         90,211
   General and administrative                            8,160          8,938
   Depletion                                            15,577         19,708
                                                     ---------      ---------
                                                       128,179        118,857
                                                     ---------      ---------
Net income                                           $ 200,939      $ 171,847
                                                     =========      =========
Allocation of net income
   Managing general partner                          $   2,009      $   1,718
                                                     =========      =========
   Limited partners                                  $ 198,930      $ 170,129
                                                     =========      =========
Net income per limited partnership interest          $   22.22      $   19.00
                                                     =========      =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   1077



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                  Managing
                                  general          Limited
                                  partner          partners            Total
                                -----------       -----------       -----------


                                                           
Balance at January 1, 2001      $    13,083       $ 1,298,370       $ 1,311,453

    Distributions                    (2,614)         (258,827)         (261,441)

    Net income                        2,009           198,930           200,939
                                -----------       -----------       -----------

Balance at March 31, 2001       $    12,478       $ 1,238,473       $ 1,250,951
                                ===========       ===========       ===========







         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   1078



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                        Three months ended
                                                             March 31,
                                                     -------------------------
                                                        2001           2000
                                                     ----------     ----------

                                                              
Cash flows from operating activities:
  Net income                                          $ 200,939      $ 171,847
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         15,577         19,708
  Changes in assets and liabilities:
       Accounts receivable                               39,327            811
       Accounts payable                                     848          3,189
                                                      ---------      ---------
         Net cash provided by operating activities      256,691        195,555
                                                      ---------      ---------
Cash flows from investing activities:
  Additions to oil and gas properties                    (1,480)        (1,883)
  Proceeds from disposition of assets                       524             --
                                                      ---------      ---------
         Net cash used in investing activities             (956)        (1,883)
                                                      ---------      ---------
Cash flows used in financing activities:
  Cash distributions to partners                       (261,441)      (164,763)
                                                      ---------      ---------
Net increase (decrease) in cash                          (5,706)        28,909
Cash at beginning of period                             144,763        129,430
                                                      ---------      ---------
Cash at end of period                                 $ 139,057      $ 158,339
                                                      =========      =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   1079



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley 88-B, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 13% to $326,397 for the three
months ended March 31, 2001 as compared to $288,612 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 6,753
barrels of oil, 2,315 barrels of natural gas liquids ("NGLs") and 8,631 mcf of
gas were sold, or 10,507 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 8,236 barrels of oil, 3,267 barrels of NGLs and


                                        7

   1080



14,019 mcf of gas were sold, or 13,840 BOEs. Of the decrease, 2,758 BOEs are
attributable to three wells reaching payout pursuant to the terms of the farmout
agreements which reduced the Partnership's net revenue interest in the wells.

The average price received per barrel of oil increased $3.39, or 13%, from
$26.41 for the three months ended March 31, 2000 to $29.80 for the same period
in 2001. The average price received per barrel of NGLs increased $5.63, or 39%,
from $14.34 for the three months ended March 31, 2000 to $19.97 for the same
period in 2001. The average price received per mcf of gas increased 428% from
$1.73 during the three months ended March 31, 2000 to $9.14 for the same period
in 2001. The market price for oil and gas has been extremely volatile in the
past decade, and management expects a certain amount of volatility to continue
in the foreseeable future. The Partnership may therefore sell its future oil and
gas production at average prices lower or higher than that received during the
three months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $128,179 for the three months ended March
31, 2001 as compared to $118,857 for the same period in 2000, an increase of
$9,322, or 8%. The increase was primarily due to an increase in production
costs, offset by decreases in depletion and general and administrative expenses
("G&A").

Production costs were $104,442 for the three months ended March 31, 2001 and
$90,211 for the same period in 2000, resulting in a $14,231 increase, or 16%.
The increase in production costs was primarily due to higher production taxes
associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production, offset by a decline in
lease operating and production taxes attributable to the wells that reached
payout pursuant to the terms of the farmout agreements as noted above.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
decreased 9% from $8,938 for the three months ended March 31, 2000 to $8,160 for
the same period in 2001.

Depletion was $15,577 for the three months ended March 31, 2001 as compared to
$19,708 for the same period in 2000, a decrease of $4,131, or 21%. This decrease
was primarily due to a decrease in oil production of 1,483 barrels for the three
months ended March 31, 2001 compared to the same period in 2000 and positive
revisions to proved reserves during the three months ended March 31, 2001 as a
result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $61,136 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $38,414 in oil and gas sales receipts
and reductions of $778 in G&A expenses and $36,175 in working capital, offset by
an increase in production costs of $14,231. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $150,881 to oil and gas receipts, offset by $112,467 resulting from

                                        8

   1081



the decline in production during 2001 as compared to the same period in 2000.
The increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 were for equipment upgrades on active oil and gas
properties.

Proceeds from disposition of assets of $524 recognized during the three months
ended March 31, 2001 were due to equipment credits received on active
properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $261,441, of which $2,614 was distributed to the managing general partner
and $258,827 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $164,763, of which $1,648 was
distributed to the managing general partner and $163,115 to the limited
partners.

Proposal to acquire partnerships

On April 18, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement with the SEC proposing an agreement and plan of
merger among Pioneer, Pioneer Natural Resources USA, Inc. ("Pioneer USA"), a
wholly-owned subsidiary of Pioneer, and the limited partners of 46 Parker &
Parsley limited partnerships. Pioneer USA is the sole or managing general
partner of the partnerships. The preliminary proxy statement is non-binding and
is subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partners in each partnership and the resolution of SEC review comments. If
approved, Pioneer anticipates closing the mergers during the third quarter of
2001.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)      Exhibits - none

(b)      Reports on Form 8-K - none.



                                        9

   1082


                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                          PARKER & PARSLEY 88-B, L.P.

                                 By:      Pioneer Natural Resources USA, Inc.
                                           Managing General Partner



Dated:  May 9, 2001              By:      /s/ Rich Dealy
                                          ----------------------------------
                                          Rich Dealy, Vice President
                                            and Chief Accounting Officer


                                       10



   1083
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-19659-02


                           PARKER & PARSLEY 88-B, L.P.
             (Exact name of Registrant as specified in its charter)

                   DELAWARE                                75-2240121
       -------------------------------                ----------------------
       (State or other jurisdiction of                  (I.R.S. Employer
        incorporation or organization)                Identification Number)



                                                                                
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                     75039
             (Address of principal executive offices)                              (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
           Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES /X/ NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. /X/

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$8,860,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 8,954.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.




   1084

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 88-B, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 8,954 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 50% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial



                                       2
   1085

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located in
the Spraberry Trend area of West Texas were acquired by the Partnership,
resulting in the Partnership's participation in the drilling of 43 oil and gas
wells. Two wells have been plugged and abandoned. At December 31, 2000, 41 wells
were producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.




                                       3
   1086


                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
           DISTRIBUTIONS

At March 8, 2001, the Partnership had 8,954 outstanding limited partnership
interests held of record by 690 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $778,145 and $258,933, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                    2000            1999          1998            1997           1996
                                  ----------     ----------     ----------     ----------     ----------
                                                                               
Operating results:
------------------
  Oil and gas sales               $1,318,092     $  717,449     $  578,573     $  810,500     $1,052,408
                                  ==========     ==========     ==========     ==========     ==========

  Impairment of oil and gas
    properties                    $      -       $      -       $  383,951     $  547,793     $      -
                                  ==========     ==========     ==========     ==========     ==========

  Net income (loss)               $  805,539     $  236,642     $ (488,631)    $ (344,997)    $  397,674
                                  ==========     ==========     ==========     ==========     ==========

  Allocation of net income
    (loss):
    Managing general partner      $    8,055     $    2,366     $   (4,887)    $   (3,450)    $    3,977
                                  ==========     ==========     ==========     ==========     ==========

    Limited partners              $  797,484     $  234,276     $ (483,744)    $ (341,547)    $  393,697
                                  ==========     ==========     ==========     ==========     ==========

  Limited partners' net
    income (loss) per limited
    partnership interest          $    89.06     $    26.16     $   (54.03)    $   (38.14)    $    43.97
                                  ==========     ==========     ==========     ==========     ==========


  Limited partners' cash
    distributions per limited
    partnership interest          $    86.90     $    28.92     $    24.02     $    50.67     $    54.14
                                  ==========     ==========     ==========     ==========     ==========

At year end:
------------
  Identifiable assets             $1,327,803     $1,313,164     $1,334,302     $2,051,284     $2,848,468
                                  ==========     ==========     ==========     ==========     ==========





                                       4
   1087


ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
           RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 84% to $1,318,092 for 2000 as
compared to $717,449 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 32,524 barrels
of oil, 13,205 barrels of natural gas liquids ("NGLs") and 53,620 mcf of gas
were sold, or 54,666 barrel of oil equivalents ("BOEs"). In 1999, 28,078 barrels
of oil, 13,752 NGLs and 57,190 mcf of gas were sold, or 51,362 BOEs. Due to the
decline characteristics of the Partnership's oil and gas properties, management
expects a certain amount of decline in production in the future until the
Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.12, or 71%, from
$17.17 in 1999 to $29.29 in 2000. The average price received per barrel of NGLs
increased $5.99, or 60%, from $10.03 in 1999 to $16.02 in 2000. The average
price received per mcf of gas increased 69% from $1.70 in 1999 to $2.87 in 2000.
The market price for oil and gas has been extremely volatile in the past decade
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gain on disposition of assets of $17,697 was recognized during 2000. The gain
was comprised of $14,729 received from the sale of equipment on one well plugged
and abandoned during the current period and $2,968 from equipment credits
received on one fully depleted well.

Total costs and expenses increased in 2000 to $542,703 as compared to $487,566
in 1999, an increase of $55,137, or 11%. The increase was due to increases in
production costs, general and administrative expenses ("G&A") and abandoned
property costs, offset by a decline in depletion.

Production costs were $428,633 in 2000 and $361,482 in 1999, resulting in an
increase of $67,151, or 19%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
and workover costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
83% from $21,650 in 1999 to $39,725 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $34,281 in 2000 and $13,039 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   1088


Depletion was $67,561 in 2000 as compared to $104,434 in 1999, representing a
decrease of $36,873, or 35%. This decrease was primarily due to a 88,489 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices, offset by an increase in oil production of 4,446 barrels for the period
ended December 31, 2000 compared to the same period in 1999.

Abandoned property costs of $6,784 incurred in 2000 were related to the plugging
and abandonment of one well during the current year.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 24% to $717,449 from
$578,573 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 28,078 barrels of oil,
13,752 barrels of NGLs and 57,190 mcf of gas were sold, or 51,362 BOEs. In 1998,
31,155 barrels of oil, 12,210 NGLs and 52,254 mcf of gas were sold, or 52,074
BOEs.

The average price received per barrel of oil increased $3.93, or 30%, from
$13.24 in 1998 to $17.17 in 1999. The average price received per barrel of NGLs
increased $3.12, or 45%, from $6.91 in 1998 to $10.03 in 1999. The average price
received per mcf of gas increased 9% from $1.56 in 1998 to $1.70 in 1999.

Total costs and expenses decreased in 1999 to $487,566 as compared to $1,075,163
in 1998, a decrease of $587,597, or 55%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $361,482 in 1999 and $390,835 in 1998, resulting in a
$29,353 decrease, or 8%. The decrease was primarily due to declines in well
maintenance costs, workover costs and ad valorem taxes, offset by an increase in
production taxes due to increased oil and gas revenues.

During this period, G&A increased 25% from $17,315 in 1998 to $21,650 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $13,039 in
1999 and $13,810 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $383,951 related to its oil and gas properties during 1998.

Depletion was $104,434 in 1999 compared to $283,062 in 1998. This represented a
decrease of $178,628, or 63%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 248,642 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 3,077
barrels for the period ended



                                       6
   1089

December 31, 1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $512,129 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $606,337, offset by increases in production costs paid
of $67,151, G&A expenses paid of $18,075, abandoned property costs paid of
$6,784 and working capital of $2,198. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2000 which contributed an
additional $495,153 to oil and gas receipts and an increase of $111,184
resulting from the increase in production during 2000. The increase in
production costs was primarily due to increased production taxes associated with
higher oil and gas prices and additional well maintenance and workover costs
incurred to stimulate well production. The increase in G&A was primarily due to
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues.


Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to the
upgrades of oil and gas equipment on active properties.

Proceeds from disposition of assets of $17,697 were recognized during 2000. The
proceeds were comprised of $14,729 received from the sale of equipment on one
well plugged and abandoned during the current period and $2,968 from equipment
credits received on active wells. Proceeds of $10,758 recognized during 1999
were related to equipment disposals on one temporarily abandoned oil and gas
well.

Net Cash Used in Financing Activities



                                       7
   1090


In 2000, cash distributions to the partners were $786,005, of which $7,860 was
distributed to the managing general partner and $778,145 to the limited
partners. In 1999, cash distributions to the partners were $261,548, of which
$2,615 was distributed to the managing general partner and $258,933 to the
limited partners.



                                       8
   1091


ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----
                                                                                      
Financial Statements of Parker & Parsley 88-B, L.P.:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15





                                       9
   1092



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 88-B, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 88-B, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 88-B, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                          Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       10
   1093

                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                      2000             1999
                                                   -----------      -----------

                                                              
                  ASSETS
                  ------

Current assets:
  Cash                                             $   144,763      $   129,430
  Accounts receivable - oil and gas sales              198,467          138,030
                                                   -----------      -----------

       Total current assets                            343,230          267,460
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               6,954,545        7,129,071
Accumulated depletion                               (5,969,972)      (6,083,367)
                                                   -----------      -----------

       Net oil and gas properties                      984,573        1,045,704
                                                   -----------      -----------

                                                   $ 1,327,803      $ 1,313,164
                                                   ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                     $    16,350      $    21,245

Partners' capital:
  Managing general partner                              13,083           12,888
  Limited partners (8,954 interests)                 1,298,370        1,279,031
                                                   -----------      -----------

                                                     1,311,453        1,291,919
                                                   -----------      -----------
                                                   $ 1,327,803      $ 1,313,164
                                                   ===========      ===========




   The accompanying notes are an integral part of these financial statements.



                                       11
   1094



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                            2000           1999           1998
                                                         ----------     ----------     -----------

                                                                              
Revenues:
  Oil and gas                                            $1,318,092     $  717,449     $   578,573
  Interest                                                   12,453          6,759           7,803
  Other                                                         -              -               156
  Gain on disposition of assets                              17,697            -               -
                                                         ----------     ----------     -----------

                                                          1,348,242        724,208         586,532
                                                         ----------     ----------     -----------

Costs and expenses:
  Oil and gas production                                    428,633        361,482         390,835
  General and administrative                                 39,725         21,650          17,315
  Impairment of oil and gas properties                          -              -           383,951
  Depletion                                                  67,561        104,434         283,062
  Abandoned property                                          6,784            -               -
                                                         ----------     ----------     -----------

                                                            542,703        487,566       1,075,163
                                                         ----------     ----------     -----------

Net income (loss)                                        $  805,539     $  236,642     $  (488,631)
                                                         ==========     ==========     ===========

Allocation of net income (loss):
  Managing general partner                               $    8,055     $    2,366     $    (4,887)
                                                         ==========     ==========     ===========

  Limited partners                                       $  797,484     $  234,276     $  (483,744)
                                                         ==========     ==========     ===========

Net income (loss) per limited partnership interest       $    89.06     $    26.16     $    (54.03)
                                                         ==========     ==========     ===========




   The accompanying notes are an integral part of these financial statements.



                                       12
   1095



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                           Managing
                                            general       Limited
                                            partner       partners           Total
                                           ---------     -----------      -----------

                                                                 
Partners' capital at January 1, 1998       $ 20,196      $ 2,002,489      $ 2,022,685

   Distributions                             (2,172)        (215,057)        (217,229)

   Net loss                                  (4,887)        (483,744)        (488,631)
                                           --------      -----------      -----------

Partners' capital at December 31, 1998       13,137        1,303,688        1,316,825

   Distributions                             (2,615)        (258,933)        (261,548)

   Net income                                 2,366          234,276          236,642
                                           --------      -----------      -----------

Partners' capital at December 31, 1999       12,888        1,279,031        1,291,919

   Distributions                             (7,860)        (778,145)        (786,005)

   Net income                                 8,055          797,484          805,539
                                           --------      -----------      -----------

Partners' capital at December 31, 2000     $ 13,083      $ 1,298,370      $ 1,311,453
                                           ========      ===========      ===========






   The accompanying notes are an integral part of these financial statements.



                                       13
   1096



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                       2000           1999           1998
                                                     ---------      ---------      ---------

                                                                          
Cash flows from operating activities:
   Net income (loss)                                 $ 805,539      $ 236,642      $(488,631)
   Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
       Impairment of oil and gas properties                -              -          383,951
       Depletion                                        67,561        104,434        283,062
       Other                                               -              -             (156)
       Gain on disposition of assets                   (17,697)           -              -
   Changes in assets and liabilities:
     Accounts receivable                               (60,437)       (66,902)        26,411
     Accounts payable                                   (4,895)         3,768        (11,122)
                                                     ---------      ---------      ---------

     Net cash provided by operating activities         790,071        277,942        193,515
                                                     ---------      ---------      ---------

Cash flows from investing activities:
   Additions to oil and gas properties                  (6,430)        (8,363)       (15,067)
   Proceeds from asset dispositions                     17,697         10,758            156
                                                     ---------      ---------      ---------

     Net cash provided by (used in)
       investing activities                             11,267          2,395        (14,911)
                                                     ---------      ---------      ---------

Cash flows from financing activities:
   Cash distributions to partners                     (786,005)      (261,548)      (217,229)
                                                     ---------      ---------      ---------

Net increase (decrease) in cash                         15,333         18,789        (38,625)
Cash at beginning of year                              129,430        110,641        149,266
                                                     ---------      ---------      ---------

Cash at end of year                                  $ 144,763      $ 129,430      $ 110,641
                                                     =========      =========      =========




   The accompanying notes are an integral part of these financial statements.



                                       14
   1097



                           PARKER & PARSLEY 88-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 88-B, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the



                                       15
   1098

respective partners.

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation been consistent over
the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $383,951 related to
its proved oil and gas properties during 1998.




                                       16
   1099

NOTE 4.    INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $77,883 greater than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                         2000           1999          1998
                                                       ---------      --------     ---------

                                                                          
Net income (loss) per statements of operations         $ 805,539      $236,642     $(488,631)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                            58,194        94,173       274,063
Impairment of oil and gas properties for financial
  reporting purposes                                         -             -         383,951
Other                                                     (2,494)        8,701         1,161
                                                       ---------      --------     ---------

      Net income per Federal income tax
        returns                                        $ 861,239      $339,516     $ 170,544
                                                       =========      ========     =========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                               2000              1999              1998
                                             --------          --------          --------

                                                                        
    Development costs                        $  6,430          $  8,363          $ 15,067
                                             ========          ========          ========


      Capitalized oil and gas properties consist of the following:



                                                                 2000               1999
                                                              -----------       -----------
                                                                          
      Proved properties:
        Property acquisition costs                            $   426,682       $   439,249
        Completed wells and equipment                           6,527,863         6,689,822
                                                              -----------       -----------

                                                                6,954,545         7,129,071
      Accumulated depletion                                    (5,969,972)       (6,083,367)
                                                              -----------       -----------

          Net oil and gas properties                          $   984,573       $ 1,045,704
                                                              ===========       ===========



                                       17
   1100


NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                  2000         1999         1998
                                                --------     --------     --------
                                                                 
Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                 $159,314     $157,042     $150,985

Reimbursement of general and administrative
  expenses                                      $ 34,281     $ 13,039     $ 13,810


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 88-B Conv., L.P. and the Partnership (the "Partnerships") are
parties to the Program agreement.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                                   Pioneer USA (1)    Partnerships (2)
                                                                   ---------------    ----------------

                                                                                
    Revenues:
      Proceeds from disposition of depreciable properties               9.09091%         90.90909%
      All other revenues                                              24.242425%        75.757575%
    Costs and expenses:
      Lease acquisition costs, drilling and completion
        costs and all other costs                                       9.09091%         90.90909%
      Operating costs, direct costs and general and
        administrative expenses                                       24.242425%        75.757575%


     (1)  Excludes Pioneer USA's 1% general partner ownership which is allocated
          at the Partnership level and 94 limited partner interests owned by
          Pioneer USA.

     (2)  The allocation between the Partnership and Parker & Parsley 88-B
          Conv., L.P. is 71.119936% and 28.880064%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared Williamson Petroleum
Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                       18
   1101



                                                              Oil and NGLs          Gas
                                                                 (bbls)            (mcf)
                                                              ------------      ----------

                                                                          
    Net proved reserves at January 1, 1998                       528,956           612,323
    Revisions                                                   (215,651)         (183,598)
    Production                                                   (43,365)          (52,254)
                                                              ----------        ----------

    Net proved reserves at December 31, 1998                     269,940           376,471
    Revisions                                                    375,777           553,985
    Production                                                   (41,830)          (57,190)
                                                              ----------        ----------
    Net proved reserves at December 31, 1999                     603,887           873,266
    Revisions                                                    114,704            59,721
    Production                                                   (45,729)          (53,620)
                                                              ----------        ----------

    Net proved reserves at December 31, 2000                     672,862           879,367
                                                              ==========        ==========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.59 per barrel of NGLs and $7.85 per mcf of gas,
discounted at 10% was approximately $5,167,000 and undiscounted was $10,831,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

      The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

      Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                 For the years ended December 31,
                                                               -----------------------------------
                                                                 2000          1999         1998
                                                               --------      --------      -------
                                                                          (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                          $ 22,071      $ 15,072      $ 2,957
  Future production costs                                       (11,240)       (8,674)      (2,289)
                                                               --------      --------      -------

                                                                 10,831         6,398          668
  10% annual discount factor                                     (5,664)       (3,054)        (210)
                                                               --------      --------      -------

  Standardized measure of discounted future net cash flows     $  5,167      $  3,344      $   458
                                                               ========      ========      =======



                                       19
   1102



                                                     For the years ended December 31,
                                                     ---------------------------------
                                                      2000         1999         1998
                                                     -------      -------      -------
                                                              (in thousands)
                                                                      
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs         $  (889)     $  (356)     $  (188)
  Net changes in prices and production costs           1,910        1,466       (1,276)
  Revisions of previous quantity estimates               862        2,739         (280)
  Accretion of discount                                  334           46          207
  Changes in production rates, timing and other         (394)      (1,009)         (77)
                                                     -------      -------      -------

  Change in present value of future net revenues       1,823        2,886       (1,614)
                                                     -------      -------      -------

  Balance, beginning of year                           3,344          458        2,072
                                                     -------      -------      -------

  Balance, end of year                               $ 5,167      $ 3,344      $   458
                                                     =======      =======      =======


NOTE 8.    MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
           Plains Marketing, L.P.                     50%            44%            -
           Genesis Crude Oil, L.P.                     -              -            49%
           Western Gas Resources, Inc.                 3%             5%           17%


      At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $62,153 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the limited partnership agreement, the managing general partner pays
      1% of the Partnership's acquisition, drilling and completion costs and 1%
      of its operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.



                                       20
   1103

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of $8,954,000.
      Pioneer USA is required to contribute amounts equal to 1% of initial
      Partnership capital less commission and offering expenses allocated to the
      limited partners and to contribute amounts necessary to pay costs and
      expenses allocated to it under the Partnership agreement to the extent its
      share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
           AND FINANCIAL DISCLOSURE

None.





                                       21
   1104



                                    PART III

ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                             
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       22
   1105



      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       23
   1106



ITEM 11.    EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 25% of its operating and general
and administrative expenses. In return, Pioneer USA is allocated approximately
25% of the Program's revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 94 limited partner interests at January 1, 2001.

(b)   Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                       24
   1107





                                                       2000          1999           1998
                                                     --------      ---------      --------
                                                                         
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreement                   $159,314      $ 157,042      $150,985

    Reimbursement of general and administrative
      expenses                                       $ 34,281      $  13,039      $ 13,810


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.



                                       25
   1108



                                     PART IV

ITEM 14.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                  Independent Auditors' Report

                  Balance sheets as of December 31, 2000 and 1999

                  Statements of operations for the years ended December 31,
                    2000, 1999 and 1998

                  Statements of partners' capital for the years ended December
                    31, 2000, 1999 and 1998

                  Statements of cash flows for the years ended December 31,
                    2000, 1999 and 1998

                  Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       26
   1109



                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 88-B, L.P.

Dated: March 29, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                --------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 29, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 29, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 29, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 29, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 29, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 29, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       27
   1110



                           PARKER & PARSLEY 88-B, L.P.

                                INDEX TO EXHIBITS



      The following documents are incorporated by reference in response to Item
14(c):



    Exhibit No.                             Description                           Page
    -----------                             -----------                           ----

                                                                            
       3(a)                Amended and Restated Certificate and                     -
                           Agreement of Limited Partnership of
                           Parker & Parsley 88-B, L.P. incorporated
                           by reference to Exhibit A of Amendment
                           No. 1 of the Partnership's Registration
                           Statement on Form S-1 (Registration No.
                           33-19659)

       4(b)                Form of Subscription Agreement and                       -
                           Power of Attorney incorporated by reference to
                           Exhibit D of the Partnership's Registration Statement
                           on Form S-1 (Registration No. 33-19659) (hereinafter
                           called the Partnership's Registration Statement)

       4(c)                Specimen Certificate of Limited Partnership              -
                           Interest incorporated by reference to Exhibit
                           D of the Partnership's Registration Statement

      10(b)                Exploration and Development Program                      -
                           Agreement incorporated by reference to
                           Exhibit C of the Partnership's Registration
                           Statement






                                       28
   1111



                           PARKER & PARSLEY 88-B, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  288,612   $1,318,092   $  717,449   $  578,573   $  810,500   $1,052,408
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  383,951   $  547,793   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  171,847   $  805,539   $  236,642   $ (488,631)  $ (344,997)  $  397,674
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
         partner                   $          $    1,718   $    8,055   $    2,366   $   (4,887)  $   (3,450)  $    3,977
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  170,129   $  797,484   $  234,276   $ (483,744)  $ (341,547)  $  393,697
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    19.00   $    89.06   $    26.16   $   (54.03)  $   (38.14)  $    43.97
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    18.22   $    86.90   $    28.92   $    24.02   $    50.67   $    54.14
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,323,437   $1,327,803   $1,313,164   $1,334,302   $2,051,284   $2,848,468
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1112

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 88-C CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED          , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS          , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
88-C Conv., L.P., and supplements the proxy statement/prospectus dated         ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 88-C Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1113


                        PARKER & PARSLEY 88-C CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                      
Aggregate Initial Investment by the Limited Partners(a)                                                  $      3,411

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                              $      3,591

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)    $        938

Merger Value per $1,000 Limited Partner Investment(b), (c)                                               $     275.69

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                            3.31 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                      $     137.58

      --    as of December 31, 2000(c)                                                                   $     142.82

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                        $     256.95

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                          $     267.63

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)            $        149



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as any
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   1114

                        PARKER & PARSLEY 88-C CONV,. L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001

   1115



                        PARKER & PARSLEY 88-C CONV,. L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS





                                                      March 31,     December 31,
                                                        2001            2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS

                                                              
Current assets:
  Cash                                              $    48,795     $    51,156
  Accounts receivable - oil and gas sales                56,886          66,963
                                                    -----------     -----------
        Total current assets                            105,681         118,119
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                2,458,423       2,458,118
Accumulated depletion                                (2,084,100)     (2,078,258)
                                                    -----------     -----------
        Net oil and gas properties                      374,323         379,860
                                                    -----------     -----------
                                                    $   480,004     $   497,979
                                                    ===========     ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $     6,003     $     5,927

Partners' capital:
  Managing general partner                                4,725           4,905
  Limited partners (3,411 interests)                    469,276         487,147
                                                    -----------     -----------
                                                        474,001         492,052
                                                    -----------     -----------
                                                    $   480,004     $   497,979
                                                    ===========     ===========



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        2
   1116


                        PARKER & PARSLEY 88-C CONV,. L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                         Three months ended
                                                              March 31,
                                                     --------------------------
                                                        2001            2000
                                                     ----------      ----------
                                                               
Revenues:
  Oil and gas                                        $  112,186      $   95,029
  Interest                                                  945             756
                                                     ----------      ----------
                                                        113,131          95,785
                                                     ----------      ----------
Costs and expenses:
  Oil and gas production                                 35,748          34,061
  General and administrative                              3,766           2,851
  Depletion                                               5,842           6,967
                                                     ----------      ----------
                                                         45,356          43,879
                                                     ----------      ----------
Net income                                           $   67,775      $   51,906
                                                     ==========      ==========
Allocation of net income:
  Managing general partner                           $      678      $      519
                                                     ==========      ==========
  Limited partners                                   $   67,097      $   51,387
                                                     ==========      ==========
Net income per limited partnership interest          $    19.67      $    15.07
                                                     ==========      ==========




         The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3
   1117



                        PARKER & PARSLEY 88-C CONV,. L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                      Managing
                                      general       Limited
                                      partner       partners        Total
                                     ---------     ----------     ----------
                                                         
Balance at January 1, 2001           $   4,905     $  487,147     $  492,052

    Distributions                         (858)       (84,968)       (85,826)

    Net income                             678         67,097         67,775
                                     ---------     ----------     ----------

Balance at March 31, 2001            $   4,725     $  469,276     $  474,001
                                     =========     ==========     ==========



         The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.


                                        4
   1118


                        PARKER & PARSLEY 88-C CONV,. L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                           Three months ended
                                                                March 31,
                                                        -----------------------
                                                           2001         2000
                                                        ---------     ---------
                                                                
Cash flows from operating activities:
  Net income                                            $  67,775     $  51,906
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            5,842         6,967
  Changes in assets and liabilities:
       Accounts receivable                                 10,077         1,855
       Accounts payable                                        76           230
                                                        ---------     ---------
           Net cash provided by operating activities       83,770        60,958
                                                        ---------     ---------
Cash flows from investing activities:
  Additions to oil and gas properties                        (473)         (616)
  Proceeds from disposition of assets                         168            --
                                                        ---------     ---------
           Net cash used in investing activities             (305)         (616)
                                                        ---------     ---------
Cash flows used in financing activities:
  Cash distributions to partners                          (85,826)      (56,445)
                                                        ---------     ---------
Net increase (decrease) in cash                            (2,361)        3,897
Cash at beginning of period                                51,156        56,353
                                                        ---------     ---------
Cash at end of period                                   $  48,795     $  60,250
                                                        =========     =========



       The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.


                                        5
   1119


                        PARKER & PARSLEY 88-C CONV,. L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1. Organization and nature of operations

Parker & Parsley 88-C Conv., L.P. (the "Partnership") was organized in 1988 as a
general partnership under the laws of the State of Texas and was converted to a
Delaware limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2. Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 18% to $112,186 for the three
months ended March 31, 2001 as compared to $95,029 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 2,158
barrels of oil, 953 barrels of natural gas liquids ("NGLs") and 3,530 mcf of gas
were sold, or 3,699 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 2,693 barrels of oil, 1,122 barrels of NGLs and 4,769 mcf
of gas were sold, or 4,610 BOEs. Of the decrease, 881 BOEs are attributable to
three wells reaching payout pursuant to the terms of the farmout agreements
which reduced the Partnership's net revenue interest in the wells.


                                        6
   1120


The average price received per barrel of oil increased $3.74, or 14%, from
$26.37 for the three months ended March 31, 2000 to $30.11 for the same period
in 2001. The average price received per barrel of NGLs increased $5.19, or 36%,
from $14.26 for the three months ended March 31, 2000 to $19.45 for the same
period in 2001. The average price received per mcf of gas increased 378% from
$1.70 during the three months ended March 31, 2000 to $8.12 for the same period
in 2001. The market price for oil and gas has been extremely volatile in the
past decade, and management expects a certain amount of volatility to continue
in the foreseeable future. The Partnership may therefore sell its future oil and
gas production at average prices lower or higher than that received during the
three months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $45,356 for the three months ended March
31, 2001 as compared to $43,879 for the same period in 2000, an increase of
$1,477, or 3%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $35,748 for the three months ended March 31, 2001 and
$34,061 for the same period in 2000 resulting in a $1,687 increase, or 5%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices and additional workover and well maintenance costs incurred to
stimulate well production, offset by a decline in lease operating and production
taxes attributable to the wells that reached payout pursuant to the terms of the
farmout agreements as noted above.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 32% from $2,851 for the three months ended March 31, 2000 to $3,766
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $5,842 for the three months ended March 31, 2001 compared to
$6,967 for the same period in 2000, a decrease of $1,125, or 16%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices and a decline
in oil production of 535 barrels for the three months ended March 31, 2001 as
compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $22,812 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $17,346 and a
reduction of $8,068 in working capital, offset by increases in production costs
of $1,687 and G&A expenses of $915. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $46,804 to oil and gas receipts, offset by $29,458 resulting from the


                                        7
   1121

decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional workover costs incurred
to stimulate well production, offset by a decline in lease operating and
production taxes attributable to the wells that reached payout pursuant to the
terms of the farmout agreements. The increase in G&A was primarily due to an
increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from disposition of assets of $168 recognized during the three months
ended March 31, 2001 were due to equipment credits received on one active well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $85,826, of which $858 was distributed to the managing general partner and
$84,968 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $56,445, of which $564 was distributed to the
managing general partner and $55,881 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.


                                        8
   1122


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   1123



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 88-C Conv., L.P.
 (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 88-C Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 88-C Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                               Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   1124


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                            2000                1999
                                                         -----------        -----------
                                                                      
              ASSETS
              ------

Current assets:
  Cash                                                   $    51,156        $    56,353
  Accounts receivable - oil and gas sales                     66,963             40,622
                                                         -----------        -----------

         Total current assets                                118,119             96,975
                                                         -----------        -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                     2,458,118          2,513,824
Accumulated depletion                                     (2,078,258)        (2,110,906)
                                                         -----------        -----------

         Net oil and gas properties                          379,860            402,918
                                                         -----------        -----------

                                                         $   497,979        $   499,893
                                                         ===========        ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                           $     5,927        $     8,955

Partners' capital:
  Managing general partner                                     4,905              4,894
  Limited partners (3,411 interests)                         487,147            486,044
                                                         -----------        -----------

                                                             492,052            490,938
                                                         -----------        -----------

                                                         $   497,979        $   499,893
                                                         ===========        ===========






   The accompanying notes are an integral part of these financial statements.


                                       3
   1125


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                               2000          1999          1998
                                                            ---------     ---------     ---------
                                                                                 

Revenues:
   Oil and gas                                              $ 443,642     $ 246,242       200,460
   Interest                                                     4,268         2,112         2,970
   Gain on disposition of assets                                5,650             -         2,175
                                                            ---------     ---------     ---------

                                                              453,560       248,354       205,605
                                                            ---------     ---------     ---------

Costs and expenses:
   Oil and gas production                                     151,650       131,165       142,438
   General and administrative                                  13,129         7,217         5,997
   Impairment of oil and gas properties                             -             -       119,715
   Depletion                                                   25,125        40,513        97,851
   Abandoned property                                           2,166             -             -
                                                            ---------     ---------     ---------

                                                              192,070       178,895       366,001
                                                            ---------     ---------     ---------

Net income (loss)                                           $ 261,490     $  69,459     $(160,396)
                                                            =========     =========     =========

Allocation of net income (loss):
   Managing general partner                                 $   2,615     $     695     $  (1,604)
                                                            =========     =========     =========

   Limited partners                                         $ 258,875     $  68,764     $(158,792)
                                                            =========     =========     =========

Net income (loss) per limited partnership interest          $   75.89     $   20.16     $  (46.55)
                                                            =========     =========     =========





   The accompanying notes are an integral part of these financial statements.



                                       4
   1126


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                  Managing
                                                   general        Limited
                                                   partner        partners        Total
                                                  ---------      ---------      ---------
                                                                       

Partners' capital at January 1, 1998              $   7,326      $ 726,841      $ 734,167

    Distributions                                      (777)       (76,894)       (77,671)

    Net loss                                         (1,604)      (158,792)      (160,396)
                                                  ---------      ---------      ---------

Partners' capital at December 31, 1998                4,945        491,155        496,100

    Distributions                                      (746)       (73,875)       (74,621)

    Net income                                          695         68,764         69,459
                                                  ---------      ---------      ---------

Partners' capital at December 31, 1999                4,894        486,044        490,938

    Distributions                                    (2,604)      (257,772)      (260,376)

    Net income                                        2,615        258,875        261,490
                                                  ---------      ---------      ---------

Partners' capital at December 31, 2000            $   4,905      $ 487,147      $ 492,052
                                                  =========      =========      =========





   The accompanying notes are an integral part of these financial statements.



                                       5
   1127


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                               2000          1999            1998
                                                            ---------      ---------      ---------
                                                                                 

Cash flows from operating activities:
  Net income (loss)                                         $ 261,490      $  69,459      $(160,396)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
       Impairment of oil and gas properties                         -              -        119,715
       Depletion                                               25,125         40,513         97,851
       Gain on disposition of assets                           (5,650)             -         (2,175)
  Changes in assets and liabilities:
       Accounts receivable                                    (26,341)       (16,186)        10,141
       Accounts payable                                        (3,028)         2,588         (7,979)
                                                            ---------      ---------      ---------

          Net cash provided by operating activities           251,596         96,374         57,157
                                                            ---------      ---------      ---------

Cash flows from investing activities:
  Additions to oil and gas properties                          (2,067)        (3,851)        (5,337)
  Proceeds from disposition of assets                           5,650          3,435          2,175
                                                            ---------      ---------      ---------

          Net cash provided by (used in)
             investing activities                               3,583           (416)        (3,162)
                                                            ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                             (260,376)       (74,621)       (77,671)
                                                            ---------      ---------      ---------

Net increase (decrease) in cash                                (5,197)        21,337        (23,676)
Cash at beginning of year                                      56,353         35,016         58,692
                                                            ---------      ---------      ---------

Cash at end of year                                         $  51,156      $  56,353      $  35,016
                                                            =========      =========      =========





   The accompanying notes are an integral part of these financial statements.



                                       6
   1128


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 88-C Conv., L.P. (the "Partnership") was organized in
1988 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1989. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   1129


        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non- partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $119,715 related to
its proved oil and gas properties during 1998.


                                       8
   1130


NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $35,215 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                   2000            1999          1998
                                                                 ---------      ---------     ---------
                                                                                     

Net income (loss) per statements of operations                   $ 261,490      $  69,459     $(160,396)
Depletion and depreciation provisions for tax reporting
   purposes less than amounts for financial reporting
   purposes                                                         21,929         37,157        94,995
Impairment of oil and gas properties for financial
   reporting purposes                                                    -              -       119,715
Other, net                                                            (822)         3,106        (4,638)
                                                                 ---------      ---------     ---------

         Net income per Federal income tax returns               $ 282,597      $ 109,722     $  49,676
                                                                 =========      =========     =========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                           2000             1999              1998
                                       ----------       -----------       ----------
                                                                 

Development costs                      $    2,067       $     3,851       $    5,337
                                       ==========       ===========       ==========


        Capitalized oil and gas properties consist of the following:



                                                  2000                1999
                                               -----------        -----------
                                                            

Proved properties:
  Property acquisition costs                   $   124,434        $   128,446
  Completed wells and equipment                  2,333,684          2,385,378
                                               -----------        -----------

                                                 2,458,118          2,513,824
Accumulated depletion                           (2,078,258)        (2,110,906)
                                               -----------        -----------

        Net oil and gas properties             $   379,860        $   402,918
                                               ===========        ===========




                                       9
   1131


NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                                  2000           1999           1998
                                                                --------       --------       --------
                                                                                     

Payment of lease operating and supervision
  charges in accordance with standard industry
  operating agreements                                          $ 58,509       $ 56,225       $ 54,996

Reimbursement of general and administrative expenses            $  9,514       $  1,096       $  2,651


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 88-C, L.P. and the Partnership (the "Partnerships") are parties
to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:



                                                            Pioneer USA (1)  Partnerships (2)
                                                            ---------------  ----------------
                                                                       

Revenues:
  Proceeds from disposition of depreciable
     properties                                                 9.09091%        90.90909%
  All other revenues                                          24.242425%       75.757575%
Costs and expenses:
  Lease acquisition costs, drilling and completion
     costs and all other costs                                  9.09091%        90.90909%
  Operating costs, direct costs and general and
     administrative expenses                                  24.242425%       75.757575%


(1)   Excludes Pioneer USA's 1% general partner ownership which is allocated at
      the Partnership level and ten limited partner interests owned by Pioneer
      USA.

(2)   The allocation between the Partnership and Parker & Parsley 88-C, L.P. is
      58.387538% and 41.612462%, respectively.

NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       10
   1132




                                                   Oil and NGLs          Gas
                                                      (bbls)            (mcf)
                                                   ------------      ---------
                                                               

Net proved reserves at January 1, 1998                181,762          227,096
Revisions                                             (75,078)         (70,056)
Production                                            (14,859)         (19,764)
                                                    ---------        ---------

Net proved reserves at December 31, 1998               91,825          137,276
Revisions                                             124,253          193,483
Production                                            (14,136)         (21,119)
                                                    ---------        ---------

Net proved reserves at December 31, 1999              201,942          309,640
Revisions                                              35,970           23,002
Production                                            (15,453)         (19,618)
                                                    ---------        ---------

Net proved reserves at December 31, 2000              222,459          313,024
                                                    =========        =========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.56 per barrel of NGLs and $7.78 per mcf of gas,
discounted at 10% was approximately $1,724,000 and undiscounted was
approximately $3,597,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                             For the years ended December 31,
                                                                        ----------------------------------------
                                                                          2000            1999            1998
                                                                        --------        --------        --------
                                                                                     (in thousands)
                                                                                               

Oil and gas producing activities:
   Future cash inflows                                                  $  7,379        $  5,029        $  1,007
   Future production costs                                                (3,782)         (2,920)           (784)
                                                                        --------        --------        --------

                                                                           3,597           2,109             223
   10% annual discount factor                                             (1,873)           (998)            (69)
                                                                        --------        --------        --------

   Standardized measure of discounted future net cash flows             $  1,724        $  1,111        $    154
                                                                        ========        ========        ========




                                       11
   1133




                                                                  For the years ended December 31,
                                                              --------------------------------------
                                                                2000           1999           1998
                                                              -------        -------        -------
                                                                          (in thousands)
                                                                                   

Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs                  $  (292)       $  (115)       $   (58)
  Net changes in prices and production costs                      661            496           (461)
  Revisions of previous quantity estimates                        275            900            (94)
  Accretion of discount                                           111             15             72
  Changes in production rates, timing and other                  (142)          (339)           (26)
                                                              -------        -------        -------

  Change in present value of future net revenues                  613            957           (567)
                                                              -------        -------        -------

  Balance, beginning of year                                    1,111            154            721
                                                              -------        -------        -------

  Balance, end of year                                        $ 1,724        $ 1,111        $   154
                                                              =======        =======        =======



NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                     2000            1999            1998
                                                   --------        --------        --------
                                                                          

Plains Marketing, L.P.                                52%             46%               -
Genesis Crude Oil, L.P.                                -               -               51%
Western Gas Resources, Inc.                            4%              6%              21%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $21,565 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's



                                       12
   1134


        revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $3,411,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.



                                       13


   1135


                        PARKER & PARSLEY 88-C CONV., L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
    RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 80% to $443,642 for 2000 as
compared to $246,242 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 10,646 barrels
of oil, 4,807 barrels of natural gas liquids ("NGLs") and 19,618 mcf of gas were
sold, or 18,723 barrel of oil equivalents ("BOEs"). In 1999, 9,260 barrels of
oil, 4,876 barrels of NGLs and 21,119 mcf of gas were sold, or 17,656 BOEs. Due
to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.09, or 70%, from
$17.24 in 1999 to $29.33 in 2000. The average price received per barrel of NGLs
increased $5.41, or 52%, from $10.42 in 1999 to $15.83 in 2000. The average
price received per mcf of gas increased 66% from $1.70 in 1999 to $2.82 in 2000.
The market price for oil and gas has been extremely volatile in the past decade,
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gain on disposition of assets of $5,650 recognized in 2000 was due to equipment
credits received from salvage income of $4,703 on one well plugged and abandoned
during the current year and $947 on one fully depleted well.

Total costs and expenses increased in 2000 to $192,070 as compared to $178,895
in 1999, an increase of $13,175, or 7%. The increase was primarily due to
increases in production costs, general and administrative expenses ("G&A") and
abandoned property costs, offset by a decline in depletion.

Production costs were $151,650 in 2000 and $131,165 in 1999, resulting in a
$20,485 increase, or 16%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
and workover costs incurred to stimulate well production.

Abandoned property costs of $2,166 during 2000 were related to the plugging and
abandonment of one well during the current year.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
82% from $7,217 in 1999 to $13,129 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $9,514 in 2000 and $1,096 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $25,125 in 2000 as compared to $40,513 in 1999, representing a
decrease of $15,388, or 38%. This decrease was primarily due to a 26,409 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices, offset by an increase in oil production of 1,386 barrels for the period
ended December 31, 2000 compared to the same period in 1999.


   1136


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 23% to $246,242 from
$200,460 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 9,260 barrels of oil,
4,876 barrels of NGLs and 21,119 mcf of gas were sold, or 17,656 BOEs. In 1998,
10,457 barrels of oil, 4,402 barrels of NGLs and 19,764 mcf of gas were sold, or
18,153 BOEs.

The average price received per barrel of oil increased $3.94, or 30%, from
$13.30 in 1998 to $17.24 in 1999. The average price received per barrel of NGLs
increased $3.48, or 50%, from $6.94 in 1998 to $10.42 in 1999. The average price
received per mcf of gas increased 10% from $1.55 in 1998 to $1.70 in 1999.

A gain on disposition of assets of $2,175 was recognized during 1998 from
equipment credits on a well plugged and abandoned in 1997.

Total costs and expenses decreased in 1999 to $178,895 as compared to $366,001
in 1998, a decrease of $187,106, or 51%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $131,165 in 1999 and $142,438 in 1998, resulting in an
$11,273 decrease, or 8%. The decrease was due to declines in well maintenance
costs, workover expenses and ad valorem taxes, offset by an increase in
production taxes due to increased oil and gas revenues.

During this period, G&A increased 20% from $5,997 in 1998 to $7,217 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $1,096 in
1999 and $2,651 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long- Lived Assets and for Long-Lived Assets
to be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $119,715 related to its oil and gas properties during 1998.

Depletion was $40,513 in 1999 compared to $97,851 in 1998, representing a
decrease of $57,338, or 59%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 79,930 barrels of oil
during 1999 as a result of higher commodity prices, a reduction in the
Partnership's net depletable basis from charges taken in accordance with SFAS
121 during the fourth quarter of 1998 and a decline in oil production of 1,197
barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.



   1137


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $155,222 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $199,556, offset by increases in production costs paid
of $20,485, G&A expenses paid of $5,912, abandoned property costs paid of $2,166
and working capital of $15,771. The increase in oil and gas receipts resulted
from the increase in commodity prices during 2000 which contributed an
additional $164,214 to oil and gas receipts and an increase of $35,342 resulting
from the increase in production during 2000. The increase in production costs
was primarily due to increased production taxes associated with higher oil and
gas prices and additional well maintenance and workover costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds from disposition of assets of $5,650 recognized in 2000 was due to
equipment credits received from salvage income of $4,703 on one well plugged and
abandoned during the current year and $947 on one fully depleted well. Proceeds
from disposition of assets of $3,435 during 1999 were received from equipment
credits on active wells.

Net Cash Used in Financing Activities

For 2000, cash distributions to the partners were $260,376, of which $2,604 was
distributed to the managing general partner and $257,772 to the limited
partners. In 1999, cash distributions to the partners were $74,621, of which
$746 was distributed to the managing general partner and $73,875 to the limited
partners.




   1138




                        PARKER & PARSLEY 88-C CONV., L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   95,029   $  443,642   $  246,242   $  200,460   $  284,284   $  372,187
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  119,715   $  137,839   $    4,494
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   51,906   $  261,490   $   69,459   $ (160,396)  $  (84,748)  $  128,417
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      519   $    2,615   $      695   $   (1,604)  $     (847)  $    1,284
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   51,387   $  258,875   $   68,764   $ (158,792)  $  (83,901)  $  127,133
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    15.07   $    75.89   $    20.16   $   (46.55)  $   (24.60)  $    37.27
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    16.38   $    75.57   $    21.66   $    22.54   $    44.49   $    47.64
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  495,584   $  497,979   $  499,893   $  502,467   $  748,513   $  982,497
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1139
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 88-C, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
88-C, L.P., and supplements the proxy statement/prospectus dated        , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc.,
by which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 88-C, L.P.:

    o  A table containing:

       --  the aggregate initial investment by the limited partners


       --  the aggregate historical limited partner distributions through
           July 31, 2001

       --  the merger value attributable to partnership interests of limited
           partners, excluding Pioneer USA

       --  the merger value per $1,000 limited partner investment

       --  the merger value per $1,000 limited partner investment as a multiple
           of distributions for the past four quarterly distributions including
           the distribution in July 2001


       --  the book value per $1,000 limited partner investment as of March 31,
           2001 and as of December 31, 2000


       --  the going concern value per $1,000 limited partner investment

       --  the liquidation value per $1,000 limited partner investment


       --  the ordinary tax loss per $1,000 limited partner investment in year
           of initial investment


    o  Information about:

       --  the legal opinion for the limited partners

       --  the term of the partnership

    o  The partnership's financial statements, including management's discussion
       and analysis of financial condition and results of operations, for the
       three months ended March 31, 2001

    o  The partnership's financial statements, including management's discussion
       and analysis of financial condition and results of operations, for the
       year ended December 31, 2000


    o  Selected historical financial data for the partnership for the three
       months ended March 31, 2001 and 2000 and the five years ended December
       31, 2000

                                      -1-
   1140
                           PARKER & PARSLEY 88-C, L.P.

                         SUPPLEMENTAL INFORMATION TABLE





                                                                                            
Aggregate Initial Investment by the Limited Partners(a)                                        $   2,431

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                    $   2,558

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $     664
USA(a),(b)

Merger Value per $1,000 Limited Partner Investment(b), (c)                                     $  273.81

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.29 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

     --  as of March 31, 2001(c)                                                               $  135.53

     --  as of December 31, 2000(c)                                                            $  140.76

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                              $  255.07

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                $  265.75

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c),      $     149
(f)



----------

(a) Stated in thousands.


(b) The merger value for the partnership is equal to the sum of the present
    value of estimated future net revenues from the partnership's estimated oil
    and gas reserves and its net working capital, in each case as of March 31,
    2001, less its pro rata share, based on its reserve value, of the estimated
    expenses and fees of the mergers of all of the partnerships and less the
    cash distribution on or about July 9, 2001, by the partnership to its
    partners.

(c) Interests in some partnerships were sold in units at prices other than
    $1,000. We have presented this information based on a $1,000 initial
    investment for ease of use and comparison among partnerships. You should not
    assume that the amount shown per $1,000 investment is the same as the value
    or amount attributable to a single unit investment.

(d) The going concern value for the partnership is based upon: (1) the sum of
    (A) the estimated net cash flow from the sale of the partnership's reserves
    during a 10-year operating period and (B) the estimated residual value from
    the sale of the partnership's remaining reserves at the end of the operating
    period, in each case using the same pricing and discount rate as in the
    merger value calculation, less (2) partnership level general and
    administrative expenses.

(e) The liquidation value for the partnership is based upon the sale of the
    partnership's reserves at the reserve value, less liquidation expenses which
    are estimated to be the sum of (1) the partnership's pro rata share of the
    merger expenses and fees described in footnote (b) above and (2) 3% of the
    partnership's reserve value. The liquidation expenses represent estimated
    costs to retain an investment banker or broker to sell the assets of the
    partnership and the legal and other closing costs associated with such
    transaction, including the wind-down costs of the partnership.

(f) Your ability to use your distributive share of the partnership's loss to
    offset your other income may have been subject to certain limitations at
    your level as a partner, and you may therefore wish to consult your tax
    advisor to determine the additional value, if any, actually realized by you
    in your particular circumstances.

          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

    The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

    The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   1141



                           PARKER & PARSLEY 88-C, L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   1142


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS



                                                     March 31,     December 31,
                                                       2001            2000
                                                   ------------    ------------
                                                    (Unaudited)
                                                             
                 ASSETS

Current assets:
  Cash                                             $     29,255    $     31,689
  Accounts receivable - oil and gas sales                41,231          47,902
                                                   ------------    ------------
        Total current assets                             70,486          79,591
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                1,752,104       1,751,887
Accumulated depletion                                (1,485,742)     (1,481,594)
                                                   ------------    ------------
        Net oil and gas properties                      266,362         270,293
                                                   ------------    ------------
                                                   $    336,848    $    349,884
                                                   ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $      4,060    $      4,246

Partners' capital:
  Managing general partner                                3,314           3,443
  Limited partners (2,431 interests)                    329,474         342,195
                                                   ------------    ------------
                                                        332,788         345,638
                                                   ------------    ------------
                                                   $    336,848    $    349,884
                                                   ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2

   1143


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                     Three months ended
                                                          March 31,
                                                 ------------   ------------
                                                     2001            2000
                                                 ------------   ------------
                                                          
Revenues:
  Oil and gas                                    $     79,813   $     68,027
  Interest                                                519            497
                                                 ------------   ------------
                                                       80,332         68,524
                                                 ------------   ------------
Costs and expenses:
  Oil and gas production                               25,472         24,290
  General and administrative                            2,394          2,041
  Depletion                                             4,148          4,983
                                                 ------------   ------------
                                                       32,014         31,314
                                                 ------------   ------------
Net income                                       $     48,318   $     37,210
                                                 ============   ============
Allocation of net income:
  Managing general partner                       $        483   $        372
                                                 ============   ============
  Limited partners                               $     47,835   $     36,838
                                                 ============   ============
Net income per limited partnership interest      $      19.68   $      15.15
                                                 ============   ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3

   1144


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                       Managing
                                        general      Limited
                                        partner      partners       Total
                                      ----------    ----------    ----------
                                                         
Balance at January 1, 2001            $    3,443    $  342,195    $  345,638

    Distributions                           (612)      (60,556)      (61,168)

    Net income                               483        47,835        48,318
                                      ----------    ----------    ----------

Balance at March 31, 2001             $    3,314    $  329,474    $  332,788
                                      ==========    ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.




                                        4

   1145


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                             Three months ended
                                                                 March 31,
                                                          ------------------------
                                                             2001          2000
                                                          ----------    ----------
                                                                  
Cash flows from operating activities:
  Net income                                              $   48,318    $   37,210
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                               4,148         4,983
  Changes in assets and liabilities:
       Accounts receivable                                     6,671         1,036
       Accounts payable                                         (186)          154
                                                          ----------    ----------
           Net cash provided by operating activities          58,951        43,383
                                                          ----------    ----------
Cash flows from investing activities:
  Additions to oil and gas properties                           (337)         (439)
  Proceeds from disposition of assets                            120            --
                                                          ----------    ----------
           Net cash used in investing activities                (217)         (439)
                                                          ----------    ----------
Cash flows used in financing activities:
  Cash distributions to partners                             (61,168)      (40,228)
                                                          ----------    ----------
Net increase (decrease) in cash                               (2,434)        2,716
Cash at beginning of period                                   31,689        35,943
                                                          ----------    ----------
Cash at end of period                                     $   29,255    $   38,659
                                                          ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   1146



                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley 88-C, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 17% to $79,813 for the three
months ended March 31, 2001 as compared to $68,027 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 1,537
barrels of oil, 674 barrels of natural gas liquids ("NGLs") and 2,517 mcf of gas
were sold, or 2,631 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 1,930 barrels of oil, 799 barrels of NGLs and 3,392 mcf of



                                        6
   1147



gas were sold, or 3,294 BOEs. Of the decrease, 631 BOEs are attributable to
three wells reaching payout pursuant to the terms of the farmout agreements
which reduced the Partnership's net revenue interest in the wells.

The average price received per barrel of oil increased $3.74, or 14%, from
$26.37 for the three months ended March 31, 2000 to $30.11 for the same period
in 2001. The average price received per barrel of NGLs increased $5.19, or 36%,
from $14.26 for the three months ended March 31, 2000 to $19.45 for the same
period in 2001. The average price received per mcf of gas increased 378% from
$1.70 during the three months ended March 31, 2000 to $8.12 for the same period
in 2001. The market price for oil and gas has been extremely volatile in the
past decade, and management expects a certain amount of volatility to continue
in the foreseeable future. The Partnership may therefore sell its future oil and
gas production at average prices lower or higher than that received during the
three months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $32,014 for the three months ended March
31, 2001 as compared to $31,314 for the same period in 2000, an increase of
$700, or 2%. This increase was due to increases in production costs and general
and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $25,472 for the three months ended March 31, 2001 and
$24,290 for the same period in 2000 resulting in a $1,182 increase, or 5%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices and additional workover costs incurred to stimulate well
production, offset by a decline in lease operating and production taxes
attributable to the wells that reached payout pursuant to the terms of the
farmout agreements as noted above.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 17% from $2,041 for the three months ended March 31, 2000 to $2,394
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $4,148 for the three months ended March 31, 2001 compared to
$4,983 for the same period in 2000, a decrease of $835, or 17%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices and a decline
in oil production of 393 barrels for the three months ended March 31, 2001 as
compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $15,568 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $11,808 and a
reduction of $5,295 in working capital, offset by increases in production costs



                                        7

   1148


of $1,182 and G&A expenses of $353. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $33,173 to oil and gas receipts, offset by $21,365 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional workover costs incurred
to stimulate well production, offset by a decline in lease operating and
production taxes attributable to the wells that reached payout pursuant to the
terms of the farmout agreements. The increase in G&A was primarily due to an
increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active
properties.

Proceeds from disposition of assets of $120 recognized during the three months
ended March 31, 2001 were due to equipment credits received on one active well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $61,168, of which $612 was distributed to the managing general partner and
$60,556 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $40,228, of which $402 was distributed to the
managing general partner and $39,826 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.

                                        8



   1149
                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999


   1150






                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 88-C, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 88-C, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 88-C, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                               Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   1151


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                     2000           1999
                                                 -----------    -----------
                     ASSETS

                                                          
Current assets:
  Cash                                           $    31,689    $    35,943
  Accounts receivable - oil and gas sales             47,902         28,942
                                                 -----------    -----------

           Total current assets                       79,591         64,885
                                                 -----------    -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method             1,751,887      1,791,588
Accumulated depletion                             (1,481,594)    (1,504,855)
                                                 -----------    -----------

           Net oil and gas properties                270,293        286,733
                                                 -----------    -----------

                                                 $   349,884    $   351,618
                                                 ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $     4,246    $     6,404

Partners' capital:
  Managing general partner                             3,443          3,439
  Limited partners (2,431 interests)                 342,195        341,775
                                                 -----------    -----------

                                                     345,638        345,214
                                                 -----------    -----------

                                                 $   349,884    $   351,618
                                                 ===========    ===========



The accompanying notes are an integral part of these financial statements.



                                       3
   1152


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                       2000        1999        1998
                                                     ---------   ---------   ---------

                                                                      
Revenues:
  Oil and gas                                        $ 316,382   $ 175,483     142,874
  Interest                                               2,805       1,335       1,945
  Gain on disposition of assets                          4,027          --       1,550
                                                     ---------   ---------   ---------

                                                       323,214     176,818     146,369
                                                     ---------   ---------   ---------

Costs and expenses:
  Oil and gas production                               108,093      93,481     101,514
  General and administrative                             9,672       5,434       4,303
  Impairment of oil and gas properties                      --          --      85,160
  Depletion                                             17,913      28,843      69,935
  Abandoned property                                     1,544          --          --
                                                     ---------   ---------   ---------

                                                       137,222     127,758     260,912
                                                     ---------   ---------   ---------

Net income (loss)                                    $ 185,992   $  49,060   $(114,543)
                                                     =========   =========   =========

Allocation of net income (loss):
  Managing general partner                           $   1,860   $     491   $  (1,145)
                                                     =========   =========   =========

  Limited partners                                   $ 184,132   $  48,569   $(113,398)
                                                     =========   =========   =========

Net income (loss) per limited partnership interest   $   75.74   $   19.98   $  (46.65)
                                                     =========   =========   =========



The accompanying notes are an integral part of these financial statements.




                                       4
   1153


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                Managing
                                                 general      Limited
                                                 partner      partners       Total
                                                 ---------    ---------    ---------
                                                                 
Partners' capital at January 1, 1998             $   5,179    $ 514,055    $ 519,234

     Distributions                                    (554)     (54,801)     (55,355)

     Net loss                                       (1,145)    (113,398)    (114,543)
                                                 ---------    ---------    ---------

Partners' capital at December 31, 1998               3,480      345,856      349,336

     Distributions                                    (532)     (52,650)     (53,182)

     Net income                                        491       48,569       49,060
                                                 ---------    ---------    ---------

Partners' capital at December 31, 1999               3,439      341,775      345,214

     Distributions                                  (1,856)    (183,712)    (185,568)

     Net income                                      1,860      184,132      185,992
                                                 ---------    ---------    ---------

Partners' capital at December 31, 2000           $   3,443    $ 342,195    $ 345,638
                                                 =========    =========    =========



The accompanying notes are an integral part of these financial statements.



                                       5
   1154


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                           2000         1999         1998
                                                         ---------    ---------    ---------

                                                                          
Cash flows from operating activities:
    Net income (loss)                                    $ 185,992    $  49,060    $(114,543)
    Adjustments to reconcile net income (loss) to
       net cash provided by operating activities:
          Impairment of oil and gas properties                  --           --       85,160
          Depletion                                         17,913       28,843       69,935
          Gain on disposition of assets                     (4,027)          --       (1,550)
    Changes in assets and liabilities:
          Accounts receivable                              (18,960)     (11,532)       7,229
          Accounts payable                                  (2,158)       1,866       (5,686)
                                                         ---------    ---------    ---------

             Net cash provided by operating activities     178,760       68,237       40,545
                                                         ---------    ---------    ---------

Cash flows from investing activities:
    Additions to oil and gas properties                     (1,473)      (2,744)      (3,804)
    Proceeds from disposition of assets                      4,027        2,448        1,550
                                                         ---------    ---------    ---------

             Net cash provided by (used in)
                investing activities                         2,554         (296)      (2,254)
                                                         ---------    ---------    ---------

Cash flows used in financing activities:
    Cash distributions to partners                        (185,568)     (53,182)     (55,355)
                                                         ---------    ---------    ---------

Net increase (decrease) in cash                             (4,254)      14,759      (17,064)
Cash at beginning of year                                   35,943       21,184       38,248
                                                         ---------    ---------    ---------

Cash at end of year                                      $  31,689    $  35,943    $  21,184
                                                         =========    =========    =========



The accompanying notes are an integral part of these financial statements.



                                       6
   1155


                           PARKER & PARSLEY 88-C, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 88-C, L.P. (the "Partnership") is a limited partnership
organized in 1988 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the


                                       7
   1156


respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.  IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $85,160 related to its
proved oil and gas properties during 1998.



                                       8
   1157


NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $24,633 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                                  2000         1999        1998
                                                                ---------    ---------   ---------

                                                                                
      Net income (loss) per statements of operations            $ 185,992    $  49,060   $(114,543)
      Depletion and depreciation provisions for tax reporting
        purposes less than amounts for financial reporting
        purposes                                                   15,635       26,451      67,898
      Impairment of oil and gas properties for financial
        reporting purposes                                             --           --      85,160
      Other, net                                                     (560)       2,209      (3,307)
                                                                ---------    ---------   ---------

              Net income per Federal income tax returns         $ 201,067    $  77,720   $  35,208
                                                                =========    =========   =========



NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:




                                                                              2000                1999                 1998
                                                                         -------------        -------------       -------------
                                                                                                         
      Development costs                                                  $       1,473       $       2,744        $       3,804
                                                                          ============        ============         ============


        Capitalized oil and gas properties consist of the following:




                                               2000           1999
                                           -----------    -----------
                                                    
      Proved properties:
        Property acquisition costs         $    88,684    $    91,543
        Completed wells and equipment        1,663,203      1,700,045
                                           -----------    -----------

                                             1,751,887      1,791,588
      Accumulated depletion                 (1,481,594)    (1,504,855)
                                           -----------    -----------

              Net oil and gas properties   $   270,293    $   286,733
                                           ===========    ===========




                                       9
   1158



NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:





                                                    2000      1999      1998
                                                   -------   -------   -------
                                                              
     Payment of lease operating and supervision
        charges in accordance with standard
        industry operating agreements              $41,699   $40,071   $39,194

     Reimbursement of general and administrative
        expenses                                   $ 6,776   $   782   $ 1,889



        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
Parker & Parsley 88-C Conv., L.P. and the Partnership (the "Partnerships") are
parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:




                                                              Pioneer USA(1)   Partnerships (2)
                                                              --------------   ----------------
                                                                         
      Revenues:
        Proceeds from disposition of depreciable
            properties                                             9.09091%       90.90909%
        All other revenues                                        24.242425%      75.757575%

      Costs and expenses:
        Lease acquisition costs, drilling and completion
            costs and all other costs                              9.09091%       90.90909%
        Operating costs, direct costs and general and
            administrative expenses                               24.242425%      75.757575%


      (1)     Excludes Pioneer USA's 1% general partner ownership which is
              allocated at the Partnership level and five limited partner
              interests owned by Pioneer USA.

      (2)     The allocation between the Partnership and Parker & Parsley 88-C
              Conv., L.P. is 41.612462% and 58.387538%, respectively.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       10
   1159






                                                           Oil and NGLs     Gas
                                                              (bbls)       (mcf)
                                                             --------    --------

                                                                 
     Net proved reserves at January 1, 1998                   129,544     161,856
     Revisions                                                (53,503)    (49,926)
     Production                                               (10,596)    (14,091)
                                                             --------    --------

     Net proved reserves at December 31, 1998                  65,445      97,839
     Revisions                                                 88,560     137,904
     Production                                               (10,071)    (15,049)
                                                             --------    --------

     Net proved reserves at December 31, 1999                 143,934     220,694
     Revisions                                                 25,631      16,368
     Production                                               (11,023)    (13,979)
                                                             --------    --------

     Net proved reserves at December 31, 2000                 158,542     223,083
                                                             ========    ========


        As of December 31, 2000 the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.56 per barrel of NGLs and $7.78 per mcf of gas,
discounted at 10% was approximately $1,229,000 and undiscounted was $2,564,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.





                                                                  For the years ended December 31,
                                                                  --------------------------------
                                                                     2000       1999       1998
                                                                   -------    -------    -------
                                                                           (in thousands)
                                                                                
Oil and gas producing activities:
   Future cash inflows                                             $ 5,259    $ 3,584    $   717
   Future production costs                                          (2,695)    (2,081)      (558)
                                                                   -------    -------    -------

                                                                     2,564      1,503        159
   10% annual discount factor                                       (1,335)      (711)       (49)
                                                                   -------    -------    -------

   Standardized measure of discounted future net cash flows        $ 1,229    $   792    $   110
                                                                   =======    =======    =======




                                       11
   1160





                                                                   For the years ended December 31,
                                                                   --------------------------------
                                                                      2000       1999       1998
                                                                   -------    -------    -------
                                                                            (in thousands)
                                                                                
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs                   $  (208)   $   (82)   $   (41)
      Net changes in prices and production costs                       471        354       (328)
      Revisions of previous quantity estimates                         196        641        (67)
      Accretion of discount                                             79         11         51
      Changes in production rates, timing and other                   (101)      (242)       (19)
                                                                   -------    -------    -------

      Change in present value of future net revenues                   437        682       (404)
                                                                   -------    -------    -------

      Balance, beginning of year                                       792        110        514
                                                                   -------    -------    -------

      Balance, end of year                                         $ 1,229    $   792    $   110
                                                                   =======    =======    =======



NOTE 8.  MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:




                                                        2000                1999               1998
                                                      -------             -------            --------
                                                                                    
                    Plains Marketing, L.P.                  52%                45%                 -
                    Genesis Crude Oil, L.P.                  -                  -                 51%
                    Western Gas Resources, Inc.              4%                 6%                21%



        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $15,388 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's




                                       12
   1161


        revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $2,431,000. Pioneer USA is required to contribute amounts equal to 1% of
        initial Partnership capital less commission and organization and
        offering costs allocated to the limited partners and to contribute
        amounts necessary to pay costs and expenses allocated to it under the
        Partnership agreement to the extent its share of revenues does not cover
        such costs.




                                       13
   1162


                           PARKER & PARSLEY 88-C, L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 80% to $316,382 for 2000 as
compared to $175,483 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 7,593 barrels of
oil, 3,430 barrels of natural gas liquids ("NGLs") and 13,979 mcf of gas were
sold, or 13,353 barrel of oil equivalents ("BOEs"). In 1999, 6,595 barrels of
oil, 3,476 barrels of NGLs and 15,049 mcf of gas were sold, or 12,579 BOEs. Due
to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.09, or 70%, from
$17.24 in 1999 to $29.33 in 2000. The average price received per barrel of NGLs
increased $5.41, or 52%, from $10.42 in 1999 to $15.83 in 2000. The average
price received per mcf of gas increased 66% from $1.70 in 1999 to $2.82 in 2000.
The market price for oil and gas has been extremely volatile in the past decade,
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gain on disposition of assets of $4,027 recognized in 2000 was due to salvage
income from equipment credits of $3,352 on one well plugged and abandoned during
the current year and $675 on one fully depleted well.

Total costs and expenses increased in 2000 to $137,222 as compared to $127,758
in 1999, an increase of $9,464, or 7%. The increase was primarily due to
increases in production costs, general and administrative expenses ("G&A") and
abandoned property costs, offset by a decline in depletion.

Production costs were $108,093 in 2000 and $93,481 in 1999, resulting in a
$14,612, or 16%, increase. The increase was primarily due to higher production
taxes associated with higher oil and gas prices, additional well maintenance and
workover costs incurred to stimulate well production.

Abandoned property costs of $1,544 during 2000 were related to the plugging and
abandonment of one well during the current year.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
78% from $5,434 in 1999 to $9,672 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $6,776 in 2000 and $782 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

                2000 as compared to $28,843 in 1999, representing a decrease of
                $10,930, or 38%. This decrease was primarily due to a 18,820
                barrels of oil increase in proved reserves during 2000 as a
                result of higher commodity prices, offset by an increase in oil
                production of 998 barrels for the period ended December 31, 2000
                compared to the same period in 1999.



   1163


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 23% to $175,483 from
$142,874 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 6,595 barrels of oil,
3,476 barrels of NGLs and 15,049 mcf of gas were sold, or 12,579 BOEs. In 1998,
7,453 barrels of oil, 3,143 barrels of NGLs and 14,091 mcf of gas were sold, or
12,945 BOEs.

The average price received per barrel of oil increased $3.94, or 30%, from
$13.30 in 1998 to $17.24 in 1999. The average price received per barrel of NGLs
increased $3.48, or 50%, from $6.94 in 1998 to $10.42 in 1999. The average price
received per mcf of gas increased 10% from $1.55 in 1998 to $1.70 in 1999.

A gain on disposition of assets of $1,550 was recognized during 1998 from
equipment credits on a well plugged and abandoned in 1997.

Total costs and expenses decreased in 1999 to $127,758 as compared to $260,912
in 1998, a decrease of $133,154, or 51%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $93,481 in 1999 and $101,514 in 1998, resulting in an
$8,033, or 8%, decrease. The decrease was due to declines in well maintenance
costs, workover expenses and ad valorem taxes, offset by an increase in
production taxes due to increased oil and gas revenues.

During this period, G&A increased 26% from $4,303 in 1998 to $5,434 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $782 in 1999
and $1,889 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $85,160 related to its oil and gas properties during 1998.

Depletion was $28,843 in 1999 compared to $69,935 in 1998, representing a
decrease of $41,092, or 59%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 56,967 barrels of oil
during 1999 due to higher commodity prices, a reduction in the Partnership's net
depletable basis from charges taken in accordance with SFAS 121 during the
fourth quarter of 1998 and a decline in oil production of 858 barrels for the
period ended December 31, 1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.



   1164



Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $110,523 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $142,369, offset by increases in production costs paid
of $14,612, G&A expenses paid of $4,238, abandoned property costs paid of $1,544
and working capital of $11,452. The increase in oil and gas receipts resulted
from the increase in commodity prices during 2000 which contributed an
additional $116,842 to oil and gas receipts and an increase of $25,527 resulting
from an increase in production during 2000. The increase in production costs was
primarily due to increased production taxes associated with higher oil and gas
prices and additional well maintenance and workover costs incurred to stimulate
well production. The increase in G&A was primarily due to higher percentage of
the managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds from disposition of assets of $4,027 during 2000 were due to salvage
income from equipment credits of $3,352 on one well plugged and abandoned during
the current year and $675 on one fully depleted well. Proceeds from disposition
of assets of $2,448 during 1999 were from equipment credits on active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $185,568, of which $1,856 was
distributed to the managing general partner and $183,712 to the limited
partners. In 1999, cash distributions to the partners were $53,182, of which
$532 was distributed to the managing general partner and $52,650 to the limited
partners.


   1165



                           PARKER & PARSLEY 88-C, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   68,027   $  316,382   $  175,483   $  142,874   $  202,605   $  265,257
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   85,160   $   98,341   $    3,203
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   37,210   $  185,992   $   49,060   $ (114,543)  $  (60,727)  $   91,333
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      372   $    1,860   $      491   $   (1,145)  $     (607)  $      913
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   36,838   $  184,132   $   48,569   $ (113,398)  $  (60,120)  $   90,420
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    15.15   $    75.74   $    19.98   $   (46.65)  $   (24.73)  $    37.19
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    16.38   $    75.57   $    21.66   $    22.54   $    44.49   $    47.64
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  348,754   $  349,884   $  351,618   $  353,874   $  529,458   $  696,541
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1166
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                              --------------------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                              --------------------


     This document contains important information specific to Parker & Parsley
Producing Properties 88-A, L.P., and supplements the proxy statement/prospectus
dated       , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Producing Properties 88-A, L.P.:

         o  A table containing:

            --  the aggregate initial investment by the limited partners


            --  the aggregate historical limited partner distributions through
                July 31, 2001

            --  the merger value attributable to partnership interests of
                limited partners, excluding Pioneer USA

            --  the merger value per $1,000 limited partner investment

            --  the merger value per $1,000 limited partner investment as a
                multiple of distributions for the past four quarterly
                distributions including the distribution in July 2001


            --  the book value per $1,000 limited partner investment as of
                March 31, 2001 and as of December 31, 2000


            --  the going concern value per $1,000 limited partner investment

            --  the liquidation value per $1,000 limited partner investment


            --  the ordinary tax loss per $1,000 limited partner investment in
                year of initial investment


         o  Information about:

            --  the legal opinion for the limited partners

            --  the term of the partnership


         o  The partnership's quarterly report on Form 10-Q, including
            management's discussion and analysis of financial condition and
            results of operations, for the three months ended March 31, 2001

         o  The partnership's annual report on Form 10-K, including management's
            discussion and analysis of financial condition and results of
            operations, for the year ended December 31, 2000

         o  Selected historical financial data for the partnership for the three
            months ended March 31, 2001 and 2000 and the five years ended
            December 31, 2000

                                      -1-
   1167
                 PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.

                          SUPPLEMENTAL INFORMATION TABLE



                                                                                                
Aggregate Initial Investment by the Limited Partners  (a)                                          $   5,611

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                      $   6,928

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer          $   1,992
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                       $  357.55

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the
past four quarterly distributions including the distribution in July 2001  (b), (c)                     4.01 times

Book Value per $1,000 Limited Partner Investment:

        --  as of March 31, 2001  (c)                                                              $  255.48

        --  as of December 31, 2000  (c)                                                           $  263.74

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                                $  336.20

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                                  $  347.78

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment  (f)                --



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's oil and gas
     reserves and its net working capital, in each case as of March 31, 2001,
     less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on June , 2001, by the partnership to its partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Not applicable. Since this partnership purchased producing properties,
     there were no intangible drilling and development costs nor any related
     write-off for tax purposes.


           INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     Although not required by the partnership agreement for the partnership,
special legal counsel will render an opinion on behalf of the limited partners
to Pioneer USA that (1) neither the grant nor the exercise of the right to
approve the merger of the partnership by its limited partners will adversely
affect the federal income tax classification of the partnership or any of its
limited partners; and (2) neither the grant nor exercise of such right will
result in the loss of any limited partner's limited liability. In addition, the
counsel designated to render the opinion is not required to be counsel other
than counsel to Pioneer USA or the partnership. Both the designated counsel and
the legal opinion will be submitted for approval by the limited partners.
Pioneer USA has retained __________ of Dallas, Texas for the purpose of
rendering this legal opinion on behalf of the limited partners to Pioneer USA.
The merger proposals include an approval of that counsel and the form of its
opinion. A copy of the opinion is attached as an exhibit to the merger
proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   1168

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-19133-A


                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
             (Exact name of Registrant as specified in its charter)


                        Delaware                             75-2225758
            ----------------------------------         ---------------------
             (State or other jurisdiction of              (I.R.S. Employer
             incorporation or organization)            Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x] No [ ]






   1169



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.

                                TABLE OF CONTENTS





                                                                        Page
                                                                 
                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000.......................................   3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000............................   4

           Statement of Partners' Capital for the three months
             ended March 31, 2001.....................................   5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000............................   6

           Notes to Financial Statements..............................   7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations......................   7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K...........................   9

           Signatures.................................................  10



                                        2

   1170



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.       Financial Statements


                                 BALANCE SHEETS


                                                     March 31,        December 31,
                                                       2001               2000
                                                    -----------       -----------
                                                    (Unaudited)
                                                                
                 ASSETS

Current assets:
  Cash                                              $   238,408       $   253,499
  Accounts receivable - oil and gas sales               107,706           115,810
                                                    -----------       -----------
        Total current assets                            346,114           369,309
                                                    -----------       -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                4,855,712         4,855,712
Accumulated depletion                                (3,739,295)       (3,719,241)
                                                    -----------       -----------
        Net oil and gas properties                    1,116,417         1,136,471
                                                    -----------       -----------
                                                    $ 1,462,531       $ 1,505,780
                                                    ===========       ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $    14,629       $    11,054

Partners' capital:
  Managing general partner                               14,411            14,879
  Limited partners (11,222 interests)                 1,433,491         1,479,847
                                                    -----------       -----------
                                                      1,447,902         1,494,726
                                                    -----------       -----------
                                                    $ 1,462,531       $ 1,505,780
                                                    ===========       ===========



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   1171



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)






                                                            Three months ended
                                                                 March 31,
                                                          ---------------------
                                                            2001          2000
                                                          --------      --------
                                                                  
Revenues:
  Oil and gas                                             $195,445      $149,416
  Interest                                                   3,225         3,602
  Gain on disposition of assets                                 --         9,859
                                                          --------      --------
                                                           198,670       162,877
                                                          --------      --------
Costs and expenses:
  Oil and gas production                                    65,335        74,634
  General and administrative                                 5,863         4,482
  Depletion                                                 20,054        12,625
                                                          --------      --------
                                                            91,252        91,741
                                                          --------      --------
Net income                                                $107,418      $ 71,136
                                                          ========      ========
Allocation of net income:
  Managing general partner                                $  1,074      $    711
                                                          ========      ========
  Limited partners                                        $106,344      $ 70,425
                                                          ========      ========
Net income per limited partnership interest               $   9.48      $   6.28
                                                          ========      ========



         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   1172



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                 Managing
                                  general          Limited
                                  partner          partners            Total
                                -----------       -----------       -----------
                                                           
Balance at January 1, 2001      $    14,879       $ 1,479,847       $ 1,494,726

    Distributions                    (1,542)         (152,700)         (154,242)

    Net income                        1,074           106,344           107,418
                                -----------       -----------       -----------

Balance at March 31, 2001       $    14,411       $ 1,433,491       $ 1,447,902
                                ===========       ===========       ===========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   1173



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)







                                                          Three months ended
                                                               March 31,
                                                        -------------------------
                                                          2001             2000
                                                        ---------       ---------
                                                                  
Cash flows from operating activities:
  Net income                                            $ 107,418       $  71,136
  Adjustments to reconcile net income to net
    cash provided by operating activities:
      Depletion                                            20,054          12,625
      Gain on disposition of assets                            --          (9,859)
  Changes in assets and liabilities:
      Accounts receivable                                   8,104          21,426
      Accounts payable                                      3,575           3,590
                                                        ---------       ---------
         Net cash provided by operating activities        139,151          98,918
                                                        ---------       ---------
Cash flows provided by investing activities:
  Proceeds from disposition of assets                          --           9,859

Cash flows used in financing activities:
  Cash distributions to partners                         (154,242)       (124,431)
                                                        ---------       ---------
Net decrease in cash                                      (15,091)        (15,654)
Cash at beginning of period                               253,499         323,271
                                                        ---------       ---------
Cash at end of period                                   $ 238,408       $ 307,617
                                                        =========       =========



         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   1174



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley Producing Properties 88-A, L.P. (the "Partnership") is a
limited partnership organized in 1988 under the laws of the State of Delaware.

The Partnership engages in oil and gas production in Texas and is not involved
in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition and
            Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 31% to $195,445 for the three
months ended March 31, 2001 as compared to $149,416 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 4,417 barrels
of oil, 1,856 barrels of natural gas liquids ("NGLs") and 8,730 mcf of gas were
sold, or 7,728 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 3,708 barrels of oil, 2,352 barrels of NGLs and 9,789 mcf of gas
were sold, or 7,692 BOEs.

                                        7

   1175



The average price received per barrel of oil decreased $.58, or 2%, from $27.98
for the three months ended March 31, 2000 to $27.40 for the same period in 2001.
The average price received per barrel of NGLs increased $3.04, or 23%, from
$13.03 for the three months ended March 31, 2000 to $16.07 for the same period
in 2001. The average price received per mcf of gas increased 234% from $1.53
during the three months ended March 31, 2000 to $5.11 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $9,859 recognized during the three months ended
March 31, 2000 resulted from equipment credits received on one fully depleted
well.

Costs and Expenses:

Total costs and expenses decreased to $91,252 for the three months ended March
31, 2001 as compared to $91,741 for the same period in 2000, a decrease of $489.
This decrease was primarily due to a decline production costs, offset by
increases in depletion and general and administrative expenses ("G&A").

Production costs were $65,335 for the three months ended March 31, 2001 and
$74,634 for the same period in 2000 resulting in a $9,299 decrease, or 12%. This
decrease was primarily due to less well maintenance costs, offset by higher
production taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 31% from $4,482 for the three months ended March 31, 2000 to $5,863
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $20,054 for the three months ended March 31, 2001 as compared to
$12,625 for the same period in 2000, an increase of $7,429, or 59%. This
increase was primarily due to an increase in oil production of 709 barrels and
to a downward revision to proved reserves on one well for the period ended March
31, 2001 compared to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $40,233 for the three months
ended March 31, 2001 from the same period in 2000. The increase was primarily
attributable to an increase of $45,652 in oil and gas sales receipts and a
decline in production costs of $9,299, offset by increases in G&A expenses of
$1,381 and working capital of $13,337. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $39,603 to oil and gas receipts and $6,049 resulting from an increase
in production during 2001 as compared to the same period in 2000. The decrease
in production costs was primarily due to less well maintenance costs, offset by
an increase in production taxes associated with higher oil and gas prices and.
The increase in G&A was primarily due to an increase in the accrual for tax
preparation fees.

                                        8

   1176




Net Cash Provided by Investing Activities

Proceeds from asset dispositions of $9,859 recognized during the three months
ended March 31, 2000 resulted from equipment credits received on one fully
depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $154,242, of which $1,542 was distributed to the managing general partner
and $152,700 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $124,431, of which $1,244 was
distributed to the managing general partner and $123,187 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1) "Item 2. Management's Discussion and Analysis of Financial Condition and
    Results of Operations" contains forward looking statements that involve
    risks and uncertainties. Accordingly, no assurances can be given that the
    actual events and results will not be materially different than the
    anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)     Exhibits - none

(b)     Reports on Form 8-K - none

                                        9

   1177


                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                           PARKER & PARSLEY PRODUCING
                                           PROPERTIES 88-A, L.P.


                                  By:      Pioneer Natural Resources USA, Inc.
                                            Managing General Partner



Dated:  May 14, 2001              By:      /s/ Rich Dealy
                                           ----------------------------------
                                           Rich Dealy, Vice President
                                             and Chief Accounting Officer



                                       10

   1178
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-19133-A


                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
             (Exact name of Registrant as specified in its charter)

                   DELAWARE                                 75-2225758
        -------------------------------               ----------------------
        (State or other jurisdiction of                  (I.R.S. Employer
        incorporation or organization)                Identification Number)



                                                                               
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                      75039
----------------------------------------------------------------                  -------------
            (Address of principal executive offices)                               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                  LIMITED PARTNERSHIP INTERESTS ($500 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES /X/ NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. /X/

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$5,572,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 11,222.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.



   1179

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley Producing Properties 88-A, L.P. (the "Partnership") is a
limited partnership organized in 1988 under the laws of the State of Delaware.
The Partnership's managing general partner is Pioneer Natural Resources USA,
Inc. ("Pioneer USA"). Pioneer USA is a wholly-owned subsidiary of Pioneer
Natural Resources Company ("Pioneer"). As of March 8, 2001, the Partnership had
11,222 limited partnership interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 59% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial liability due to pollution and other
environmental damages. Although the Partnership believes that



                                       2
   1180

its business operations do not impair environmental quality and that its costs
of complying with any applicable environmental regulations are not currently
significant, the Partnership cannot predict what, if any, effect these
environmental regulations may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of working interests in properties on which
oil and gas wells are located. Such property interests are often subject to
landowner royalties, overriding royalties and other oil and gas leasehold
interests.

The Partnership completed one purchase of producing properties. This acquisition
involved the purchase of working interests in 21 properties, all of which are
operated by the managing general partner. In subsequent years, the Partnership
participated in the drilling of three additional wells and one well was plugged
and abandoned. At December 31, 2000 the Partnership had 23 producing oil and gas
properties.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                       3
   1181

                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
           DISTRIBUTIONS

At March 8, 2001, the Partnership had 11,222 outstanding limited partnership
interests held of record by 507 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $458,003 and $165,195, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                          2000            1999           1998            1997           1996
                                       -----------     ----------     -----------     ----------     ----------
                                                                                      
Operating results:
  Oil and gas sales                    $   742,384     $  495,753     $   443,496     $  753,775     $  938,418
                                       ===========     ==========     ===========     ==========     ==========

  Impairment of oil and gas
    properties                         $       -       $  280,950     $       -       $    6,231     $      -
                                       ===========     ==========     ===========     ==========     ==========

  Net income (loss)                    $   357,190     $ (111,304)    $   (13,621)    $  255,412     $  424,569
                                       ===========     ==========     ===========     ==========     ==========

  Allocation of net income (loss):
    Managing general partner           $     3,572     $   (1,113)    $      (136)    $    2,554     $    4,246
                                       ===========     ==========     ===========     ==========     ==========

    Limited partners                   $   353,618     $ (110,191)    $   (13,485)    $  252,858     $  420,323
                                       ===========     ==========     ===========     ==========     ==========

  Limited partners' net
    income (loss) per limited
    partnership interest               $     31.51     $    (9.82)    $     (1.20)    $    22.53     $    37.46
                                       ===========     ==========     ===========     ==========     ==========

  Limited partners' cash
    distributions per limited
    partnership interest               $     40.81     $    14.72     $     24.99     $    50.52     $    45.09
                                       ===========     ==========     ===========     ==========     ==========

At year end:
------------
  Identifiable assets                  $ 1,505,780     $1,613,628     $ 1,884,917     $2,212,937     $2,491,855
                                       ===========     ==========     ===========     ==========     ==========





                                       4
   1182


ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
           RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 50% to $742,384 for 2000 as
compared to $495,753 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 17,170
barrels of oil, 9,806 barrels of natural gas liquids ("NGLs") and 37,939 mcf of
gas were sold, or 33,299 barrel of oil equivalents ("BOEs"). In 1999, 19,878
barrels of oil, 10,402 barrels of NGLs and 44,467 mcf of gas were sold, or
37,691 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.62, or 75%, from
$16.82 for 1999 to $29.44 in 2000. The average price received per barrel of NGLs
increased $5.10, or 56%, from $9.18 for 1999 to $14.28 in 2000. The average
price received per mcf of gas increased 72%, from $1.48 for 1999 to $2.55 in
2000. The market price for oil and gas has been extremely volatile in the past
decade and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

A gain on disposition of assets of $9,859 was recognized during 2000 from
salvage income received on one fully depleted well.

Total costs and expenses decreased in 2000 to $411,959 as compared to $619,585
in 1999, a decrease of $207,626, or 34%. This decrease was primarily the result
of declines in the impairment of oil and gas properties and depletion, offset by
increases in production costs and general and administrative expenses ("G&A").

Production costs were $322,751 in 2000 and $237,875 in 1999, resulting in an
increase of $84,876, or 36%. The increase was primarily due to additional
workover expense and well maintenance costs incurred to stimulate well
production and higher production taxes associated with higher oil and gas
prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
50% from $14,872 in 1999 to $22,272 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $18,064 in 2000 and $8,371 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   1183

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $280,950 related to its oil and gas properties during 1999.

Depletion was $66,936 in 2000 as compared to $85,888 in 1999, representing a
decrease of $18,952, or 22%. This decrease was primarily due to a reduction in
the Partnership's net depletable basis from charges taken in accordance with
SFAS 121 during the fourth quarter of 1999 and a decline in oil production of
2,708 barrels for the period ended December 31, 2000 compared to the same period
in 1999, offset by a 20,203 barrels of oil decrease in proved reserves during
2000 as a result of a significant well having lower reserves due to a revised
decline curve.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 12% to $495,753 from
$443,496 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 19,878 barrels of oil,
10,402 barrels of NGLs and 44,467 mcf of gas were sold, or 37,691 BOEs. In 1998,
22,482 barrels of oil, 12,009 barrels of NGLs and 51,099 mcf of gas were sold,
or 43,008 BOEs.

The average price received per barrel of oil increased $3.68, or 28%, from
$13.14 for 1998 to $16.82 in 1999. The average price received per barrel of NGLs
increased $2.87, or 45%, from $6.31 for 1998 to $9.18 in 1999. The average price
received per mcf of gas increased 5%, from $1.41 for 1998 to $1.48 in 1999.

Total costs and expenses increased in 1999 to $619,585 as compared to $471,884
in 1998, an increase of $147,701, or 31%. This increase was primarily the result
of increases in the impairment of oil and gas properties and G&A expenses,
offset by declines in depletion and production costs.

Production costs were $237,875 in 1999 and $252,339 in 1998, resulting in a
$14,464, or 6%, decrease. The decrease was due to less well maintenance costs
and ad valorem taxes, offset by an increase in production taxes due to the
increase in oil and gas revenues.

During this period, G&A increased 12% from $13,305 in 1998 to $14,872 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $8,371 in
1999 and $9,891 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $280,950 related to its
oil and gas properties during 1999.

Depletion was $85,888 in 1999 compared to $206,240 in 1998. This represented a
decrease of $120,352, or 58%. This decrease was the result of an increase in
proved reserves of 77,231 barrels of oil during 1999 as a result of higher
commodity prices and a decline in oil production of 2,604



                                       6
   1184

barrels for the period ended December 31, 1999 compared to the same period in
1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $159,721 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $251,009 and a decline in working capital of $988,
offset by increases in production costs paid of $84,876 and G&A expenses paid of
$7,400. The increase in oil and gas receipts resulted from the increase in
commodity prices during 2000 which contributed an additional $355,912 to oil and
gas receipts, offset by $104,903 resulting from the decline in production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices and additional workover expenses
and well maintenance costs incurred to stimulate well production. The increase
in G&A was primarily due to higher percentage of the managing general partner's
G&A being allocated (limited to 3% of oil and gas revenues) as a result of
increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were
related to various upgrades of equipment.

Proceeds from asset dispositions of $9,859 recognized during 2000 were from
equipment credits received on one fully depleted well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $462,629, of which $4,626 was
distributed to the managing general partner and $458,003 to the limited
partners. In 1999, cash distributions to the partners were $166,787, of which
$1,592 was distributed to the managing general partner and $165,195 to the
limited partners.




                                       7
   1185


ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----
                                                                                      
Financial Statements of Parker & Parsley Producing Properties 88-A, L.P.:
 Independent Auditors' Report.........................................................     9
Balance Sheets as of December 31, 2000 and 1999.......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14



                                       8
   1186




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Producing Properties 88-A, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley Producing Properties
88-A, L.P. as of December 31, 2000 and 1999, and the related statements of
operations, partners' capital and cash flows for each of the three years in the
period ended December 31, 2000. These financial statements are the
responsibility of the Partnership's management. Our responsibility is to express
an opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Producing
Properties 88-A, L.P. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.




                                           Ernst & Young LLP

Dallas, Texas
March 9, 2001





                                       9
   1187



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31






                                                      2000              1999
                                                   -----------      -----------
                                                              
              ASSETS
              ------

Current assets:
  Cash                                             $   253,499      $   323,271
  Accounts receivable - oil and gas sales              115,810           87,732
                                                   -----------      -----------

       Total current assets                            369,309          411,003
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               4,855,712        4,854,930
Accumulated depletion                               (3,719,241)      (3,652,305)
                                                   -----------      -----------

       Net oil and gas properties                    1,136,471        1,202,625
                                                   -----------      -----------

                                                   $ 1,505,780      $ 1,613,628
                                                   ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                     $    11,054      $    13,463

Partners' capital:
  Managing general partner                              14,879           15,933
  Limited partners (11,222 interests)                1,479,847        1,584,232
                                                   -----------      -----------

                                                     1,494,726        1,600,165
                                                   -----------      -----------
                                                   $ 1,505,780      $ 1,613,628
                                                   ===========      ===========




   The accompanying notes are an integral part of these financial statements.



                                       10
   1188



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                           2000         1999           1998
                                                         --------     ---------      ---------

                                                                            
Revenues:
  Oil and gas                                            $742,384     $ 495,753      $ 443,496
  Interest                                                 16,906        12,528         14,767
  Gain on disposition of assets                             9,859           -              -
                                                         --------     ---------      ---------

                                                          769,149       508,281        458,263
                                                         --------     ---------      ---------

Costs and expenses:
  Oil and gas production                                  322,751       237,875        252,339
  General and administrative                               22,272        14,872         13,305
  Impairment of oil and gas properties                        -         280,950            -
  Depletion                                                66,936        85,888        206,240
                                                         --------     ---------      ---------

                                                          411,959       619,585        471,884
                                                         --------     ---------      ---------

Net income (loss)                                        $357,190     $(111,304)     $ (13,621)
                                                         ========     =========      =========

Allocation of net income (loss):
  Managing general partner                               $  3,572     $  (1,113)     $    (136)
                                                         ========     =========      =========

  Limited partners                                       $353,618     $(110,191)     $ (13,485)
                                                         ========     =========      =========

Net income (loss) per limited partnership interest       $  31.51     $   (9.82)     $   (1.20)
                                                         ========     =========      =========







   The accompanying notes are an integral part of these financial statements.



                                       11
   1189



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                           Managing
                                           general        Limited
                                           partner        partners           Total
                                           --------      -----------      -----------

                                                                 
Partners' capital at January 1, 1998       $ 21,564      $ 2,153,538      $ 2,175,102

   Distributions                             (2,790)        (280,435)        (283,225)

   Net loss                                    (136)         (13,485)         (13,621)
                                           --------      -----------      -----------

Partners' capital at December 31, 1998       18,638        1,859,618        1,878,256

   Distributions                             (1,592)        (165,195)        (166,787)

   Net loss                                  (1,113)        (110,191)        (111,304)
                                           --------      -----------      -----------

Partners' capital at December 31, 1999       15,933        1,584,232        1,600,165

   Distributions                             (4,626)        (458,003)        (462,629)

   Net income                                 3,572          353,618          357,190
                                           --------      -----------      -----------

Partners' capital at December 31, 2000     $ 14,879      $ 1,479,847      $ 1,494,726
                                           ========      ===========      ===========




   The accompanying notes are an integral part of these financial statements.



                                       12
   1190



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                          2000          1999           1998
                                                       ---------      ---------      ---------

                                                                            
Cash flows from operating activities:
  Net income (loss)                                    $ 357,190      $(111,304)     $ (13,621)
  Adjustments to reconcile net income (loss)
    to net cash provided  by operating activities:
      Impairment of oil and gas properties                   -          280,950            -
      Depletion                                           66,936         85,888        206,240
      Gain on disposition of assets                       (9,859)           -              -
    Changes in assets and liabilities:
      Accounts receivable                                (28,078)       (38,277)        69,159
      Accounts payable                                    (2,409)         6,802        (31,174)
                                                       ---------      ---------      ---------

        Net cash provided by operating activities        383,780        224,059        230,604
                                                       ---------      ---------      ---------

Cash flows from investing activities:
  Additions to oil and gas equipment                        (782)       (12,230)        (1,181)
  Proceeds from asset dispositions                         9,859            -              -
                                                       ---------      ---------      ---------

        Net cash provided by (used in)
          investing activities                             9,077        (12,230)        (1,181)
                                                       ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                        (462,629)      (166,787)      (283,225)
                                                       ---------      ---------      ---------

Net increase (decrease) in cash                          (69,772)        45,042        (53,802)
Cash at beginning of year                                323,271        278,229        332,031
                                                       ---------      ---------      ---------

Cash at end of year                                    $ 253,499      $ 323,271      $ 278,229
                                                       =========      =========      =========





   The accompanying notes are an integral part of these financial statements.



                                       13
   1191



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.
                        (A Delaware Limited Partnership)

                        NOTES TO FINANCIAL STATEMENTS
                       December 31, 2000, 1999 and 1998

NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley Producing Properties 88-A, L.P. (the "Partnership") is a
limited partnership organized in 1988 under the laws of the State of Delaware.
The Partnership's managing general partner is Pioneer Natural Resources USA,
Inc. ("Pioneer USA").

      The Partnership engages in oil and gas production in Texas and is not
involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.



                                       14
   1192

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $280,950 related to
its proved oil and gas properties during 1999.

NOTE 4.    INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $949,574 less than the tax basis at December 31, 2000.



                                       15
   1193

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                2000           1999           1998
                                                              ---------      ---------      --------

                                                                                   
Net income (loss) per statements of operations                $ 357,190      $(111,304)     $(13,621)
Depletion and depreciation provisions for tax
   reporting purposes less than (greater than)
   amounts for financial reporting purposes                     (55,096)        24,264        26,047
Impairment of oil and gas properties for financial
   reporting purposes                                               -          280,950           -
Other                                                              (247)          (441)          441
                                                              ---------      ---------      --------

Net income per Federal income tax
   returns                                                    $ 301,847      $ 193,469      $ 12,867
                                                              =========      =========      ========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999          1998
                                                    --------      --------      ---------

                                                                       
    Property acquisition costs                      $    782      $ 12,230      $   1,181
                                                    ========      ========      =========



      Capitalized oil and gas properties consist of the following:



                                       2000             1999
                                    -----------      -----------
                                               
Proved properties:
  Property acquisition costs        $ 4,109,672      $ 4,108,890
  Completed wells and equipment         746,040          746,040
                                    -----------      -----------

                                      4,855,712        4,854,930
Accumulated depletion                (3,719,241)      (3,652,305)
                                    -----------      -----------

  Net oil and gas properties        $ 1,136,471      $ 1,202,625
                                    ===========      ===========





                                       16
   1194



NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                         2000          1999          1998
                                                       ---------     ---------     ---------
                                                                          
      Payment of lease operating and supervision
        charges in accordance with standard
        industry operating agreements                  $  98,073     $  91,828     $  99,719

      Reimbursement of general and administrative
        expenses                                       $  18,064     $   8,371     $   9,891


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees Producing Properties 88-A ("EMPL") and the Partnership are parties
to the Program agreement. EMPL is a general partnership organized for the
benefit of certain employees of Pioneer USA. EMPL was merged with Pioneer USA on
December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnership as follows:



                                                               Pioneer USA (1)     Partnership
                                                               ---------------     -----------
                                                                             
  Revenues:
    Revenues from oil and gas production, proceeds from
      sales of producing properties and all other revenues:
        Before payout                                             4.040405%        95.959595%
        After payout (2)                                         19.191920%        80.808080%
  Costs and expenses:
    Property acquisition costs, operating costs, general and
      administrative expenses and other costs:
        Before payout                                             4.040405%        95.959595%
        After payout (2)                                         19.191920%        80.808080%


  (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level and 78 limited partner interests owned by
        Pioneer USA.

  (2)   The Partnership reached payout in September 1997.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                       17
   1195





                                            Oil and NGLs     Gas
                                               (bbls)        (mcf)
                                            ------------    --------

                                                      
Net proved reserves at January 1, 1998        563,684       808,875
Revisions                                    (105,464)      (18,612)
Production                                    (34,491)      (51,099)
                                             ---------      --------

Net proved reserves at December 31, 1998      423,729       739,164
Revisions                                     113,184       157,201
Production                                    (30,280)      (44,467)
                                             ---------      --------

Net proved reserves at December 31, 1999      506,633       851,898
Revisions                                     (52,176)     (249,428)
Production                                    (26,976)      (37,939)
                                             ---------      --------

Net proved reserves at December 31, 2000      427,481       564,531
                                             ========      ========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.90 per barrel of NGLs and $7.43 per mcf of gas,
discounted at 10% was approximately $3,258,000 and undiscounted was $6,795,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

      The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

      Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                       18
   1196


                                                                 For the years ended December 31,
                                                               ------------------------------------
                                                                 2000          1999         1998
                                                               --------      --------      -------
                                                                          (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                          $ 13,506      $ 12,421      $ 4,629
  Future production costs                                        (6,711)       (5,947)      (3,105)
                                                               --------      --------      -------

                                                                  6,795         6,474        1,524
  10% annual discount factor                                     (3,537)       (3,486)        (609)
                                                               --------      --------      -------

  Standardized measure of discounted future net cash flows     $  3,258      $  2,988      $   915
                                                               ========      ========      =======


                                                                For the years ended December 31,
                                                               -----------------------------------
                                                                 2000          1999         1998
                                                                -------      -------      -------
                                                                          (in thousands)
                                                                                 
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs                    $  (420)     $  (258)     $  (191)
  Net changes in prices and production costs                        906        2,308       (1,425)
  Revisions of previous quantity estimates                         (564)         836         (152)
  Accretion of discount                                             299           92          244
  Changes in production rates, timing and other                      49         (905)          (5)
                                                                -------      -------      -------

  Change in present value of future net revenues                    270        2,073       (1,529)
                                                                -------      -------      -------

  Balance, beginning of year                                      2,988          915        2,444
                                                                -------      -------      -------

  Balance, end of year                                          $ 3,258      $ 2,988      $   915
                                                                =======      =======      =======


NOTE 8.    MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
           Plains Marketing, L.P.                     59%            57%            -
           Western Gas Resources, Inc.                 4%             6%           28%
           Genesis Crude Oil, L.P.                     -              -            57%


      At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $44,879 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Partnership affairs. As managing general partner and
      operator of the Partnership's properties, all production expenses are
      incurred by Pioneer USA and billed to the Partnership. The majority of the
      Partnership's oil and gas revenues are received directly by the
      Partnership, however, a portion of the oil and gas revenue is initially
      received by Pioneer USA prior to being paid to the Partnership. Under the
      limited partnership agreement, the managing general partner pays 1% of the
      Partnership's acquisition, drilling and completion costs and 1% of its
      operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total



                                       19
   1197

      contributions of such partner plus his share of any undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of $5,611,000.
      Pioneer USA is required to contribute amounts equal to 1% of initial
      Partnership capital less commission and offering expenses allocated to the
      limited partners and to contribute amounts necessary to pay costs and
      expenses allocated to it under the Partnership agreement to the extent its
      share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
           AND FINANCIAL DISCLOSURE

None.





                                       20
   1198



                                    PART III

ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Directors

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   1199



      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   1200



ITEM 11.    EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the limited
partnership agreement, Pioneer USA pays 1% of the Program's acquisition,
drilling and completion costs and 1% of its operating, general and
administrative expenses. In return, Pioneer USA is allocated 1% of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)   Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 78 limited partner interests at January 1, 2001.

(b)   Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                       23
   1201



                                                        2000           1999          1998
                                                      ---------      ---------     ---------
                                                                          
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                   $  98,073      $  91,828     $  99,719

    Reimbursement of general and administrative
      expenses                                        $  18,064      $   8,371     $   9,891


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.



                                       24
   1202



                                     PART IV

ITEM 14.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                 Statements of partners' capital for the years ended December
                   31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31,
                   2000, 1999 and 1998

                 Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   1203



                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                           PARKER & PARSLEY PRODUCING
                              PROPERTIES 88-A, L.P.

Dated: March 26, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                --------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 26, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 26, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 26, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 26, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 26, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 26, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       26
   1204



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.

                                INDEX TO EXHIBITS



      The following documents are incorporated by reference in response to Item
14(c):



    Exhibit No.                             Description                           Page
    -----------                             -----------                           ----

                                                                            
       3(a)               Agreement of Limited Partnership of                       -
                          Parker & Parsley Producing Properties
                          88-A, L.P. incorporated by reference to
                          Exhibit A of Amendment No. 1 of the
                          Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-19133)
                          (hereinafter referred to as the Partnership's
                          Registration Statement)

       4(b)               Subscription Agreement and Power of                       -
                          Attorney incorporated by reference to
                          Exhibit C of the Partnership's Registration
                          Statement

       4(d)               Form of Certificate of Limited Partnership                -
                          Interest incorporated by reference to Exhibit
                          4d of the Partnership's Registration
                          Statement

      10(b)               Program Agreement incorporated by reference               -
                          to Exhibit B of the Partnership's Registration
                          Statement





                                       27
   1205



                PARKER & PARSLEY PRODUCING PROPERTIES 88-A, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  149,416   $  742,384   $  495,753   $  443,496   $  753,775   $  938,418
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $  280,950   $       --   $    6,231   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   71,136   $  357,190   $ (111,304)  $  (13,621)  $  255,412   $  424,569
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
      Managing general
        partner                    $          $      711   $    3,572   $   (1,113)  $     (136)  $    2,554   $    4,246
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $   70,425   $  353,618   $ (110,191)  $  (13,485)  $  252,858   $  420,323
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $     6.28   $    31.51   $    (9.82)  $    (1.20)  $    22.53   $    37.46
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    10.98   $    40.81   $    14.72   $    24.99   $    50.52   $    45.09
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,563,923   $1,505,780   $1,613,628   $1,884,917   $2,212,937   $2,491,855
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1206

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

            PROXY STATEMENT/PROSPECTUS DATED           , 2001

                                   ----------

             THE DATE OF THIS SUPPLEMENT IS           , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Private Investment 88, L.P., and supplements the proxy statement/prospectus
dated           , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Private Investment 88, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   1207


                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                          
Aggregate Initial Investment by the Limited Partners(a)                                                      $      9,960

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                                  $     11,812

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)        $      3,421

Merger Value per $1,000 Limited Partner Investment(b), (c)                                                   $     343.50

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                                3.88 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                          $     155.75

      --    as of December 31, 2000(c)                                                                       $     160.08

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                            $     321.84

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                              $     333.37

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)                $        152



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2038, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   1208

                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   1209



                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS





                                                      March 31,         December 31,
                                                        2001                2000
                                                     -----------        -----------
                                                     (Unaudited)

                                                                  
                 ASSETS

Current assets:
  Cash                                               $   169,783        $   174,638
  Accounts receivable - oil and gas sales                178,170            190,189
                                                     -----------        -----------
        Total current assets                             347,953            364,827
                                                     -----------        -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                 7,350,673          7,348,142
Accumulated depletion                                 (6,111,934)        (6,092,889)
                                                     -----------        -----------
        Net oil and gas properties                     1,238,739          1,255,253
                                                     -----------        -----------
                                                     $ 1,586,692        $ 1,620,080
                                                     ===========        ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $    19,592        $     9,440

Partners' capital:
  Managing general partner                                15,835             16,271
  Limited partners (249 interests)                     1,551,265          1,594,369
                                                     -----------        -----------
                                                       1,567,100          1,610,640
                                                     -----------        -----------
                                                     $ 1,586,692        $ 1,620,080
                                                     ===========        ===========




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        2

   1210



                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                      Three months ended
                                                          March 31,
                                                  ---------------------------
                                                     2001             2000
                                                  ----------       ----------
                                                             
Revenues:
  Oil and gas                                     $  339,232       $  274,206
  Interest                                             2,839            2,593
                                                  ----------       ----------
                                                     342,071          276,799
                                                  ----------       ----------
Costs and expenses:
  Oil and gas production                             121,120          110,748
  General and administrative                           8,481            8,226
  Depletion                                           19,045           20,937
                                                  ----------       ----------
                                                     148,646          139,911
                                                  ----------       ----------
Net income                                        $  193,425       $  136,888
                                                  ==========       ==========
Allocation of net income:
  Managing general partner                        $    1,934       $    1,369
                                                  ==========       ==========
  Limited partners                                $  191,491       $  135,519
                                                  ==========       ==========
Net income per limited partnership interest       $   769.04       $   544.25
                                                  ==========       ==========




       The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.


                                        3

   1211



                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                   Managing
                                   general            Limited
                                   partner            partners            Total
                                 -----------        -----------        -----------


                                                              
Balance at January 1, 2001       $    16,271        $ 1,594,369        $ 1,610,640

    Distributions                     (2,370)          (234,595)          (236,965)

    Net income                         1,934            191,491            193,425
                                 -----------        -----------        -----------

Balance at March 31, 2001        $    15,835        $ 1,551,265        $ 1,567,100
                                 ===========        ===========        ===========






         The financial information included herein has been prepared by
           management without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        4

   1212



                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                             Three months ended
                                                                  March 31,
                                                         ----------------------------
                                                            2001              2000
                                                         ----------        ----------
                                                                     
Cash flows from operating activities:
  Net income                                             $  193,425        $  136,888
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                             19,045            20,937
  Changes in assets and liabilities:
       Accounts receivable                                   12,019             2,189
       Accounts payable                                      10,152             5,352
                                                         ----------        ----------
         Net cash provided by operating activities          234,641           165,366
                                                         ----------        ----------
Cash flows from investing activities:
  Additions to oil and gas properties                        (2,531)           (4,968)
  Proceeds from disposition of assets                            --               467
                                                         ----------        ----------
         Net cash used in investing activities               (2,531)           (4,501)
                                                         ----------        ----------
Cash flows used in financing activities:
  Cash distributions to partners                           (236,965)         (160,897)
                                                         ----------        ----------
Net decrease in cash                                         (4,855)              (32)
Cash at beginning of period                                 174,638           200,529
                                                         ----------        ----------
Cash at end of period                                    $  169,783        $  200,497
                                                         ==========        ==========



         The financial information included herein has been prepared by the
  managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        5

   1213

                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley Private Investment 88, L.P. (the "Partnership") was organized
in 1988 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1989.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and Results of
   Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 24% to $339,232 for the three
months ended March 31, 2001 as compared to $274,206 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 7,599
barrels of oil, 2,038 barrels of natural gas liquids ("NGLs") and 14,638 mcf of
gas were sold, or 12,077 barrel of oil equivalents ("BOEs"). For the three

                                        6

   1214



months ended March 31, 2000, 7,128 barrels of oil, 3,764 barrels of NGLs and
15,649 mcf of gas were sold, or 13,500 BOEs.

The average price received per barrel of oil increased $.71, or 3%, from $27.22
for the three months ended March 31, 2000 to $27.93 for the same period in 2001.
The average price received per barrel of NGLs increased $4.83, or 34%, from
$14.02 for the three months ended March 31, 2000 to $18.85 for the same period
in 2001. The average price received per mcf of gas increased 246% from $1.75
during the three months ended March 31, 2000 to $6.05 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $148,646 for the three months ended March
31, 2001 as compared to $139,911 for the same period in 2000, an increase of
$8,735, or 6%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $121,120 for the three months ended March 31, 2001 and
$110,748 for the same period in 2000 resulting in a $10,372 increase, or 9%. The
increase was primarily due to additional well maintenance costs incurred to
stimulate well production and higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 3% from $8,226 for the three months ended March 31, 2000 to $8,481 for
the same period in 2001, primarily due to an increase in the accrual for tax
preparation fees.

Depletion was $19,045 for the three months ended March 31, 2001 compared to
$20,937 for the same period in 2000, a decrease of $1,892, or 9%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $69,275 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $65,272 and a
reduction in working capital of $14,630, offset by increases in production costs
of $10,372 and G&A expenses of $255. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $90,763 to oil and gas receipts, offset by $25,491 resulting from the

                                        7

   1215


decline in production during 2001 as compared to 2000. The increase in
production costs was primarily due to additional well maintenance costs incurred
to stimulate well production and increased production taxes associated with
higher oil and gas prices. The increase in G&A was primarily due to an increase
in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from disposition of assets of $467 recognized during the three months
ended March 31, 2000 were due to equipment credits received on one active well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $236,965, of which $2,370 was distributed to the managing general partner
and $234,595 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $160,897, of which $1,609 was
distributed to the managing general partner and $159,288 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.

                                        8



   1216
                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   1217




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Private Investment 88, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley Private Investment 88,
L.P. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Private
Investment 88, L.P. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                        2
   1218


                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                    2000            1999
                                                    ----            ----
             ASSETS
             ------
                                                          
Current assets:
 Cash                                            $   174,638    $   200,529
 Accounts receivable - oil and gas sales             190,189        115,936
                                                 -----------    -----------

        Total current assets                         364,827        316,465
                                                 -----------    -----------

Oil and gas properties - at cost, based on the
 successful efforts accounting method              7,348,142      7,339,803
Accumulated depletion                             (6,092,889)    (6,015,639)
                                                 -----------    -----------

        Net oil and gas properties                 1,255,253      1,324,164
                                                 -----------    -----------

                                                 $ 1,620,080    $ 1,640,629
                                                 ===========    ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
 Accounts payable - affiliate                    $     9,440    $    16,379

Partners' capital:
 Managing general partner                             16,271         16,407
 Limited partners (249 interests)                  1,594,369      1,607,843
                                                 -----------    -----------

                                                   1,610,640      1,624,250
                                                 -----------    -----------
                                                 $ 1,620,080    $ 1,640,629
                                                 ===========    ===========










   The accompanying notes are an integral part of these financial statements.



                                        3
   1219


                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                        For the years ended December 31






                                                        2000         1999         1998
                                                     ----------   ----------   ----------
                                                                      
Revenues:
  Oil and gas                                        $1,311,024   $  805,538   $  645,636
  Interest                                               14,327        8,390        9,025
  Gain on disposition of assets                              --           --          237
                                                     ----------   ----------   ----------

                                                      1,325,351      813,928      654,898
                                                     ----------   ----------   ----------

Costs and expenses:
  Oil and gas production                                425,425      361,694      390,754
  General and administrative                             33,284       24,166       17,997
  Impairment of oil and gas properties                       --           --      118,049
  Depletion                                              77,250      140,915      327,453
                                                     ----------   ----------   ----------

                                                        535,959      526,775      854,253
                                                     ----------   ----------   ----------

Net income (loss)                                    $  789,392   $  287,153   $ (199,355)
                                                     ==========   ==========   ==========

Allocation of net income (loss):
  Managing general partner                           $    7,894   $    2,872   $   (1,994)
                                                     ==========   ==========   ==========

  Limited partners                                   $  781,498   $  284,281   $ (197,361)
                                                     ==========   ==========   ==========

Net income (loss) per limited partnership interest   $ 3,138.55   $ 1,141.69   $  (792.61)
                                                     ==========   ==========   ==========




















   The accompanying notes are an integral part of these financial statements.



                                        4
   1220



                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                     Managing
                                                      general       Limited
                                                      partner       partners       Total
                                                     ---------      --------     --------
                                                                      
Partners' capital at January 1, 1998               $ 21,549      $2,116,932    $2,138,481

    Distributions                                    (2,892)       (286,347)     (289,239)

    Net loss                                         (1,994)       (197,361)     (199,355)
                                                     ------        --------      --------

Partners' capital at December 31, 1998               16,663       1,633,224     1,649,887

    Distributions                                    (3,128)       (309,662)     (312,790)

    Net income                                        2,872         284,281       287,153
                                                     ------        --------       -------

Partners' capital at December 31, 1999               16,407       1,607,843     1,624,250

    Distributions                                    (8,030)       (794,972)     (803,002)

    Net income                                        7,894         781,498       789,392
                                                     ------        --------       -------

Partners' capital at December 31, 2000             $ 16,271      $1,594,369    $1,610,640
                                                    =======       =========     =========





















   The accompanying notes are an integral part of these financial statements.




                                        5
   1221

                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                       2000         1999         1998
                                                     ---------    ---------    ---------

                                                                      
Cash flows from operating activities:
   Net income (loss)                                 $ 789,392    $ 287,153    $(199,355)
   Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
       Impairment of oil and gas properties                 --           --      118,049
       Depletion                                        77,250      140,915      327,453
       Gain on disposition of assets                        --           --         (237)
   Changes in assets and liabilities:
       Accounts receivable                             (74,253)     (50,145)      43,119
       Accounts payable                                 (6,939)       4,823       (9,123)
                                                     ---------    ---------    ---------

         Net cash provided by operating activities     785,450      382,746      279,906
                                                     ---------    ---------    ---------

Cash flows from investing activities:
   Additions to oil and gas properties                  (8,806)      (9,360)     (14,794)
   Proceeds from disposition of assets                     467           --          237
                                                     ---------    ---------    ---------

         Net cash used in investing activities          (8,339)      (9,360)     (14,557)
                                                     ---------    ---------    ---------

Cash flows used in financing activities:
   Cash distributions to partners                     (803,002)    (312,790)    (289,239)
                                                     ---------    ---------    ---------

Net increase (decrease) in cash                        (25,891)      60,596      (23,890)
Cash at beginning of year                              200,529      139,933      163,823
                                                     ---------    ---------    ---------

Cash at end of year                                  $ 174,638    $ 200,529    $ 139,933
                                                     =========    =========    =========
















   The accompanying notes are an integral part of these financial statements.



                                       6
   1222



                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.        ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley Private Investment 88, L.P. (the "Partnership") was
organized in 1988 as a general partnership under the laws of the State of Texas
and was converted to a Delaware limited partnership in 1989. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.        SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.




                                       7
   1223
        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentation.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.       IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the



                                       8
   1224

Partnership recognized a non-cash impairment provision of $118,049 related to
its proved oil and gas properties during 1998.

NOTE 4.        INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $148,226 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                   2000          1999           1998
                                                                ---------     ---------        -------
                                                                                    
    Net income (loss) per statements of operations              $ 789,392     $ 287,153      $(199,355)
    Depletion and depreciation provisions for tax reporting
      purposes less than amounts for financial reporting
      purposes                                                     67,335       130,790        319,019
    Impairment of oil and gas properties for financial
      reporting purposes                                               -             -         118,049
    Other, net                                                     (1,469)          221             78
                                                                ---------     ---------        -------

           Net income per Federal income tax returns            $ 855,258     $ 418,164      $ 237,791
                                                                =========     =========      =========



NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                    ---------     ---------      -------
                                                                       
      Development costs                            $   8,806     $   9,360      $  14,794
                                                    ========      ========       ========


      Capitalized oil and gas properties consist of the following:



                                                                      2000           1999
                                                                      ----           ----
                                                                         
      Proved properties:
        Property acquisition costs                               $    76,042    $    76,042
        Completed wells and equipment                              7,272,100      7,263,761
                                                                   ---------      ---------

                                                                   7,348,142      7,339,803
      Accumulated depletion                                       (6,092,889)    (6,015,639)
                                                                  -----------    ----------

           Net oil and gas properties                            $ 1,255,253    $ 1,324,164
                                                                  ==========     ==========




                                       9
   1225



NOTE 6.       RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                                                              2000       1999      1998
                                                                                            --------   --------   -----
                                                                                                      
    Payment of lease operating and supervision
      charges in accordance with standard industry
      operating agreements                                                              $  164,648  $ 159,072  $ 153,460

    Reimbursement of general and administrative expenses                                $   29,882  $  18,547  $  14,864


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and the Partnership are parties to the Program agreement.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                             Pioneer USA (1)   Partnership
                                                             ---------------   -----------
                                                                         
     Revenues:
       Proceeds from disposition of depreciable
         properties                                             9.09091%        90.90909%
       All other revenues                                      24.242425%       75.757575%
     Costs and expenses:
       Lease acquisition costs, drilling and completion
         costs and all other costs                              9.09091%        90.90909%
       Operating costs, direct costs and general and
         administrative expenses                               24.242425%       75.757575%


       (1) Excludes Pioneer USA's 1% general partner ownership which is
allocated at the Partnership level.

NOTE 7.       OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.






                                       10
   1226



                                         Oil and NGLs      Gas
                                             (bbls)        (mcf)
                                           ----------    ----------
                                                   
Net proved reserves at January 1, 1998        642,625       841,260
Revisions                                    (223,184)     (203,072)
Production                                    (48,933)      (61,718)
                                           ----------    ----------

Net proved reserves at December 31, 1998      370,508       576,470
Revisions                                     353,229       566,412
Production                                    (48,802)      (66,701)
                                           ----------    ----------


Net proved reserves at December 31, 1999      674,935     1,076,181
Revisions                                     142,138       (79,131)
Production                                    (46,284)      (59,532)
                                           ----------    ----------

Net proved reserves at December 31, 2000      770,789       937,518
                                           ==========    ==========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.25 per barrel of NGLs and $7.86 per mcf of gas,
discounted at 10% was approximately $5,885,000 and undiscounted was $12,796,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                              For the years ended December 31,
                                                           -----------------------------------
                                                              2000        1999       1998
                                                             --------    --------    --------
                                                                    (in thousands)
                                                                           
Oil and gas producing activities:
  Future cash inflows                                       $ 24,468    $ 16,797    $  4,079
  Future production costs                                    (11,672)     (9,146)     (2,814)
                                                            --------    --------    --------
                                                              12,796       7,651       1,265
  10% annual discount factor                                  (6,911)     (3,791)       (504)
                                                            --------    --------    --------
 Standardized measure of discounted future net cash flows   $  5,885    $  3,860    $    761
                                                            ========    ========    ========





                                       11
   1227




                                                          For the years ended December 31,
                                                       ---------------------------------------
                                                          2000            1999        1998
                                                         --------     ---------     --------
                                                                     (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (886)  $      (444)  $     (255)
    Net changes in prices and production costs              2,139         1,723       (1,538)
    Revisions of previous quantity estimates                  898         2,410         (366)
    Accretion of discount                                     386            76          273
    Changes in production rates, timing and other            (512)         (666)         (79)
                                                         --------     ---------     --------

    Change in present value of future net revenues          2,025         3,099       (1,965)
                                                         --------     ---------     --------

    Balance, beginning of year                              3,860           761        2,726
                                                         --------     ---------     --------

    Balance, end of year                               $    5,885   $     3,860   $      761
                                                        =========    ==========    =========


NOTE 8.        MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                          2000        1999          1998
                                                        --------    --------      --------
                                                                         
              Plains Marketing, L.P.                       55%          52%            -
              Genesis Crude Oil, L.P.                       -            -            63%
              Western Gas Resources, Inc.                   4%           5%           21%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $52,075 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.        PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. The managing general partner is also responsible for




                                       12
   1228
        1% of the guaranty and loan commitment fees. In return, it is allocated
        1% of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $9,960,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.


                                       13
   1229

                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
    RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 63% to $1,311,024 for 2000 as
compared to $805,538 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 30,403
barrels of oil, 15,881 barrels of natural gas liquids ("NGLs") and 59,532 mcf of
gas were sold, or 56,206 barrel of oil equivalents ("BOEs"). In 1999, 30,947
barrels of oil, 17,855 barrels of NGLs and 66,701 mcf of gas were sold, or
59,919 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.44, or 73%, from
$17.01 in 1999 to $29.45 in 2000. The average price received per barrel of NGLs
increased $6.29, or 67%, from $9.32 in 1999 to $15.61 in 2000. The average price
received per mcf of gas increased 67% from $1.69 in 1999 to $2.82 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $535,959 as compared to $526,775
in 1999, an increase of $9,184, or 2%. The increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $425,425 in 2000 and $361,694 in 1999, resulting in a
$63,731 increase, or 18%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
38% from $24,166 in 1999 to $33,284 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $29,882 in 2000 and $18,547 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $77,250 in 2000 compared to $140,915 in 1999, representing a
decrease of $63,665, or 45%. This decrease was primarily due to a 111,058
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 25% to $805,538 from
$645,636 in 1998. The increase in revenues resulted from higher average prices
received. In 1999, 30,947 barrels of oil, 17,855 barrels of NGLs and 66,701 mcf
of gas



   1230

were sold, or 59,919 BOEs. In 1998, 33,377 barrels of oil, 15,556 barrels of
NGLs and 61,718 mcf of gas were sold, or 59,219 BOEs.

The average price received per barrel of oil increased $3.70, or 28%, from
$13.31 in 1998 to $17.01 in 1999. The average price received per barrel of NGLs
increased $2.53, or 37%, from $6.79 in 1998 to $9.32 in 1999. The average price
received per mcf of gas increased 9% from $1.55 in 1998 to $1.69 in 1999.

Total costs and expenses decreased in 1999 to $526,775 as compared to $854,253
in 1998, a decrease of $327,478, or 38%. The decrease was due to declines in
depletion, the impairment of oil and gas properties and production costs, offset
by an increase in G&A.

Production costs were $361,694 in 1999 and $390,754 in 1998, resulting in a
$29,060 decrease, or 7%. The decrease was due to declines in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes due to
increased oil and gas revenues.

During this period, G&A increased 34% from $17,997 in 1998 to $24,166 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $18,547 in
1999 and $14,864 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $118,049 related to its oil and gas properties during 1998.

Depletion was $140,915 in 1999 compared to $327,453 in 1998, representing a
decrease of $186,538, or 57%. This decrease was the result of an increase in
proved reserves of 220,875 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.







   1231


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $402,704 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $511,423, offset by increases in production costs paid
of $63,731, G&A expenses paid of $9,118 and working capital of $35,870. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $578,466 to oil and gas receipts,
offset by $67,043 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs
incurred to stimulate well production. The increase in G&A was primarily due to
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Proceeds recognized during 2000 of $467 were due to equipment credits received
on an active property.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $803,002, of which $8,030 was
distributed to the managing general partner and $794,972 to the limited
partners. In 1999, cash distributions to the partners were $312,790, of which
$3,128 was distributed to the managing general partner and $309,662 to the
limited partners.












   1232





                  PARKER & PARSLEY PRIVATE INVESTMENT 88, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  274,206   $1,311,024   $  805,538   $  645,636   $  940,268   $1,151,975
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  118,049   $  791,857   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  136,888   $  789,392   $  287,153   $ (199,355)  $ (485,703)  $  480,356
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $    1,369   $    7,894   $    2,872   $   (1,994)  $   (4,857)  $    4,804
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  135,519   $  781,498   $  284,281   $ (197,361)  $ (480,846)  $  475,552
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   544.25   $ 3,138.55   $ 1,141.69   $  (792.61)  $(1,931.11)  $ 1,909.85
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   639.71   $ 3,192.66   $ 1,243.62   $ 1,149.99   $ 2,376.82   $ 2,312.00
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $1,621,972   $1,620,080   $1,640,629   $1,661,443   $2,159,160   $3,237,747
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1233
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 89-A CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ---------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ---------


     This document contains important information specific to Parker & Parsley
89-A Conv., L.P., and supplements the proxy statement/prospectus dated       ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 89-A Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1234
                        PARKER & PARSLEY 89-A CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                     
Aggregate Initial Investment by the Limited Partners(a)                                 $ 2,797

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)             $ 2,993

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding       $   923
Pioneer USA(a),(b)

Merger Value per $1,000 Limited Partner Investment(b),(c)                               $329.99

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for      3.50 times
the past four quarterly distributions including the distribution in July 2001(b),(c)

Book Value per $1,000 Limited Partner Investment:

        --   as of March 31, 2001(c)                                                    $153.81

        --   as of December 31, 2000(c)                                                 $158.81

Going Concern Value per $1,000 Limited Partner Investment(c),(d)                        $308.46

Liquidation Value per $1,000 Limited Partner Investment(c),(e)                          $320.29

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment   $   149
(c),(f)



---------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   1235

                        PARKER & PARSLEY 89-A CONV., L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001

   1236

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS



                                                      March 31,     December 31,
                                                        2001            2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS

                                                              
Current assets:
  Cash                                              $    43,887     $    49,781
  Accounts receivable - oil and gas sales                55,614          57,620
                                                    -----------     -----------
        Total current assets                             99,501         107,401
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                2,150,768       2,205,981
Accumulated depletion                                (1,811,228)     (1,860,437)
                                                    -----------     -----------
        Net oil and gas properties                      339,540         345,544
                                                    -----------     -----------
                                                    $   439,041     $   452,945
                                                    ===========     ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $     4,426     $     4,194

Partners' capital:
  Managing general partner                                4,415           4,556
  Limited partners (2,797 interests)                    430,200         444,195
                                                    -----------     -----------
                                                        434,615         448,751
                                                    -----------     -----------
                                                    $   439,041     $   452,945
                                                    ===========     ===========


  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        2

   1237

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                         Three months ended
                                                              March 31,
                                                     --------------------------
                                                        2001            2000
                                                     ----------      ----------
                                                               
Revenues:
  Oil and gas                                        $  110,224      $   81,009
  Interest                                                  884             770
  Gain on disposition of assets                           3,713              --
                                                     ----------      ----------
                                                        114,821          81,779
                                                     ----------      ----------
Costs and expenses:
  Oil and gas production                                 33,385          31,408
  General and administrative                              3,912           2,441
  Depletion                                               6,004           6,327
  Abandoned property                                      2,335              --
                                                     ----------      ----------
                                                         45,636          40,176
                                                     ----------      ----------
Net income                                           $   69,185      $   41,603
                                                     ==========      ==========
Allocation of net income:
  Managing general partner                           $      692      $      416
                                                     ==========      ==========
  Limited partners                                   $   68,493      $   41,187
                                                     ==========      ==========
Net income per limited partnership interest          $    24.49      $    14.73
                                                     ==========      ==========


       The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   1238

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)



                                       Managing
                                       general        Limited
                                       partner        partners         Total
                                      ----------     ----------     ----------


                                                           
Balance at January 1, 2001            $    4,556     $  444,195     $  448,751

    Distributions                           (833)       (82,488)       (83,321)

    Net income                               692         68,493         69,185
                                      ----------     ----------     ----------

Balance at March 31, 2001             $    4,415     $  430,200     $  434,615
                                      ==========     ==========     ==========


       The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        4

   1239

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                           Three months ended
                                                               March 31,
                                                        -----------------------
                                                           2001         2000
                                                        ---------     ---------

                                                                
Cash flows from operating activities:
  Net income                                            $  69,185     $  41,603
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            6,004         6,327
       Gain on disposition of assets                       (3,713)           --
  Changes in assets and liabilities:
       Accounts receivable                                  2,006        (1,277)
       Accounts payable                                     3,945           647
                                                        ---------     ---------
           Net cash provided by operating activities       77,427        47,300
                                                        ---------     ---------
Cash flows used in investing activities:
  Additions to oil and gas properties                          --          (469)

Cash flows used in financing activities:
  Cash distributions to partners                          (83,321)      (50,740)
                                                        ---------     ---------
Net decrease in cash                                       (5,894)       (3,909)
Cash at beginning of period                                49,781        58,311
                                                        ---------     ---------
Cash at end of period                                   $  43,887     $  54,402
                                                        =========     =========


       The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        5

   1240

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 89-A Conv., L.P. (the "Partnership") was organized in 1989 as a
general partnership under the laws of the State of Texas and was converted to a
Delaware limited partnership in 1990.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 36% to $110,224 for the three
months ended March 31, 2001 as compared to $81,009 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 2,177 barrels
of oil, 839 barrels of natural gas liquids ("NGLs") and 5,605 mcf of gas were
sold, or 3,950 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 2,078 barrels of oil, 1,072 barrels of NGLs and 4,757 mcf of gas
were sold, or 3,943 BOEs.

The average price received per barrel of oil increased $.62, or 2%, from $27.48
for the three months ended March 31, 2000 to $28.10 for the same period in 2001.
The average price received per barrel of NGLs increased $3.52, or 25%, from

                                        6

   1241

$13.84 for the three months ended March 31, 2000 to $17.36 for the same period
in 2001. The average price received per mcf of gas increased 223% from $1.91
during the three months ended March 31, 2000 to $6.16 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $3,713 was recognized during the three months
ended March 31, 2001 from equipment salvage received on one well plugged and
abandoned during the current period. Abandoned property costs of $2,335 were
incurred to plug and abandon this well.

Costs and Expenses:

Total costs and expenses increased to $45,636 for the three months ended March
31, 2001 as compared to $40,176 for the same period in 2000, an increase of
$5,460, or 14%. This increase was due to increases in abandoned property costs,
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $33,385 for the three months ended March 31, 2001 and
$31,408 for the same period in 2000 resulting in a $1,977 increase, or 6%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 60% from $2,441 for the three months ended March 31, 2000 to $3,912
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $6,004 for the three months ended March 31, 2001 compared to
$6,327 for the same period in 2000, a decrease of $323, or 5%. This decrease was
primarily due to downward revisions to proved reserves on several wells during
the three months ended March 31, 2001, offset by an increase in oil production
of 99 barrels for the period ended March 31, 2001 compared to the same period in
2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $30,127 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $29,329 and a
reduction in working capital of $6,581, offset by increases in production costs
of $1,977, G&A expenses of $1,471 and abandoned property costs of $2,335. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2001 which contributed an additional $25,364 to oil and gas receipts and
$3,965 resulting from the increase in production during 2001 as compared to the

                                        7

   1242

same period in 2000. The increase in production costs was primarily due to
increased production taxes associated with higher oil and gas prices. The
increase in G&A was primarily due to a higher percentage of the managing general
partner's G&A being allocated (limited to 3% of oil and gas revenues) as a
result of increased oil and gas revenues and an increase in the accrual for tax
preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $83,321, of which $833 was distributed to the managing general partner and
$82,488 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $50,740, of which $507 was distributed to the
managing general partner and $50,233 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.

                                        8

   1243
                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   1244

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 89-A Conv., L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 89-A Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 89-A Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                       2
   1245

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                       2000             1999
                                                   -----------      -----------
                                                              
              ASSETS
              ------
Current assets:
  Cash                                             $    49,781      $    58,311
  Accounts receivable - oil and gas sales               57,620           37,719
                                                   -----------      -----------

         Total current assets                          107,401           96,030
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               2,205,981        2,203,522
Accumulated depletion                               (1,860,437)      (1,832,074)
                                                   -----------      -----------

         Net oil and gas properties                    345,544          371,448
                                                   -----------      -----------

                                                   $   452,945      $   467,478
                                                   ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                     $     4,194      $     5,804

Partners' capital:
  Managing general partner                               4,556            4,685
  Limited partners (2,797 interests)                   444,195          456,989
                                                   -----------      -----------

                                                       448,751          461,674
                                                   -----------      -----------

                                                   $   452,945      $   467,478
                                                   ===========      ===========



   The accompanying notes are an integral part of these financial statements.


                                       3
   1246

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                          2000          1999          1998
                                                       ---------     ---------     ---------
                                                                          
Revenues:
  Oil and gas                                          $ 383,529     $ 241,781     $ 196,186
  Interest                                                 4,022         2,353         2,629
  Gain on disposition of assets                            1,765         1,483           648
                                                       ---------     ---------     ---------

                                                         389,316       245,617       199,463
                                                       ---------     ---------     ---------

Costs and expenses:
  Oil and gas production                                 135,124       118,700       121,865
  General and administrative                              12,370         9,612         7,006
  Impairment of oil and gas properties                     6,198            --       103,108
  Depletion                                               22,165        39,348       117,246
                                                       ---------     ---------     ---------

                                                         175,857       167,660       349,225
                                                       ---------     ---------     ---------

Net income (loss)                                      $ 213,459     $  77,957     $(149,762)
                                                       =========     =========     =========

Allocation of net income (loss):
  Managing general partner                             $   2,135     $     780     $  (1,498)
                                                       =========     =========     =========

  Limited partners                                     $ 211,324     $  77,177     $(148,264)
                                                       =========     =========     =========

Net income (loss) per limited partnership interest     $   75.55     $   27.59     $  (53.01)
                                                       =========     =========     =========



   The accompanying notes are an integral part of these financial statements.


                                       4
   1247

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                            Managing
                                            general       Limited
                                            partner       partners         Total
                                           ---------      ---------      ---------

                                                                
Partners' capital at January 1, 1998       $   7,016      $ 687,886      $ 694,902

  Distributions                                 (806)       (79,919)       (80,725)

  Net loss                                    (1,498)      (148,264)      (149,762)
                                           ---------      ---------      ---------

Partners' capital at December 31, 1998         4,712        459,703        464,415

  Distributions                                 (807)       (79,891)       (80,698)

  Net income                                     780         77,177         77,957
                                           ---------      ---------      ---------

Partners' capital at December 31, 1999         4,685        456,989        461,674

  Distributions                               (2,264)      (224,118)      (226,382)

  Net income                                   2,135        211,324        213,459
                                           ---------      ---------      ---------

Partners' capital at December 31, 2000     $   4,556      $ 444,195      $ 448,751
                                           =========      =========      =========



   The accompanying notes are an integral part of these financial statements.


                                       5
   1248

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                          2000           1999           1998
                                                       ---------      ---------      ---------
                                                                            
Cash flows from operating activities:
  Net income (loss)                                    $ 213,459      $  77,957      $(149,762)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Depletion                                           22,165         39,348        117,246
      Impairment of oil and gas properties                 6,198             --        103,108
      Gain on disposition of assets                       (1,765)        (1,483)          (648)
  Changes in assets and liabilities:
      Accounts receivable                                (19,901)       (15,731)         6,119
      Accounts payable                                    (1,610)           (17)        (3,072)
                                                       ---------      ---------      ---------

         Net cash provided by operating activities       218,546        100,074         72,991
                                                       ---------      ---------      ---------

Cash flows from investing activities:
  (Additions) deletions to oil and gas properties         (2,459)           197         (9,993)
  Proceeds from disposition of assets                      1,765          1,483            648
                                                       ---------      ---------      ---------

         Net cash provided by (used in) investing
            activities                                      (694)         1,680         (9,345)
                                                       ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                        (226,382)       (80,698)       (80,725)
                                                       ---------      ---------      ---------

Net increase (decrease) in cash                           (8,530)        21,056        (17,079)
Cash at beginning of year                                 58,311         37,255         54,334
                                                       ---------      ---------      ---------

Cash at end of year                                    $  49,781      $  58,311      $  37,255
                                                       =========      =========      =========



   The accompanying notes are an integral part of these financial statements.


                                       6
   1249

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 89-A Conv., L.P. (the "Partnership") was organized in
1989 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1990. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.


                                       7
   1250

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the



                                       8
   1251

Partnership recognized a non-cash impairment provision of $6,198 and $103,108
related to its proved oil and gas properties during 2000 and 1998, respectively.

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $52,175 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                          2000           1999           1998
                                                       ---------      ---------      ---------

                                                                            
Net income (loss) per statements of operations         $ 213,459      $  77,957      $(149,762)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                            18,394         35,333        113,374
Impairment of oil and gas properties for financial
  reporting purposes                                       6,198             --        103,108
Other, net                                                  (560)        (1,305)         1,416
                                                       ---------      ---------      ---------

    Net income per Federal income tax returns          $ 237,491      $ 111,985      $  68,136
                                                       =========      =========      =========


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                         2000          1999       1998
                      ---------     ---------     ------

                                         
Development costs     $   2,459     $   4,107     $5,690
                      =========     =========     ======


        Capitalized oil and gas properties consist of the following:



                                            2000             1999
                                         -----------      -----------
                                                    
Proved properties:
  Property acquisition costs             $    93,966      $    93,966
  Completed wells and equipment            2,112,015        2,109,556
                                         -----------      -----------

                                           2,205,981        2,203,522
Accumulated depletion                     (1,860,437)      (1,832,074)
                                         -----------      -----------

          Net oil and gas properties     $   345,544      $   371,448
                                         ===========      ===========



                                       9
   1252

NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                  2000        1999        1998
                                                -------     -------     -------
                                                               
Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                 $52,987     $52,678     $51,730

Reimbursement of general and administrative
  expenses                                      $10,994     $ 7,203     $ 5,808


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 89-A Conv., Ltd. ("EMPL"), Parker & Parsley 89-A, L.P. and the
Partnership (the "Partnerships") are parties to the Program agreement. EMPL is a
limited partnership organized for the benefit of certain employees of Pioneer
USA. EMPL was merged with Pioneer USA on December 28, 2000,

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:



                                                             Pioneer USA (1)   Partnerships (2)
                                                             ---------------   ----------------
                                                                         
Revenues:
  Proceeds from disposition of depreciable and
    depletable properties -
     First three years                                          14.141414%      85.858586%
     After first three years                                    19.191919%      80.808081%
  All other revenues -
     First three years                                          14.141414%      85.858586%
     After first three years                                    19.191919%      80.808081%

Costs and expenses:
  Lease acquisition costs, drilling and completion
    costs and all other costs                                    9.090909%      90.909091%
  Operating costs, reporting and legal expenses and
    and general and administrative expenses -
     First three years                                          14.141414%      85.858586%
     After first three years                                    19.191919%      80.808081%


    (1) Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level.

    (2) The allocation between the Partnership and Parker & Parsley 89-A, L.P.
        is 25.166457% and 74.833543%, respectively.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.


                                       10
   1253



                                           Oil and NGLs       Gas
                                              (bbls)         (mcf)
                                           ------------    --------
                                                     
Net proved reserves at January 1, 1998        189,854       326,511
Revisions                                     (83,618)     (110,279)
Production                                    (14,102)      (21,106)
                                             --------      --------

Net proved reserves at December 31, 1998       92,134       195,126
Revisions                                     106,866       158,479
Production                                    (14,166)      (20,484)
                                             --------      --------

Net proved reserves at December 31, 1999      184,834       333,121
Revisions                                      30,916       (27,906)
Production                                    (13,092)      (20,057)
                                             --------      --------

Net proved reserves at December 31, 2000      202,658       285,158
                                             ========      ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.34 per barrel of NGLs and $8.31 per mcf of gas,
discounted at 10% was approximately $1,685,000 and undiscounted $3,469,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.


                                       11
   1254



                                                                For the years ended December 31,
                                                               ---------------------------------
                                                                2000         1999         1998
                                                               -------      -------      -------
                                                                        (in thousands)
                                                                                
Oil and gas producing activities:
  Future cash inflows                                          $ 6,835      $ 4,546      $ 1,057
  Future production costs                                       (3,367)      (2,613)        (750)
                                                               -------      -------      -------

                                                                 3,468        1,933          307
  10% annual discount factor                                    (1,783)        (891)        (101)
                                                               -------      -------      -------

  Standardized measure of discounted future net cash flows     $ 1,685      $ 1,042      $   206
                                                               =======      =======      =======




                                                         For the years ended December 31,
                                                        ---------------------------------
                                                          2000         1999         1998
                                                        -------      -------      -------
                                                                   (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs          $  (248)     $  (123)     $   (74)
    Net changes in prices and production costs              765          461         (511)
    Revisions of estimated future development costs          --           --           --
    Revisions of previous quantity estimates                196          720         (138)
    Accretion of discount                                   104           20           87
    Changes in production rates, timing and other          (174)        (242)         (27)
                                                        -------      -------      -------

    Change in present value of future net revenues          643          836         (663)
                                                        -------      -------      -------

    Balance, beginning of year                            1,042          206          869
                                                        -------      -------      -------

    Balance, end of year                                $ 1,685      $ 1,042      $   206
                                                        =======      =======      =======


NOTE 8. MAJOR CUSTOMERS

  The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:



                                           2000          1999         1998
                                           ----          ----         ----
                                                             
        Plains Marketing, L.P.               63%          62%           -
        Genesis Crude Oil, L.P.               -            -           59%
        Western Gas Resources, Inc.           3%           3%          12%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $22,502 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The


                                       12
   1255

        majority of the Partnership's oil and gas revenues are received directly
        by the Partnership, however, a portion of the oil and gas revenue is
        initially received by Pioneer USA prior to being paid to the
        Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $2,797,000. The
        managing general partner is required to contribute amounts equal to 1%
        of initial Partnership capital less commission and organization and
        offering costs allocated to the limited partners and to contribute
        amounts necessary to pay costs and expenses allocated to it under the
        Partnership agreement to the extent its share of revenues does not cover
        such costs.


                                       13
   1256

                        PARKER & PARSLEY 89-A CONV., L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 59% to $383,529 for 2000 as
compared to $241,781 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 8,466
barrels of oil, 4,626 barrels of natural gas liquids ("NGLs") and 20,057 mcf of
gas were sold, or 16,435 barrel of oil equivalents ("BOEs"). In 1999, 9,190
barrels of oil, 4,976 barrels of NGLs and 20,484 mcf of gas were sold, or 17,580
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.48, or 73%, from
$17.11 in 1999 to $29.59 in 2000. The average price received per barrel of NGLs
increased $5.88, or 62%, from $9.54 in 1999 to $15.42 in 2000. The average price
received per mcf of gas increased 70% from $1.81 in 1999 to $3.07 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

During 2000 and 1999, gains on disposition of assets of $1,765 and $1,483,
respectively, were attributable to credits received from equipment salvage on
one fully depleted well in each year.

Total costs and expenses increased in 2000 to $175,856 as compared to $167,660
in 1999, an increase of $8,196, or 5%. The increase was due to increases in
production costs, the impairment of oil and gas properties and general and
administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $135,124 in 2000 and $118,700 in 1999, resulting in a
$16,424 increase, or 14%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
29% from $9,612 in 1999 to $12,370 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $10,994 in 2000 and $7,203 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $6,198 related to its oil and gas properties during 2000.

   1257

Depletion was $22,165 in 2000 as compared to $39,348 in 1999, representing a
decrease of $17,183, or 44%. This decrease was primarily due to a 28,723 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 23% to $241,781 from
$196,186 in 1998. The increase in revenues resulted from higher average prices
received. In 1999, 9,190 barrels of oil, 4,976 barrels of natural gas liquids
("NGLs") and 20,484 mcf of gas were sold, or 17,580 barrel of oil equivalents
("BOEs"). In 1998, 9,782 barrels of oil, 4,320 barrels of NGLs and 21,106 mcf of
gas were sold, or 17,620 BOEs.

The average price received per barrel of oil increased $3.88, or 29%, from
$13.23 in 1998 to $17.11 in 1999. The average price received per barrel of NGLs
increased $2.59, or 37%, from $6.95 in 1998 to $9.54 in 1999. The average price
received per mcf of gas increased 4% from $1.74 in 1998 to $1.81 in 1999.

During 1999, gain on disposition of assets of $1,483 was attributable to credits
received from equipment salvage on one active well. Gain on disposition of
assets of $648 was attributable to credits received in 1998 from the disposal of
oil and gas equipment on a well that was plugged and abandoned in a prior year.

Total costs and expenses decreased in 1999 to $167,660 as compared to $349,225
in 1998, a decrease of $181,565, or 52%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $118,700 in 1999 and $121,865 in 1998, resulting in a
$3,165 decrease, or 3%. The decrease was due to declines in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes.

During this period, G&A increased 37% from $7,006 in 1998 to $9,612 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $7,203 in
1999 and $5,808 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $103,108 related to its
oil and gas properties during 1998.

Depletion was $39,348 in 1999 compared to $117,246 in 1998, representing a
decrease of $77,898, or 66%. This decrease was primarily due to an increase in
proved reserves of 70,433 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

   1258

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $118,472 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $143,417, offset by increases in production costs paid
of $16,424, G&A expenses paid of $2,758 and working capital of $5,763. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $171,552 to oil and gas receipts,
offset by $28,135 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and workover and well maintenance
costs incurred to stimulate well production. The increase in G&A was primarily
due to higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were
related to equipment upgrades on active properties.

During 2000 and 1999, proceeds from disposition of assets of $1,765 and $1,483,
respectively, were from equipment credits received on an active well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $226,382, of which $2,264 was
distributed to the managing general partner and $224,118 to the limited
partners. In 1999, cash distributions to the partners were $80,698, of which
$807 was distributed to the managing general partner and $79,891 to the limited
partners.

   1259



                        PARKER & PARSLEY 89-A CONV., L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   81,009   $  383,529   $  241,781   $  196,186   $  288,192   $  381,014
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $    6,198   $       --   $  103,108   $  178,895   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   41,603   $  213,459   $   77,957   $ (149,762)  $  (90,749)  $  163,974
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      416   $    2,135   $      780   $   (1,498)  $     (907)  $    1,640
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   41,187   $  211,324   $   77,177   $ (148,264)  $  (89,842)  $  162,334
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    14.73   $    75.55   $    27.59   $   (53.01)  $   (32.12)  $    58.04
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    17.96   $    80.13   $    28.56   $    28.57   $    62.59   $    68.91
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  458,988   $  452,945   $  467,478   $  465,932   $  703,794   $  970,154
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1260

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 89-A, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

               PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
89-A, L.P., and supplements the proxy statement/prospectus dated               ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 89-A, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1261

                           PARKER & PARSLEY 89-A, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                     
Aggregate Initial Investment by the Limited Partners(a)                                                 $      8,317

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                             $      8,902

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)   $      2,715

Merger Value per $1,000 Limited Partner Investment(b), (c)                                              $     330.57

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                           3.46 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                     $     154.43

      --    as of December 31, 2000(c)                                                                  $     159.61

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                       $     309.04

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                         $     320.88

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)           $        149



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   1262

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-26097-01


                           PARKER & PARSLEY 89-A, L.P.
             (Exact name of Registrant as specified in its charter)

                        Delaware                             75-2297058
            ---------------------------------          ---------------------
             (State or other jurisdiction of              (I.R.S. Employer
             incorporation or organization)            Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
           (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [X]   No [ ]


   1263



                           PARKER & PARSLEY 89-A, L.P.

                                TABLE OF CONTENTS




                                                                        Page

                                                                      
                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000......................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000...........................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000...........................    6

           Notes to Financial Statements.............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K..........................   10

           Signatures................................................   11



                                        2

   1264



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                     March 31,      December 31,
                                                       2001             2000
                                                    -----------     -----------
                                                    (Unaudited)

                                                              
                 ASSETS

Current assets:
  Cash                                               $  137,887      $  154,704
  Accounts receivable - oil and gas sales               165,298         171,226
                                                     ----------      ----------
        Total current assets                            303,185         325,930
                                                     ----------      ----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                6,395,399       6,559,576
Accumulated depletion                                (5,385,459)     (5,531,818)
                                                     ----------      ----------
        Net oil and gas properties                    1,009,940       1,027,758
                                                     ----------      ----------
                                                     $1,313,125      $1,353,688
                                                     ==========      ==========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $   15,593      $   12,645

Partners' capital:
  Managing general partner                               13,166          13,602
  Limited partners (8,317 interests)                  1,284,366       1,327,441
                                                     ----------      ----------
                                                      1,297,532       1,341,043
                                                     ----------      ----------
                                                     $1,313,125      $1,353,688
                                                     ==========      ==========



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   1265



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                         Three months ended
                                                             March 31,
                                                      -------------------------
                                                         2001           2000
                                                      ----------     ----------

                                                               
Revenues:
  Oil and gas                                          $ 327,815      $ 240,830
  Interest                                                 2,676          2,367
  Gain on disposition of assets                           11,040             --
                                                       ---------      ---------
                                                         341,531        243,197
                                                       ---------      ---------
Costs and expenses:
  Oil and gas production                                  98,933         93,383
  General and administrative                              11,707          7,458
  Depletion                                               17,818         18,800
  Abandoned property                                       8,824             --
                                                       ---------      ---------
                                                         137,282        119,641
                                                       ---------      ---------
Net income                                             $ 204,249      $ 123,556
                                                       =========      =========
Allocation of net income:
  Managing general partner                             $   2,042      $   1,236
                                                       =========      =========
  Limited partners                                     $ 202,207      $ 122,320
                                                       =========      =========
Net income per limited partnership interest            $   24.31      $   14.71
                                                       =========      =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   1266



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                  Managing
                                  general          Limited
                                  partner          partners            Total
                                -----------       -----------       -----------


                                                           
Balance at January 1, 2001      $    13,602       $ 1,327,441       $ 1,341,043

    Distributions                    (2,478)         (245,282)         (247,760)

    Net income                        2,042           202,207           204,249
                                -----------       -----------       -----------

Balance at March 31, 2001       $    13,166       $ 1,284,366       $ 1,297,532
                                ===========       ===========       ===========







         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   1267



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                         Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                            $ 204,249     $ 123,556
  Adjustments to reconcile net income to net
     cash provided by operating activities:
        Depletion                                          17,818        18,800
        Gain on disposition of assets                     (11,040)           --
  Changes in assets and liabilities:
        Accounts receivable                                 5,928        (3,757)
        Accounts payable                                   13,988         2,273
                                                        ---------     ---------
          Net cash provided by operating activities       230,943       140,872
                                                        ---------     ---------
Cash flows used in investing activities:
  Additions to oil and gas properties                          --        (1,394)

Cash flows used in financing activities:
  Cash distributions to partners                         (247,760)     (150,878)
                                                        ---------     ---------
Net decrease in cash                                      (16,817)      (11,400)
Cash at beginning of period                               154,704       180,301
                                                        ---------     ---------
Cash at end of period                                   $ 137,887     $ 168,901
                                                        =========     =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   1268



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 89-A, L.P. (the "Partnership") is a limited partnership
organized in 1989 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 36% to $327,815 for the three
months ended March 31, 2001 as compared to $240,830 for the same period in 2000.
The increase in revenues resulted from higher average prices received and a
slight increase in production. For the three months ended March 31, 2001, 6,466
barrels of oil, 2,508 barrels of natural gas liquids ("NGLs") and 16,665 mcf of
gas were sold, or 11,752 barrel of oil equivalents ("BOEs"). For the three

                                        7

   1269



months ended March 31, 2000, 6,179 barrels of oil, 3,187 barrels of NGLs and
14,142 mcf of gas were sold, or 11,723 BOEs.

The average price received per barrel of oil increased $.62, or 2%, from $27.48
for the three months ended March 31, 2000 to $28.10 for the same period in 2001.
The average price received per barrel of NGLs increased $3.52, or 25%, from
$13.84 for the three months ended March 31, 2000 to $17.36 for the same period
in 2001. The average price received per mcf of gas increased 223% from $1.91
during the three months ended March 31, 2000 to $6.16 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gain on disposition of assets of $11,040 was recognized during the three months
ended March 31, 2001 from equipment salvage received on one well plugged and
abandoned during the current period. Abandoned property costs of $8,824 were
incurred to plug and abandon this well.

Costs and Expenses:

Total costs and expenses increased to $137,282 for the three months ended March
31, 2001 as compared to $119,641 for the same period in 2000, an increase of
$17,641, or 15%. This increase was due to increases in abandoned property costs,
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $98,933 for the three months ended March 31, 2001 and
$93,383 for the same period in 2000 resulting in a $5,550 increase, or 6%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices, offset by lower well maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 57%, from $7,458 for the three months ended March 31, 2000 to $11,707
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $17,818 for the three months ended March 31, 2001 as compared to
$18,800 for the same period in 2000, a decrease of $982, or 5%. This decrease
was primarily due to downward revisions to proved reserves on several wells
during the three months ended March 31, 2001, offset by an increase in oil
production of 287 barrels for the period ended March 31, 2001 as compared to the
same period in 2000.

                                        8

   1270



Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $90,071 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $87,294 in oil and gas sales receipts
and a reduction in working capital of $21,400, offset by increases in abandoned
property costs of $8,824, production costs of $5,550 and G&A expenses of $4,249.
The increase in oil and gas receipts resulted from the increase in commodity
prices during 2001 which contributed an additional $75,474 to oil and gas
receipts and $11,820 resulting from the increase in production during 2001 as
compared to the same period in 2000. The increase in abandoned property costs
was due to one well being plugged and abandoned in the current year. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices, offset by lower well maintenance
costs. The increase in G&A was primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's investing activities during the three months ended March 31,
2000 were related to upgrades of oil and gas equipment on active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $247,760, of which $2,478 was distributed to the managing general partner
and $245,282 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $150,878, of which $1,509 was
distributed to the managing general partner and $149,369 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

                                        9

   1271




----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)      Exhibits - none

(b)      Reports on Form 8-K - none.




                                       10

   1272


                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 89-A, L.P.


                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 11, 2001                By:     /s/ Rich Dealy
                                            ---------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer




                                       11



   1273
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-26097-01


                           PARKER & PARSLEY 89-A, L.P.
             (Exact name of Registrant as specified in its charter)

                   DELAWARE                             75-2297058
        -------------------------------           ----------------------
        (State or other jurisdiction of             (I.R.S. Employer
        incorporation or organization)            Identification Number)



                                                                               
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                      75039
----------------------------------------------------------------                  -------------
            (Address of principal executive offices)                                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES /X/ NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. /X/

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$8,212,000.

        As of March 8, 2001, the number of outstanding limited partnership
interests was 8,317.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   1274

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 89-A, L.P. (the "Partnership") is a limited partnership
organized in 1989 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 8,317 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 63% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.

The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and



                                       2
   1275

ruptures and discharges of toxic substances or gases that could expose the
Partnership to substantial liability due to pollution and other environmental
damages. Although the Partnership believes that its business operations do not
impair environmental quality and that its costs of complying with any applicable
environmental regulations are not currently significant, the Partnership cannot
predict what, if any, effect these environmental regulations may have on its
current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located in
the Spraberry Trend area of West Texas were acquired by the Partnership,
resulting in the Partnership's participation in the drilling of 33 oil and gas
wells. One well has been plugged and abandoned. At December 31, 2000, 32 wells
were producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.


                                       3
   1276

                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTEREST AND LIMITED PARTNERSHIP
           DISTRIBUTIONS

At March 8, 2001, the Partnership had 8,317 outstanding limited partnership
interests held of record by 609 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $666,425 and $237,558, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                    2000         1999          1998         1997         1996
                                 ----------   ----------    ----------   ----------   ----------
                                                                       
Operating results:
-----------------
  Oil and gas sales              $1,140,280   $  718,969    $  583,396   $  856,926   $1,132,944
                                 ==========   ==========    ==========   ==========   ==========

  Impairment of oil and gas
    properties                   $   18,391   $      -      $  306,826   $  531,929   $      -
                                 ==========   ==========    ==========   ==========   ==========

  Net income (loss)              $  634.127   $  231,838    $ (444,718)  $ (269,363)  $  488,019
                                 ==========   ==========    ==========   ==========   ==========

  Allocation of net income
    (loss):
     Managing general partner    $    6,341   $    2,318    $   (4,447)  $   (2,693)  $    4,880
                                 ==========   ==========    ==========   ==========   ==========

     Limited partners            $  627,786   $  229,520    $ (440,271)  $ (266,670)  $  483,139
                                 ==========   ==========    ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest         $    75.48   $    27.60    $   (52.94)  $   (32.06)  $    58.09
                                 ==========   ==========    ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest         $    80.13   $    28.56    $    28.57   $    62.59   $    68.92
                                 ==========   ==========    ==========   ==========   ==========

At year end:
-----------
  Identifiable assets            $1,353,688   $1,397,183    $1,392,439   $2,099,131   $2,890,740
                                 ==========   ==========    ==========   ==========   ==========





                                       4
   1277



ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
           RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 59% to $1,140,280 for 2000 as
compared to $718,969 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 25,176
barrels of oil, 13,747 barrels of natural gas liquids ("NGLs") and 59,638 mcf of
gas were sold, or 48,863 barrel of oil equivalents ("BOEs"). In 1999, 27,333
barrels of oil, 14,796 barrels of NGLs and 60,905 mcf of gas were sold, or
52,280 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.48, or 73%, from
$17.11 in 1999 to $29.59 in 2000. The average price received per barrel of NGLs
increased $5.88, or 62%, from $9.54 in 1999 to $15.42 in 2000. The average price
received per mcf of gas increased 70% from $1.81 in 1999 to $3.07 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gains on disposition of assets of $5,248 and $4,410 in 2000 and 1999,
respectively, were attributable to equipment credits on one fully depleted well
in each year.

Total costs and expenses increased in 2000 to $523,646 as compared to $498,672
in 1999, an increase of $24,974, or 5%. The increase was primarily due to
increases in production costs, the impairment of oil and gas properties and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $402,118 in 2000 and $352,977 in 1999, resulting in an
increase of $49,141, or 14%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
31% from $28,521 in 1999 to $37,259 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $32,691 in 2000 and $21,420 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   1278


In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $18,391 related to its oil and gas properties during 2000.

Depletion was $65,878 in 2000 as compared to $117,174 in 1999, representing a
decrease of $51,296, or 44%. This decrease was primarily due to a 85,285 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 23% to $718,969 from
$583,396 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 27,333 barrels of oil,
14,796 barrels of NGLs and 60,905 mcf of gas were sold, or 52,280 BOEs. In 1998,
29,084 barrels of oil, 12,847 barrels of NGLs and 62,751 mcf of gas were sold,
or 52,390 BOEs.

The average price received per barrel of oil increased $3.88, or 29%, from
$13.23 in 1998 to $17.11 in 1999. The average price received per barrel of NGLs
increased $2.59, or 37%, from $6.95 in 1998 to $9.54 in 1999. The average price
received per mcf of gas increased 4% from $1.74 in 1998 to $1.81 in 1999.

Gain on disposition of assets of $4,410 in 1999 was attributable to equipment
credits on one fully depleted well. During 1998, gain on disposition of assets
of $1,926 was attributable to credits received from the disposal of oil and gas
equipment on a well that was plugged and abandoned in a prior year.

Total costs and expenses decreased in 1999 to $498,672 as compared to $1,038,152
in 1998, a decrease of $539,480, or 52%. The decrease was primarily due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $352,977 in 1999 and $362,377 in 1998, resulting in a
$9,400 decrease, or 3%. The decrease was due to declines in ad valorem taxes and
well maintenance costs, offset by an increase in workover costs incurred to
stimulate well production and an increase in production taxes due to increased
oil and gas revenues.

During this period, G&A increased 38% from $20,635 in 1998 to $28,521 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $21,420 in
1999 and $17,270 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $306,826 related to its
oil and gas properties during 1998.



                                       6
   1279

Depletion was $117,174 in 1999 compared to $348,314 in 1998. This represented a
decrease of $231,140, or 66%. This decrease was primarily due to an increase in
proved reserves of 209,480 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $351,738 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $426,425, offset by increases in production costs paid
of $49,141, G&A expenses paid of $8,738 and working capital of $16,808. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $510,320 to oil and gas receipts,
offset by $83,895 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional workover and well
maintenance costs incurred to stimulate well production. The increase in G&A was
primarily due to higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during 2000 and 1999 were related to
expenditures for equipment upgrades on active oil and gas properties.

Proceeds from disposition of assets of $5,248 and $4,410 recognized in 2000 and
1999, respectively, were from equipment credits received on one fully depleted
well in each year.

Net Cash Used in Financing Activities

For 2000, cash distributions to the partners were $673,157, of which $6,732 was
distributed to the managing general partner and $666,425 to the limited
partners. For 1999, cash distributions to the partners were $239,958, of which
$2,400 was distributed to the managing general partner and $237,558 to the
limited partners.




                                       7
   1280



ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                        Page
                                                                                        ----
                                                                                     
Financial Statements of Parker & Parsley 89-A, L.P.:
 Independent Auditors' Report.........................................................     9
 Balance Sheets as of December 31, 2000 and 1999......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14






                                       8
   1281




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 89-A, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 89-A, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 89-A, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                           Ernst & Young LLP

Dallas, Texas
March 9, 2001



                                       9
   1282


                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                      2000             1999
                                                   -----------      -----------
                                                              
              ASSETS
              ------

Current assets:
  Cash                                             $   154,704      $   180,301
  Accounts receivable - oil and gas sales              171,226          112,165
                                                   -----------      -----------

      Total current assets                             325,930          292,466
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               6,559,576        6,552,266
Accumulated depletion                               (5,531,818)      (5,447,549)
                                                   -----------      -----------

      Net oil and gas properties                     1,027,758        1,104,717
                                                   -----------      -----------

                                                   $ 1,353,688      $ 1,397,183
                                                   ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                     $    12,645      $    17,110

Partners' capital:
  Managing general partner                              13,602           13,993
  Limited partners (8,317 interests)                 1,327,441        1,366,080
                                                   -----------      -----------

                                                     1,341,043        1,380,073
                                                   -----------      -----------

                                                   $ 1,353,688      $ 1,397,183
                                                   ===========      ===========








   The accompanying notes are an integral part of these financial statements.



                                       10
   1283



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                              2000           1999            1998
                                           ----------     ----------     -----------
                                                                
Revenues:
  Oil and gas                              $1,140,280     $  718,969     $   583,396
  Interest                                     12,245          7,131           8,112
  Gain on disposition of assets                 5,248          4,410           1,926
                                           ----------     ----------     -----------

                                            1,157,773        730,510         593,434
                                           ----------     ----------     -----------

Costs and expenses:
  Oil and gas production                      402,118        352,977         362,377
  General and administrative                   37,259         28,521          20,635
  Impairment of oil and gas properties         18,391            -           306,826
  Depletion                                    65,878        117,174         348,314
                                           ----------     ----------     -----------

                                              523,646        498,672       1,038,152
                                           ----------     ----------     -----------

Net income (loss)                          $  634,127     $  231,838     $  (444,718)
                                           ==========     ==========     ===========

Allocation of net income (loss):
  Managing general partner                 $    6,341     $    2,318     $    (4,447)
                                           ==========     ==========     ===========

  Limited partners                         $  627,786     $  229,520     $  (440,271)
                                           ==========     ==========     ===========

Net income (loss) per limited
  partnership interest                     $    75.48     $    27.60     $    (52.94)
                                           ==========     ==========     ===========




   The accompanying notes are an integral part of these financial statements.



                                       11
   1284



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL





                                           Managing
                                            general       Limited
                                            partner       partners           Total
                                           --------      -----------      -----------

                                                                 
Partners' capital at January 1, 1998       $ 20,922      $ 2,052,031      $ 2,072,953

  Distributions                              (2,400)        (237,642)        (240,042)

  Net loss                                   (4,447)        (440,271)        (444,718)
                                           --------      -----------      -----------

Partners' capital at December 31, 1998       14,075        1,374,118        1,388,193

  Distributions                              (2,400)        (237,558)        (239,958)

  Net income                                  2,318          229,520          231,838
                                           --------      -----------      -----------

Partners' capital at December 31, 1999       13,993        1,366,080        1,380,073

  Distributions                              (6,732)        (666,425)        (673,157)

  Net income                                  6,341          627,786          634,127
                                           --------      -----------      -----------

Partners' capital at December 31, 2000     $ 13,602      $ 1,327,441      $ 1,341,043
                                           ========      ===========      ===========



        The accompanying notes are an integral part of these statements.



                                       12
   1285



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                         2000           1999           1998
                                                       ---------      ---------      ---------

                                                                            
Cash flows from operating activities:
  Net income (loss)                                    $ 634,127      $ 231,838      $(444,718)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
       Impairment of oil and gas properties               18,391            -          306,826
       Depletion                                          65,878        117,174        348,314
       Gain on disposition of assets                      (5,248)        (4,410)        (1,926)
  Changes in assets and liabilities:
       Accounts receivable                               (59,061)       (46,785)        18,178
       Accounts payable                                   (4,465)            67         (9,135)
                                                       ---------      ---------      ---------

         Net cash provided by operating activities       649,622        297,884        217,539
                                                       ---------      ---------      ---------

Cash flows from investing activities:
  (Additions) deletions to oil and gas properties         (7,310)           584        (29,716)
  Proceeds from disposition of assets                      5,248          4,410          1,926
                                                       ---------      ---------      ---------

         Net cash provided by (used in)
           investing activities                           (2,062)         4,994        (27,790)
                                                       ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                        (673,157)      (239,958)      (240,042)
                                                       ---------      ---------      ---------

Net increase (decrease) in cash                          (25,597)        62,920        (50,293)
Cash at beginning of year                                180,301        117,381        167,674
                                                       ---------      ---------      ---------

Cash at end of year                                    $ 154,704      $ 180,301      $ 117,381
                                                       =========      =========      =========



   The accompanying notes are an integral part of these financial statements.



                                       13
   1286



                           PARKER & PARSLEY 89-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 89-A, L.P. (the "Partnership") is a limited partnership
organized in 1989 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.



                                       14
   1287

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $18,391 and $306,826
related to its proved oil and gas properties during 2000 and 1998, respectively.

NOTE 4.    INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $155,457 greater than the tax basis at December 31, 2000.



                                       15
   1288

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                         2000           1999           1998
                                                       ---------      ---------      ---------

                                                                            
Net income (loss)  per statements of operations        $ 634,127      $ 231,838      $(444,718)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                            54,665        105,234        336,801
Impairment of oil and gas properties for financial
  reporting purposes                                      18,391            -          306,826
Salvage income                                               -              -              -
Other, net                                                (1,709)        (3,610)         3,948
                                                       ---------      ---------      ---------

      Net income per  Federal income tax
         returns                                       $ 705,474      $ 333,462      $ 202,857
                                                       =========      =========      =========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the net costs incurred, whether capitalized
or expensed, related to the Partnership's oil and gas producing activities for
the years ended December 31:



                                                     2000           1999           1998
                                                   ---------      --------       --------

                                                                        
      Development costs                            $   7,310      $ 12,213       $ 16,919
                                                   =========      ========       ========



      Capitalized oil and gas properties consist of the following:



                                        2000              1999
                                     -----------      -----------

                                                
Proved properties:
  Property acquisition costs         $   279,410      $   279,410
  Completed wells and equipment        6,280,166        6,272,856
                                     -----------      -----------

                                       6,559,576        6,552,266
Accumulated depletion                 (5,531,818)      (5,447,549)
                                     -----------      -----------

      Net oil and gas properties     $ 1,027,758      $ 1,104,717
                                     ===========      ===========





                                       16

   1289

NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                     2000          1999           1998
                                                   ---------     ---------      ---------

                                                                       
  Payment of lease operating and supervision
    charges in accordance with standard
    industry operating agreements                  $ 157,560     $ 156,639      $ 153,822

  Reimbursement of general and administrative
    expenses                                       $  32,691     $  21,420      $  17,270


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 89-A Conv., Ltd. ("EMPL"), Parker & Parsley 89-A Conv., L.P. and
the Partnership (the "Partnerships") are parties to the Program agreement. EMPL
is a limited partnership organized for the benefit of certain employees of
Pioneer USA. EMPL was merged with Pioneer USA on December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                              Pioneer USA (1)  Partnerships (2)
                                                              ---------------  ----------------
                                                                         
  Revenues:
     Proceeds from disposition of depreciable and
       depletable properties -
         First three years                                      14.141414%        85.858586%
         After first three years                                19.191919%        80.808081%
     All other revenues -
         First three years                                      14.141414%        85.858586%
         After first three years                                19.191919%        80.808081%
  Costs and expenses:
     Lease acquisition costs, drilling and completion costs
       and all other costs                                       9.090909%        90.909091%
     Operating costs, reporting and legal expenses and
       general and administrative expenses -
         First three years                                      14.141414%        85.858586%
         After first three years                                19.191919%        80.808081%


   (1)  Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level and 105 limited partner interests owned by
        Pioneer USA.

   (2)  The allocation between the Partnership and Parker & Parsley 89-A Conv.,
        L.P. is 74.833543% and 25.166457%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared Williamson Petroleum
Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                            Oil and NGLs     Gas
                                              (bbls)         (mcf)
                                            ------------   --------

                                                     
Net proved reserves at January 1, 1998        564,653       971,094
Revisions                                    (248,699)     (328,006)
Production                                    (41,931)      (62,751)
                                             --------      --------

Net proved reserves at December 31, 1998      274,023       580,337
Revisions                                     317,834       471,328
Production                                    (42,129)      (60,905)
                                             --------      --------



                                       17
   1290


                                                     
Net proved reserves at December 31, 1999      549,728       990,760
Revisions                                      91,729       (83,266)
Production                                    (38,923)      (59,638)
                                             --------      --------

Net proved reserves at December 31, 2000      602,534       847,856
                                             ========      ========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $12.34 per barrel of NGLs and $8.31 per mcf of gas,
discounted at 10% was approximately $5,009,000 and undiscounted was $10,314,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

      The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                 For the years ended December 31,
                                                               -----------------------------------
                                                                 2000          1999          1998
                                                               --------      --------      -------
                                                                          (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                          $ 20,322      $ 13,520      $ 3,146
  Future production costs                                       (10,008)       (7,771)      (2,232)
                                                               --------      --------      -------

                                                                 10,314         5,749          914
  10% annual discount factor                                     (5,305)       (2,649)        (301)
                                                               --------      --------      -------

  Standardized measure of discounted future net cash flows     $  5,009      $  3,100      $   613
                                                               ========      ========      =======



                                       18
   1291



                                                      For the years ended December 31,
                                                     ----------------------------------
                                                       2000         1999         1998
                                                               (in thousands)
                                                                      
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs         $  (738)     $  (366)     $  (221)
  Net changes in prices and production costs           2,277        1,372       (1,520)
  Revisions of previous quantity estimates               582        2,141         (409)
  Accretion of discount                                  310           62          259
  Changes in production rates, timing and other         (522)        (722)         (81)
                                                     -------      -------      -------

  Change in present value of future net revenues       1,909        2,487       (1,972)
                                                     -------      -------      -------

  Balance, beginning of year                           3,100          613        2,585
                                                     -------      -------      -------

  Balance, end of year                               $ 5,009      $ 3,100      $   613
                                                     =======      =======      =======


NOTE 8.    MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       -------

                                                                       
          Plains Marketing, L.P.                      63%           62%             -
          Genesis Crude Oil, L.P.                      -             -             59%
          Western Gas Resources, Inc.                  3%            3%            12%


      At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $66,937 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the limited partnership agreement, the managing general partner pays
      1% of the Partnership's acquisition, drilling and completion costs and 1%
      of its operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.



                                       19
   1292

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of $8,317,000.
      The managing general partner is required to contribute amounts equal to 1%
      of initial Partnership capital less commission and offering expenses
      allocated to the limited partners and to contribute amounts necessary to
      pay costs and expenses allocated to it under the Partnership agreement to
      the extent its share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
           AND FINANCIAL DISCLOSURE

None.



                                       20
   1293



                                    PART III

ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            45              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   1294




      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B.S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.



                                       22
   1295

ITEM 11.    EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 15% during the first three years
and approximately 20% after three years of its operating and general and
administrative expenses. In return, they are allocated approximately 15% during
the first three years and approximately 20% after three years of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)   Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 105 limited partner interests at January 1, 2001.

(b)   Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.



                                       23
   1296


ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:



                                                     2000          1999           1998
                                                   --------      ---------      --------
                                                                       
  Payment of lease operating and supervision
     charges in accordance with standard
     industry operating agreements                 $157,560      $ 156,639      $153,822
  Reimbursement of general and administrative
     expenses                                      $ 32,691      $  21,420      $ 17,270


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.



                                       24
   1297



                                     PART IV

ITEM 14.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.  Financial statements

          The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31,
                 2000, 1999 and 1998

                 Statements of partners' capital for the years ended December
                 31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31, 2000,
                 1999 and 1998

                 Notes to financial statements

      2.  Financial statement schedules

          All financial statement schedules have been omitted since the required
          information is in the financial statements or notes thereto, or is not
          applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   1298



                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                    PARKER & PARSLEY 89-A, L.P.

Dated: March 27, 2001               By:   Pioneer Natural Resources USA, Inc.
                                          Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                -------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 27, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 27, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA

/s/ Dennis E. Fagerstone            Executive Vice President and              March 27, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 27, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 27, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA

/s/ Rich Dealy                      Vice President and Chief Accounting       March 27, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       26
   1299



                           PARKER & PARSLEY 89-A, L.P.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



    Exhibit No.                             Description                            Page
    -----------                             -----------                            ----

                                                                             
       3(a)               Form of Agreement of Limited Partnership                  -
                          of Parker & Parsley 89-A, L.P. incorporated
                          by reference to Exhibit A of the Post-Effective
                          Amendment No. 1 of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(b)               Form of Limited Partner Subscription Agreement            -
                          incorporated by reference to Exhibit C of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Form of General Partner Subscription Agreement            -
                          incorporated by reference to Exhibit D of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Power of Attorney incorporated by reference               -
                          to Exhibit B of Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit 4c
                          of the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)

      10(b)               Form of Development Drilling Program                      -
                          Agreement incorporated by reference to Exhibit
                          B of the Post-Effective Amendment No. 1 of
                          the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)






                                       27
   1300



                           PARKER & PARSLEY 89-A, L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  240,830   $1,140,280   $  718,969   $  583,396   $  856,926   $1,132,944
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and gas
    properties                     $          $       --   $   18,391   $       --   $  306,826   $  531,929   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  123,556   $  634,127   $  231,838   $ (444,718)  $ (269,363)  $  488,019
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
       Managing general
          partner                  $          $    1,236   $    6,341   $    2,318   $   (4,447)  $   (2,693)  $    4,880
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

       Limited partners            $          $  122,320   $  627,786   $  229,520   $ (440,271)  $ (266,670)  $  483,139
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    14.71   $    75.48   $    27.60   $   (52.94)  $   (32.06)  $    58.09
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    17.96   $    80.13   $    28.56   $    28.57   $    62.59   $    68.92

                                   ========   ==========   ==========   ==========   ==========   ==========   ==========
At year end:
  Identifiable assets              $          $1,372,134   $1,353,688   $1,397,183   $1,392,439   $2,099,131   $2,890,740
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1301
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 89-B CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


    This document contains important information specific to Parker & Parsley
89-B Conv., L.P., and supplements the proxy statement/prospectus dated       ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


    This document contains the following information concerning Parker & Parsley
89-B Conv., L.P.:

    o    A table containing:

         --       the aggregate initial investment by the limited partners


         --       the aggregate historical limited partner distributions through
                  July 31, 2001

         --       the merger value attributable to partnership interests of
                  limited partners, excluding Pioneer USA

         --       the merger value per $1,000 limited partner investment

         --       the merger value per $1,000 limited partner investment as a
                  multiple of distributions for the past four quarterly
                  distributions including the distribution in July 2001


         --       the book value per $1,000 limited partner investment as of
                  March 31, 2001 and as of December 31, 2000


         --       the going concern value per $1,000 limited partner investment

         --       the liquidation value per $1,000 limited partner investment


         --       the ordinary tax loss per $1,000 limited partner investment in
                  year of initial investment

    o    Information about:

         --       the legal opinion for the limited partners

         --       the term of the partnership

    o    The partnership's financial statements, including management's
         discussion and analysis of financial condition and results of
         operations, for the three months ended March 31, 2001

    o    The partnership's financial statements, including management's
         discussion and analysis of financial condition and results of
         operations, for the year ended December 31, 2000


    o    Selected historical financial data for the partnership for the three
         months ended March 31, 2001 and 2000 and the five years ended December
         31, 2000

                                      -1-

   1302
                        PARKER & PARSLEY 89-B CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners(a)                                        $   6,307

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                    $   5,875

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   1,778
USA(a),(b)

Merger Value per $1,000 Limited Partner Investment(b),(c)                                      $  282.79

Merger Value per $1,000 Limited Partner Investment as a Multiple of                                 3.25 times

Distributions for the  past four quarterly distributions including the
distribution in July 2001(b),(c)

Book Value per $1,000 Limited Partner Investment:

     --  as of March 31, 2001(c)                                                               $  165.20

     --  as of December 31, 2000(c)                                                            $  171.00

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  261.84

Liquidation Value per $1,000 Limited Partner Investment(c),(e)                                 $  274.51

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     158
(c),(f)



----------

(a) Stated in thousands.


(b) The merger value for the partnership is equal to the sum of the present
    value of estimated future net revenues from the partnership's estimated oil
    and gas reserves and its net working capital, in each case as of March 31,
    2001, less its pro rata share, based on its reserve value, of the estimated
    expenses and fees of the mergers of all of the partnerships and less the
    cash distribution on or about July 9, 2001, by the partnership to its
    partners.

(c) Interests in some partnerships were sold in units at prices other than
    $1,000. We have presented this information based on a $1,000 initial
    investment for ease of use and comparison among partnerships. You should not
    assume that the amount shown per $1,000 investment is the same as the value
    or amount attributable to a single unit investment.

(d) The going concern value for the partnership is based upon: (1) the sum of
    (A) the estimated net cash flow from the sale of the partnership's reserves
    during a 10-year operating period and (B) the estimated residual value from
    the sale of the partnership's remaining reserves at the end of the operating
    period, in each case using the same pricing and discount rate as in the
    merger value calculation, less (2) partnership level general and
    administrative expenses.

(e) The liquidation value for the partnership is based upon the sale of the
    partnership's reserves at the reserve value, less liquidation expenses which
    are estimated to be the sum of (1) the partnership's pro rata share of the
    merger expenses and fees described in footnote (b) above and (2) 3% of the
    partnership's reserve value. The liquidation expenses represent estimated
    costs to retain an investment banker or broker to sell the assets of the
    partnership and the legal and other closing costs associated with such
    transaction, including the wind-down costs of the partnership.

(f) Your ability to use your distributive share of the partnership's loss to
    offset your other income may have been subject to certain limitations at
    your level as a partner, and you may therefore wish to consult your tax
    advisor to determine the additional value, if any, actually realized by you
    in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

    The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

    The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                     -2-





   1303


                        PARKER & PARSLEY 89-B CONV., L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   1304


                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS



                                                     March 31,     December 31,
                                                       2001            2000
                                                   ------------    ------------
                                                    (Unaudited)
                                                             
                 ASSETS

Current assets:
  Cash                                             $     79,765    $     94,922
  Accounts receivable - oil and gas sales               129,925         134,431
                                                   ------------    ------------
        Total current assets                            209,690         229,353
                                                   ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,317,213       5,314,971
Accumulated depletion                                (4,461,599)     (4,443,011)
                                                   ------------    ------------
        Net oil and gas properties                      855,614         871,960
                                                   ------------    ------------
                                                   $  1,065,304    $  1,101,313
                                                   ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $     12,720    $     11,787

Partners' capital:
  Managing general partner                               10,672          11,042
  Limited partners (6,307 interests)                  1,041,912       1,078,484
                                                   ------------    ------------
                                                      1,052,584       1,089,526
                                                   ------------    ------------
                                                   $  1,065,304    $  1,101,313
                                                   ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   1305



                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                    Three months ended
                                                         March 31,
                                                  -----------------------
                                                     2001         2000
                                                  ----------   ----------
                                                         
Revenues:
  Oil and gas                                     $  242,302   $  198,773
  Interest                                             1,783        1,531
                                                  ----------   ----------
                                                     244,085      200,304
                                                  ----------   ----------
Costs and expenses:
  Oil and gas production                              85,210       82,217
  General and administrative                           8,379        5,963
  Depletion                                           18,588       15,289
                                                  ----------   ----------
                                                     112,177      103,469
                                                  ----------   ----------
Net income                                        $  131,908   $   96,835
                                                  ==========   ==========
Allocation of net income:
  Managing general partner                        $    1,319   $      968
                                                  ==========   ==========
  Limited partners                                $  130,589   $   95,867
                                                  ==========   ==========
Net income per limited partnership interest       $    20.71   $    15.20
                                                  ==========   ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3

   1306



                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                     Managing
                                      general        Limited
                                      partner        partners         Total
                                   ------------    ------------    ------------
                                                          
Balance at January 1, 2001         $     11,042    $  1,078,484    $  1,089,526

    Distributions                        (1,689)       (167,161)       (168,850)

    Net income                            1,319         130,589         131,908
                                   ------------    ------------    ------------

Balance at March 31, 2001          $     10,672    $  1,041,912    $  1,052,584
                                   ============    ============    ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   1307


                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                          Three months ended
                                                               March 31,
                                                       ----------    ----------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $  131,908    $   96,835
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                           18,588        15,289
  Changes in assets and liabilities:
       Accounts receivable                                  4,506       (10,936)
       Accounts payable                                       933         2,358
                                                       ----------    ----------
         Net cash provided by operating activities        155,935       103,546
                                                       ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                      (2,242)       (4,540)

Cash flows used in financing activities:
  Cash distributions to partners                         (168,850)      (90,992)
                                                       ----------    ----------
Net increase (decrease) in cash                           (15,157)        8,014
Cash at beginning of period                                94,922       116,810
                                                       ----------    ----------
Cash  at end of period                                 $   79,765    $  124,824
                                                       ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   1308



                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley 89-B Conv., L.P. (the "Partnership") was organized as a general
partnership in 1989 under the laws of the State of Texas and was converted to a
Delaware limited partnership on May 30, 1990.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 22% to $242,302 for the three
months ended March 31, 2001 as compared to $198,773 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 4,701
barrels of oil, 1,784 barrels of natural gas liquids ("NGLs") and 12,480 mcf of
gas were sold, or 8,565 barrel of oil equivalents ("BOEs"). For the three months

                                        6

   1309



ended March 31, 2000, 5,036 barrels of oil, 2,823 barrels of NGLs and 11,218 mcf
of gas were sold, or 9,729 BOEs.

The average price received per barrel of oil increased $1.28, or 5%, from $27.13
for the three months ended March 31, 2000 to $28.41 for the same period in 2001.
The average price received per barrel of NGLs increased $4.56, or 31%, from
$14.82 for the three months ended March 31, 2000 to $19.38 for the same period
in 2001. The average price received per mcf of gas increased 232% from $1.79
during the three months ended March 31, 2000 to $5.95 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $112,177 for the three months ended March
31, 2001 as compared to $103,469 for the same period in 2000, an increase of
$8,708, or 8%. This increase was due to increases in depletion, production costs
and general and administrative expenses ("G&A").

Production costs were $85,210 for the three months ended March 31, 2001 and
$82,217 for the same period in 2000 resulting in a $2,993 increase, or 4%. The
increase was due to higher production taxes associated with higher oil and gas
prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 41% from $5,963 for the three months ended March 31, 2000 to $8,379
for the same period in 2001 primarily due to a higher percentage of the managing
general partner's G&A being allocated (limited to 3% of oil and gas revenues) as
a result of increased oil and gas revenues and an increase in the accrual for
tax preparation fees.

Depletion was $18,588 for the three months ended March 31, 2001 as compared to
$15,289 for the same period in 2000, an increase of $3,299, or 22%. This
increase was primarily due to downward revisions to proved reserves on several
wells for the three months ended March 31, 2001 as compared to the same period
in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $52,389 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $43,781 and a
reduction of $14,017 in working capital, offset by increases in production costs
of $2,993 and G&A expenses of $2,416. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an



                                        7

   1310


additional $65,914 to oil and gas receipts, offset by $22,133 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $168,850, of which $1,689 was distributed to the managing general partner
and $167,161 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $90,992, of which $910 was distributed
to the managing general partner and $90,082 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.



                                        8


   1311
                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                              FINANCIAL STATEMENTS
                        WITH INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   1312

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 89-B Conv., L.P.
 (A Delaware Limited Partnership):

We have audited the accompanying balance sheets of Parker & Parsley 89-B Conv.,
L.P. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 89-B Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001

                                       2
   1313


                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                     2000          1999
                                                                   --------      ---------
                                                                         
              ASSETS
              ------
Current assets:
  Cash                                                           $    94,922   $   116,810
  Accounts receivable - oil and gas sales                            134,431        73,499
                                                                  ----------    ----------

         Total current assets                                        229,353       190,309
                                                                  ----------    ----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                             5,314,971     5,304,537
Accumulated depletion                                             (4,443,011)  (4,349,082)
                                                                  ----------    ----------

         Net oil and gas properties                                  871,960       955,455
                                                                  ----------    ----------

                                                                 $ 1,101,313   $ 1,145,764
                                                                  ==========    ==========


LIABILITIES AND PARTNERS' CAPITAL
---------------------------------
Current liabilities:
  Accounts payable - affiliate                                   $    11,787   $    15,267

Partners' capital:
  Managing general partner                                            11,042        11,451
  Limited partners (6,307 interests)                               1,078,484     1,119,046
                                                                  ----------    ----------

                                                                   1,089,526     1,130,497
                                                                  ----------    ----------

                                                                 $ 1,101,313   $ 1,145,764
                                                                  ==========    ==========


   The accompanying notes are an integral part of these financial statements.

                                        3
   1314


                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31







                                                      2000           1999          1998
                                                     -------       --------       -------

                                                                       
Revenues:
  Oil and gas                                      $ 873,058     $  542,232     $ 471,148
  Interest                                             8,377          4,914         5,410
  Gain on disposition of assets                          -              354           108
                                                     -------       --------       -------

                                                     881,435        547,500       476,666
                                                     -------       --------       -------

Costs and expenses:
  Oil and gas production                             326,082        305,897       322,354
  General and administrative                          28,155         20,352        16,076
  Impairment of oil and gas properties                27,748            -         262,396
  Depletion                                           66,181         99,538       241,875
                                                     -------       --------       -------

                                                     448,166        425,787       842,701
                                                     -------       --------       -------

Net income (loss)                                  $ 433,269     $  121,713     $(366,035)
                                                    ========      =========      ========

Allocation of net income (loss):
  Managing general partner                         $   4,333     $    1,217     $  (3,660)
                                                    ========      =========      ========

  Limited partners                                 $ 428,936     $  120,496     $(362,375)
                                                    ========      =========      ========

Net income (loss) per limited partnership
  interest                                         $   68.01     $    19.11     $  (57.46)
                                                    ========      =========      ========


   The accompanying notes are an integral part of these financial statements.

                                       4
   1315
                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                     Managing
                                                     general       Limited
                                                     partner       partners         Total
                                                   ------------- -------------- -----------


                                                                       
Partners' capital at January 1, 1998               $ 17,202      $1,688,386     $1,705,588

  Distributions                                      (1,765)       (174,700)      (176,465)

  Net loss                                           (3,660)       (362,375)      (366,035)
                                                     ------        --------       --------

Partners' capital at December 31, 1998               11,777       1,151,311      1,163,088

  Distributions                                      (1,543)       (152,761)      (154,304)

  Net income                                          1,217         120,496        121,713
                                                     ------        --------        -------

Partners' capital at December 31, 1999               11,451       1,119,046      1,130,497

  Distributions                                      (4,742)       (469,498)      (474,240)

  Net income                                          4,333         428,936        433,269
                                                     ------        --------        -------

Partners' capital at December 31, 2000             $ 11,042      $1,078,484     $1,089,526
                                                    =======       =========      =========


   The accompanying notes are an integral part of these financial statements.

                                       5
   1316


                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                       2000         1999           1998
                                                     -------       -------        -------

                                                                       
Cash flows from operations:
  Net income (loss)                                $ 433,269     $ 121,713      $(366,035)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
     Impairment of oil and gas properties             27,748           -          262,396
     Depletion                                        66,181        99,538        241,875
     Gain on disposition of assets                       -            (354)          (108)
  Changes in assets and liabilities:
     Accounts receivable                             (60,932)      (20,669)        43,290
     Accounts payable                                 (3,480)        2,834         (6,986)
                                                     -------       -------        -------

        Net cash provided by operating activities    462,786       203,062        174,432
                                                     -------       -------        -------

Cash flows from investing activities:
  Additions to oil and gas properties                (10,434)       (7,556)       (10,801)
  Proceeds from asset dispositions                       -             354            108
                                                     -------       -------        -------

        Net cash used in investing activities        (10,434)       (7,202)       (10,693)
                                                     -------       -------        -------

Cash flows used in financing activities:
  Cash distributions to partners                    (474,240)     (154,304)      (176,465)
                                                    --------      --------       --------

Net increase (decrease) in cash                      (21,888)       41,556        (12,726)
Cash at beginning of year                            116,810        75,254         87,980
                                                     -------       -------        -------

Cash at end of year                                $  94,922     $ 116,810      $  75,254
                                                    ========      ========       ========


   The accompanying notes are an integral part of these financial statements.

                                       6
   1317


                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 89-B Conv., L.P. (the "Partnership") was organized as a
general partnership in 1989 under the laws of the State of Texas and was
converted to a Delaware limited partnership on May 30, 1990. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121. "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

                                       7
   1318

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.       IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $27,748 and $262,396
related to its proved oil and gas properties during 2000 and 1998, respectively.

                                       8
   1319

NOTE 4.       INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $191,325 greater than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                          2000          1999           1998
                                                        -------       -------        -------

                                                                          
  Net income (loss) per statements of operations      $ 433,269     $ 121,713      $(366,035)
  Impairment of oil and gas properties for financial
    reporting purposes                                   27,748           -          262,396
  Depletion and depreciation provisions for tax
    reporting purposes less than amounts for
    financial reporting purposes                         57,991        91,381        226,609
  Other, net                                             (1,014)       (2,514)         2,725
                                                        -------       -------        -------

        Net income per Federal income tax returns     $ 517,994     $ 210,580      $ 125,695
                                                       ========      ========       ========


NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                    --------      --------       --------

                                                                       
    Development costs                              $  10,434     $   7,556      $  10,801
                                                    ========      ========       ========


      Capitalized oil and gas properties consist of the following:



                                                                      2000          1999
                                                                   ---------      ---------
                                                                          
Proved properties:
      Property acquisition costs                                 $   171,441    $   171,441
      Completed wells and equipment                                5,143,530      5,133,096
                                                                  ----------     ----------

                                                                   5,314,971      5,304,537
    Accumulated depletion                                         (4,443,011)    (4,349,082)
                                                                  -----------    ----------

           Net oil and gas properties                            $   871,960    $   955,455
                                                                  ==========     ==========


                                       9
   1320


NOTE 6.       RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                          2000          1999           1998
                                                       ---------     ---------      ---------

                                                                           
      Payment of lease operating and supervision
        charges in accordance with standard industry
        operating agreements                           $ 133,513     $ 129,059      $ 124,312
      Reimbursement of general and administrative
        expenses                                       $  25,658     $  16,168      $  14,082


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and P&P Employees 89-B Conv., L.P. ("EMPL"), Parker & Parsley 89-B, L.P. and the
Partnership (the "Partnerships") are parties to the Program agreement. EMPL is a
limited partnership organized for the benefit of certain employees of Pioneer
USA. EMPL was merged with Pioneer USA on December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                            Pioneer USA (1)   Partnerships (2)
                                                            ---------------   ----------------
                                                                           
Revenues:
  Proceeds from disposition of depreciable
    and depletable properties -
      First three years                                        14.141414%        85.858586%
      After first three years                                  19.191919%        80.808081%
  All other revenues -
      First three years                                        14.141414%        85.858586%
      After first three years                                  19.191919%        80.808081%

Costs and expenses:
  Lease acquisition costs, drilling and completion
    costs and all other costs                                   9.090909%        90.909091%
  Operating costs, reporting and legal expenses
   and general and administrative expenses -
      First three years                                        14.141414%        85.858586%
      After first three years                                  19.191919%        80.808081%


      (1)   Excludes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 20 limited partner interests
            owned by Pioneer USA.

      (2)   The allocation between the Partnership and Parker & Parsley 89-B,
            L.P. is 47.578455% and 52.421545%, respectively.

NOTE 7.       OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       10
   1321



                                                              Oil and NGLs         Gas
                                                                 (bbls)            (mcf)
                                                              ------------      ----------

                                                                          
    Net proved reserves at January 1, 1998                        471,441          734,987
    Revisions                                                    (202,204)        (246,962)
    Production                                                    (35,481)         (52,345)
                                                               ----------       ----------

    Net proved reserves at December 31, 1998                      233,756          435,680
    Revisions                                                     267,905          413,961
    Production                                                    (32,585)         (46,681)
                                                               ----------       ----------

    Net proved reserves at December 31, 1999                      469,076          802,960
    Revisions                                                       1,942         (157,459)
    Production                                                    (30,959)         (42,179)
                                                               ----------       ----------

    Net proved reserves at December 31, 2000                      440,059          603,322
                                                               ==========       ==========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.35 per barrel of NGLs and $7.90 per mcf of gas,
discounted at 10% was approximately $3,414,000 and undiscounted was $6,785,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                For the years ended December 31,
                                                             --------------------------------------
                                                                 2000          1999         1998
                                                             -----------   -----------  -----------
                                                                         (in thousands)
                                                                               
Oil and gas producing activities:
  Future cash inflows                                        $   14,354    $   11,715   $    2,608
  Future production costs                                        (7,569)       (6,914)      (1,962)
                                                               --------      --------     --------

                                                                  6,785         4,801          646
  10% annual discount factor                                     (3,371)       (2,230)        (224)
                                                               --------      --------     --------

  Standardized measure of discounted future net cash flows   $    3,414    $   2,571    $      422
                                                              =========     ========     =========


                                       11
   1322



                                                          For the years ended December 31,
                                                       --------------------------------------
                                                          2000          1999         1998
                                                       -----------   -----------  -----------
                                                                  (in thousands)
                                                                        
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (547)  $      (236)  $     (149)
    Net changes in prices and production costs              1,522         1,145       (1,146)
    Revisions of previous quantity estimates                 (163)        1,753         (282)
    Accretion of discount                                     257            42          189
    Changes in production rates, timing and other            (226)         (555)         (76)
                                                         --------     ---------     --------

    Change in present value of future net revenues            843         2,149       (1,464)
                                                         --------     ---------     --------

    Balance, beginning of year                              2,571           422        1,886
                                                         --------     ---------     --------

    Balance, end of year                               $    3,414   $     2,571   $      422
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

  The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:



                                                         2000         1999          1998
                                                       --------     --------      --------

                                                                         
          Plains Marketing, L.P.                          55%           51%            -
          Genesis Crude Oil, L.P.                          -            -             59%
          Western Gas Resources, Inc.                      4%            6%           26%


      At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $37,745 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.       PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
Partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the limited partnership agreement, the managing general partner pays
      1% of the Partnership's acquisition, drilling and completion costs and 1%
      of its operating, general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of
      undistributed profits.

                                       12
   1323

      Initial capital contributions - The partners entered into subscription
      agreements for aggregate capital contributions of $6,307,000. The managing
      general partner is required to contribute amounts equal to 1% of initial
      Partnership capital less commission and organization and offering costs
      allocated to the limited partners and to contribute amounts necessary to
      pay costs and expenses allocated to it under the Partnership agreement to
      the extent its share of revenues does not cover such costs.

                                       13
   1324
                        PARKER & PARSLEY 89-B CONV., L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
  RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 61% to $873,058 for 2000 as
compared to $542,232 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 19,708
barrels of oil, 11,251 barrels of natural gas liquids ("NGLs") and 42,179 mcf of
gas were sold, or 37,989 barrel of oil equivalents ("BOEs"). In 1999, 20,322
barrels of oil, 12,263 barrels of NGLs and 46,681 mcf of gas were sold, or
40,365 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.25, or 72%, from
$16.96 in 1999 to $29.21 in 2000. The average price received per barrel of NGLs
increased $5.99, or 63%, from $9.57 in 1999 to $15.56 in 2000. The average price
received per mcf of gas increased 69% from $1.72 in 1999 to $2.90 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $448,166 as compared to $425,787
in 1999, an increase of $22,379, or 5%. The increase was due to increases in the
impairment of oil and gas properties, production costs and general and
administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $326,082 in 2000 and $305,897 in 1999, resulting in a
$20,185 increase, or 7%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices, offset by a decline in well
maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
38% from $20,352 in 1999 to $28,155 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $25,658 in 2000 and $16,168 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partners. The method
of allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $27,748 related to its oil and gas properties during 2000.

Depletion was $66,181 in 2000 as compared to $99,538 in 1999, representing a
decrease of $33,357, or 34%. This decrease was primarily due to an 8,572 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.


   1325

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 15% to $542,232 from
$471,148 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 20,322 barrels of oil,
12,263 barrels of NGLs and 46,681 mcf of gas were sold, or 40,365 BOEs. In 1998,
22,378 barrels of oil, 13,103 barrels of NGLs and 52,345 mcf of gas were sold,
or 44,205 BOEs.

The average price received per barrel of oil increased $3.70, or 28%, from
$13.26 in 1998 to $16.96 in 1999. The average price received per barrel of NGLs
increased $2.63, or 38%, from $6.94 in 1998 to $9.57 in 1999. The average price
received per mcf of gas increased 8% from $1.60 in 1998 to $1.72 in 1999.

Total costs and expenses decreased in 1999 to $425,787 as compared to $842,701
in 1998, a decrease of $416,914, or 49%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $305,897 in 1999 and $322,354 in 1998, resulting in a
$16,457 decrease, or 5%. The decrease was due to declines in ad valorem taxes
and well maintenance costs.

During this period, G&A increased 27% from $16,076 in 1998 to $20,352 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $16,168 in
1999 and $14,082 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $262,396 related to its
oil and gas properties during 1998.

Depletion was $99,538 in 1999 compared to $241,875 in 1998, representing a
decrease of $142,337, or 59%. This decrease was the result of an increase in
proved reserves of 173,770 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $259,724 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $334,289, offset by increases in production costs paid
of $20,185, G&A expenses paid of $7,803 and working capital of $46,577. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $381,025 to oil and gas receipts,
offset by $46,736 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices, offset by a decline in well
maintenance costs. The increase in G&A was primarily due to higher percentage of
the managing general partner's G&A being allocated (limited


   1326

to 3% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $474,240, of which $4,742 was
distributed to the managing general partner and $469,498 to the limited
partners. In 1999, cash distributions to the partners were $154,304, of which
$1,543 was distributed to the managing general partner and $152,761 to the
limited partners.

   1327



                        PARKER & PARSLEY 89-B CONV., L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.




                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          

Operating results:
  Oil and gas sales                $          $  198,773   $  873,058   $  542,232   $  471,148   $  718,293   $  849,156
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   27,748   $       --   $  262,396   $  330,848   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   96,835   $  433,269   $  121,713   $ (366,035)  $ (122,936)  $  342,846
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      968   $    4,333   $    1,217   $   (3,660)  $   (1,229)  $    3,428
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   95,867   $  428,936   $  120,496   $ (362,375)  $ (121,707)  $  339,418
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    15.20   $    68.01   $    19.11   $   (57.46)  $   (19.30)  $    53.82
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    14.28   $    74.44   $    24.22   $    27.70   $    62.96   $    61.29
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $1,153,965   $1,101,313   $1,145,764   $1,175,521   $1,725,007   $2,246,482
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1328
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 89-B, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                              --------------------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                              --------------------


     This document contains important information specific to Parker & Parsley
89-B, L.P., and supplements the proxy statement/prospectus dated       , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc.,
by which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 89-B, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31 , 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-
   1329
                           PARKER & PARSLEY 89-B, L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners  (a)                                     $    6,949

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                 $    6,473

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $    1,942
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                  $   282.39

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.22 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                   $   165.32

        --        as of December 31, 2000  (c)                                                $   171.15

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                           $   261.46

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                             $   274.12

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial                    $      158
Investment  (c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   1330

                           PARKER & PARSLEY 89-B, L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   1331



                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS





                                                   March 31,     December 31,
                                                     2001            2000
                                                 ------------    ------------
                                                 (Unaudited)
                                                           
                 ASSETS

Current assets:
  Cash                                           $     88,720    $    105,641
  Accounts receivable - oil and gas sales             143,094         148,020
                                                 ------------    ------------
        Total current assets                          231,814         253,661
                                                 ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              5,858,274       5,855,803
Accumulated depletion                              (4,915,389)     (4,894,889)
                                                 ------------    ------------
        Net oil and gas properties                    942,885         960,914
                                                 ------------    ------------
                                                 $  1,174,699    $  1,214,575
                                                 ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $     14,025    $     12,985

Partners' capital:
  Managing general partner                             11,847          12,256
  Limited partners (6,949 interests)                1,148,827       1,189,334
                                                 ------------    ------------
                                                    1,160,674       1,201,590
                                                 ------------    ------------
                                                 $  1,174,699    $  1,214,575
                                                 ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   1332

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  266,742   $  218,705
  Interest                                         1,957        1,700
                                              ----------   ----------
                                                 268,699      220,405
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                          93,860       90,560
  General and administrative                       9,217        6,561
  Depletion                                       20,500       16,845
                                              ----------   ----------
                                                 123,577      113,966
                                              ----------   ----------
Net income                                    $  145,122   $  106,439
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $    1,451   $    1,064
                                              ==========   ==========
  Limited partners                            $  143,671   $  105,375
                                              ==========   ==========
Net income per limited partnership interest   $    20.68   $    15.16
                                              ==========   ==========




       The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.



                                        3
   1333

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                Managing
                                general        Limited
                                partner        partners          Total
                             ------------    ------------    ------------
                                                    
Balance at January 1, 2001   $     12,256    $  1,189,334    $  1,201,590

    Distributions                  (1,860)       (184,178)       (186,038)

    Net income                      1,451         143,671         145,122
                             ------------    ------------    ------------

Balance at March 31, 2001    $     11,847    $  1,148,827    $  1,160,674
                             ============    ============    ============




       The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.



                                        4
   1334

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                        Three months ended
                                                             March 31,
                                                     --------------------------
                                                        2001          2000
                                                     ----------    ----------
                                                             
Cash flows from operating activities:
  Net income                                         $  145,122    $  106,439
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         20,500        16,845
  Changes in assets and liabilities:
       Accounts receivable                                4,926       (11,979)
       Accounts payable                                   1,040         2,590
                                                     ----------    ----------

         Net cash provided by operating activities      171,588       113,895
                                                     ----------    ----------

Cash flows used in investing activities:
  Additions to oil and gas properties                    (2,471)       (5,001)

Cash flows used in financing activities:
  Cash distributions to partners                       (186,038)     (100,255)
                                                     ----------    ----------

Net increase (decrease) in cash                         (16,921)        8,639
Cash at beginning of period                             105,641       130,083
                                                     ----------    ----------

Cash at end of period                                $   88,720    $  138,722
                                                     ==========    ==========




       The financial information included herein has been prepared by the
   managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.



                                        5
   1335



                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.  Organization and nature of operations

Parker & Parsley 89-B, L.P. (the "Partnership") is a limited partnership
organized in 1989 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 22% to $266,742 for the three
months ended March 31, 2001 as compared to $218,705 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 5,173
barrels of oil, 1,967 barrels of natural gas liquids ("NGLs") and 13,738 mcf of
gas were sold, or 9,430 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 5,544 barrels of oil, 3,112 barrels of NGLs and 12,352 mcf
of gas were sold, or 10,715 BOEs.



                                        6
   1336

The average price received per barrel of oil increased $1.28, or 5%, from $27.13
for the three months ended March 31, 2000 to $28.41 for the same period in 2001.
The average price received per barrel of NGLs increased $4.56, or 31%, from
$14.82 for the three months ended March 31, 2000 to $19.38 for the same period
in 2001. The average price received per mcf of gas increased 232% from $1.79
during the three months ended March 31, 2000 to $5.95 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $123,577 for the three months ended March
31, 2001 as compared to $113,966 for the same period in 2000, an increase of
$9,611, or 8%. This increase was due to increases in depletion, production costs
and general and administrative expenses ("G&A").

Production costs were $93,860 for the three months ended March 31, 2001 and
$90,560 for the same period in 2000 resulting in a $3,300 increase, or 4%. The
increase was due to higher production taxes associated with higher oil and gas
prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 40% from $6,561 for the three months ended March 31, 2000 to $9,217
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $20,500 for the three months ended March 31, 2001 compared to
$16,845 for the same period in 2000, an increase of $3,655, or 22%. This
increase was primarily due to downward revisions to proved reserves on several
wells for the three months ended March 31, 2001 as compared to the same period
in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $57,693 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $48,294 and a
reduction of $15,355 in working capital, offset by increases in production costs
of $3,300 and G&A expenses of $2,656. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $72,787 to oil and gas receipts, offset by $24,493 resulting from the
decline in production during 2001 as compared to the same period in 2000. The



                                        7
   1337

increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $186,038, of which $1,860 was distributed to the managing general partner
and $184,178 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $100,255, of which $1,003 was
distributed to the managing general partner and $99,252 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   1338
                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   1339

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 89-B, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 89-B, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 89-B, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                       2
   1340

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                   2000             1999
                                               -----------      -----------
                                                          
              ASSETS
              ------

Current assets:
  Cash                                         $   105,641      $   130,083
  Accounts receivable - oil and gas sales          148,020           80,988
                                               -----------      -----------

    Total current assets                           253,661          211,071
                                               -----------      -----------

Oil and gas properties - at cost, based on
  the successful efforts accounting method       5,855,803        5,844,308
Accumulated depletion                           (4,894,889)      (4,791,400)
                                               -----------      -----------

        Net oil and gas properties                 960,914        1,052,908
                                               -----------      -----------

                                               $ 1,214,575      $ 1,263,979
                                               ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                 $    12,985      $    16,819

Partners' capital:
  Managing general partner                          12,256           12,712
  Limited partners (6,949 interests)             1,189,334        1,234,448
                                               -----------      -----------

                                                 1,201,590        1,247,160
                                               -----------      -----------

                                               $ 1,214,575      $ 1,263,979
                                               ===========      ===========


   The accompanying notes are an integral part of these financial statements.


                                       3
   1341

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                          2000          1999          1998
                                                       ---------     ---------     ---------

                                                                          
Revenues:
  Oil and gas                                          $ 961,197     $ 597,130     $ 518,801
  Interest                                                 9,481         5,469         6,043
  Gain on disposition of assets                               --           390           119
                                                       ---------     ---------     ---------

                                                         970,678       602,989       524,963
                                                       ---------     ---------     ---------

Costs and expenses:
  Oil and gas production                                 359,243       337,025       355,148
  General and administrative                              31,002        22,369        17,625
  Impairment of oil and gas properties                    30,586            --       289,124
  Depletion                                               72,903       109,755       266,451
                                                       ---------     ---------     ---------

                                                         493,734       469,149       928,348
                                                       ---------     ---------     ---------

Net income (loss)                                      $ 476,944     $ 133,840     $(403,385)
                                                       =========     =========     =========

Allocation of net income (loss):
  Managing general partner                             $   4,769     $   1,338     $  (4,034)
                                                       =========     =========     =========

  Limited partners                                     $ 472,175     $ 132,502     $(399,351)
                                                       =========     =========     =========

Net income (loss) per limited partnership interest     $   67.95     $   19.07     $  (57.47)
                                                       =========     =========     =========



   The accompanying notes are an integral part of these financial statements.


                                       4
   1342

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                             Managing
                                             general          Limited
                                             partner          partners           Total
                                           -----------      -----------      -----------

                                                                    
Partners' capital at January 1, 1998       $    19,053      $ 1,862,101      $ 1,881,154

  Distributions                                 (1,945)        (192,484)        (194,429)

  Net loss                                      (4,034)        (399,351)        (403,385)
                                           -----------      -----------      -----------

Partners' capital at December 31, 1998          13,074        1,270,266        1,283,340

  Distributions                                 (1,700)        (168,320)        (170,020)

  Net income                                     1,338          132,502          133,840
                                           -----------      -----------      -----------

Partners' capital at December 31, 1999          12,712        1,234,448        1,247,160

  Distributions                                 (5,225)        (517,289)        (522,514)

  Net income                                     4,769          472,175          476,944
                                           -----------      -----------      -----------

Partners' capital at December 31, 2000     $    12,256      $ 1,189,334      $ 1,201,590
                                           ===========      ===========      ===========


   The accompanying notes are an integral part of these financial statements.


                                       5
   1343

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                          2000           1999           1998
                                                       ---------      ---------      ---------

                                                                            
Cash flows from operating activities:
  Net income (loss)                                    $ 476,944      $ 133,840      $(403,385)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties                30,586             --        289,124
      Depletion                                           72,903        109,755        266,451
      Gain on disposition of assets                           --           (390)          (119)
  Changes in assets and liabilities:
      Accounts receivable                                (67,032)       (22,818)        47,684
      Accounts payable                                    (3,834)         2,839         (7,697)
                                                       ---------      ---------      ---------

         Net cash provided by operating activities       509,567        223,226        192,058
                                                       ---------      ---------      ---------

Cash flows from investing activities:
  Additions to oil and gas properties                    (11,495)        (8,325)       (11,900)
  Proceeds from dispositions of assets                        --            390            119
                                                       ---------      ---------      ---------

         Net cash used in investing activities           (11,495)        (7,935)       (11,781)
                                                       ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                        (522,514)      (170,020)      (194,429)
                                                       ---------      ---------      ---------

Net increase (decrease) in cash                          (24,442)        45,271        (14,152)
Cash at beginning of year                                130,083         84,812         98,964
                                                       ---------      ---------      ---------

Cash at end of year                                    $ 105,641      $ 130,083      $  84,812
                                                       =========      =========      =========


   The accompanying notes are an integral part of these financial statements.


                                       6
   1344

                           PARKER & PARSLEY 89-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 89-B, L.P. (the "Partnership") is a limited partnership
organized in 1989 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.


                                       7
   1345

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $30,586 and $289,124
related to its proved oil and gas properties during 2000 and 1998, respectively.


                                       8
   1346

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $211,364 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                          2000           1999           1998
                                                       ---------      ---------      ---------

                                                                            
Net income (loss) per statements of operations         $ 476,944      $ 133,840      $(403,385)
Impairment of oil and gas properties for financial
 reporting purposes                                       30,586             --        289,124
Depletion and depreciation provisions for tax
 reporting purposes less than amounts deducted
 for financial reporting purposes                         63,879        100,769        254,734
Other, net                                                (1,322)        (3,050)         3,282
                                                       ---------      ---------      ---------

       Net income per Federal income tax returns       $ 570,087      $ 231,559      $ 143,755
                                                       =========      =========      =========


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the net costs incurred, whether
capitalized or expensed, related to the Partnership's oil and gas producing
activities for the years ended December 31:



                         2000          1999        1998
                      ---------     ---------     -------

                                         
Development costs     $  11,495     $   8,325     $11,900
                      =========     =========     =======


        Capitalized oil and gas properties consist of the following:



                                       2000             1999
                                    -----------      -----------
                                               
Proved properties:
  Property acquisition costs        $   188,868      $   188,868
  Completed wells and equipment       5,666,935        5,655,440
                                    -----------      -----------

                                      5,855,803        5,844,308
Accumulated depletion                (4,894,889)      (4,791,400)
                                    -----------      -----------

     Net oil and gas properties     $   960,914      $ 1,052,908
                                    ===========      ===========



                                       9
   1347

NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                  2000         1999         1998
                                                --------     --------     --------
                                                                 
Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                 $147,103     $142,197     $136,965

Reimbursement of general and administrative
  expenses                                      $ 28,269     $ 17,812     $ 15,438


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 89-B Conv., L.P. ("EMPL") Parker & Parsley 89-B Conv., L.P. and
the Partnership (the "Partnerships") are parties to the Program agreement. EMPL
is a limited partnership organized for the benefit of certain employees of
Pioneer USA. EMPL was merged with Pioneer USA on December 28, 2000.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:



                                                             Pioneer USA (1)   Partnerships (2)
                                                             ---------------   ----------------
                                                                         
Revenues:
   Proceeds from disposition of depreciable and
     depletable properties -
       First three years                                       14.141414%       85.858586%
       After first three years                                 19.191919%       80.808081%
   All other revenues -
       First three years                                       14.141414%       85.858586%
       After first three years                                 19.191919%       80.808081%
Costs and expenses:
   Lease acquisition costs, drilling and completion
     costs and all other costs                                  9.090909%       90.909091%
   Operating costs, reporting and legal expenses and
     general and administrative expenses -
       First three years                                       14.141414%       85.858586%
       After first three years                                 19.191919%       80.808081%


        (1) Excludes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 72 limited partner interests
            owned by Pioneer USA.

        (2) The allocation between the Partnership and Parker & Parsley 89-B
            Conv., L.P. is 52.421545% and 47.578455%, respectively.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.


                                       10
   1348



                                              Oil and NGLs          Gas
                                                 (bbls)            (mcf)
                                              ------------       --------
                                                           
Net proved reserves at January 1, 1998           519,501          809,915
Revisions                                       (222,853)        (272,177)
Production                                       (39,063)         (57,643)
                                                --------         --------

Net proved reserves at December 31, 1998         257,585          480,095
Revisions                                        295,189          456,122
Production                                       (35,879)         (51,400)
                                                --------         --------

Net proved reserves at December 31, 1999         516,895          884,817
Revisions                                          1,443         (174,232)
Production                                       (34,089)         (46,454)
                                                --------         --------

Net proved reserves at December 31, 2000         484,249          664,131
                                                ========         ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.35 per barrel of NGLs and $7.90 per mcf of gas,
discounted at 10% was approximately $3,756,000 and undiscounted was $7,461,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.


                                       11
   1349



                                                                 For the years ended December 31,
                                                               ------------------------------------
                                                                 2000          1999          1998
                                                               --------      --------      --------
                                                                          (in thousands)
                                                                                  
Oil and gas producing activities:
  Future cash inflows                                          $ 15,796      $ 12,909      $  2,874
  Future production costs                                        (8,335)       (7,619)       (2,162)
                                                               --------      --------      --------

                                                                  7,461         5,290           712
  10% annual discount factor                                     (3,705)       (2,457)         (247)
                                                               --------      --------      --------

  Standardized measure of discounted future net cash flows     $  3,756      $  2,833      $    465
                                                               ========      ========      ========




                                                      For the years ended December 31,
                                                     ---------------------------------
                                                      2000         1999         1998
                                                     -------      -------      -------
                                                              (in thousands)
                                                                      
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs         $  (602)     $  (260)     $  (163)
  Net changes in prices and production costs           1,674        1,262       (1,263)
  Revisions of previous quantity estimates              (185)       1,931         (311)
  Accretion of discount                                  283           47          208
  Changes in production rates, timing and other         (247)        (612)         (84)
                                                     -------      -------      -------

  Change in present value of future net revenues         923        2,368       (1,613)
                                                     -------      -------      -------

  Balance, beginning of year                           2,833          465        2,078
                                                     -------      -------      -------

  Balance, end of year                               $ 3,756      $ 2,833      $   465
                                                     =======      =======      =======


NOTE 8. MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                        2000    1999    1998
                                        ----    ----    ----
                                               
         Plains Marketing, L.P.          55%     51%      -
         Genesis Crude Oil, L.P.          -       -      59%
         Western Gas Resources, Inc.      4%      6%     26%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $41,588 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.


NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:

          Managing general partner - The managing general partner of the
          Partnership is Pioneer USA. Pioneer USA has the power and authority to
          manage, control and administer all


                                       12
   1350

          Program and Partnership affairs. As managing general partner and
          operator of the Partnership's properties, all production expenses are
          incurred by Pioneer USA and billed to the Partnership. The majority of
          the Partnership's oil and gas revenues are received directly by the
          Partnership, however, a portion of the oil and gas revenue is
          initially received by Pioneer USA prior to being paid to the
          Partnership. Under the limited partnership agreement, the managing
          general partner pays 1% of the Partnership's acquisition, drilling and
          completion costs and 1% of its operating and general and
          administrative expenses. In return, it is allocated 1% of the
          Partnership's revenues.

             Limited partner liability - The maximum amount of liability of any
             limited partner is the total contributions of such partner plus his
             share of any undistributed profits.

             Initial capital contributions - The limited partners entered into
             subscription agreements for aggregate capital contributions of
             $6,949,000. The managing general partner is required to contribute
             amounts equal to 1% of initial Partnership capital less commission
             and offering expenses allocated to the limited partners and to
             contribute amounts necessary to pay costs and expenses allocated to
             it under the Partnership agreement to the extent its share of
             revenues does not cover such costs.


                                       13

   1351
                           PARKER & PARSLEY 89-B, L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 61% to $961,197 for 2000 as
compared to $597,130 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 21,703
barrels of oil, 12,386 barrels of natural gas liquids ("NGLs") and 46,454 mcf of
gas were sold, or 41,831 barrel of oil equivalents ("BOEs"). In 1999, 22,376
barrels of oil, 13,503 barrels of NGLs and 51,400 mcf of gas were sold, or
44,446 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.25, or 72%, from
$16.96 in 1999 to $29.21 in 2000. The average price received per barrel of NGLs
increased $5.99, or 63%, from $9.57 in 1999 to $15.56 in 2000. The average price
received per mcf of gas increased 69% from $1.72 in 1999 to $2.90 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $493,734 as compared to $469,149
in 1999, an increase of $24,585, or 5%. The increase was due to increases in the
impairment of oil and gas properties, production costs and general and
administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $359,243 in 2000 and $337,025 in 1999, resulting in a
$22,218 increase, or 7%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices, offset by a decline in well
maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
39% from $22,369 in 1999 to $31,002 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $28,269 in 2000 and $17,812 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $30,586 related to its oil and gas properties during 2000.

Depletion was $72,903 in 2000 as compared to $109,755 in 1999, representing a
decrease of $36,852, or 34%. This decrease was primarily due to an 8,955 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.


   1352

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 15% to $597,130 from
$518,801 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 22,376 barrels of oil,
13,503 barrels of NGLs and 51,400 mcf of gas were sold, or 44,446 BOEs. In 1998,
24,633 barrels of oil, 14,430 barrels of NGLs and 57,643 mcf of gas were sold,
or 48,670 BOEs.

The average price received per barrel of oil increased $3.70, or 28%, from
$13.26 in 1998 to $16.96 in 1999. The average price received per barrel of NGLs
increased $2.63, or 38%, from $6.94 in 1998 to $9.57 in 1999. The average price
received per mcf of gas increased 8% from $1.60 in 1998 to $1.72 in 1999.

Total costs and expenses decreased in 1999 to $469,149 as compared to $928,348
in 1998, a decrease of $459,199, or 49%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $337,025 in 1999 and $355,148 in 1998, resulting in an
$18,123 decrease, or 5%. The decrease was due to reductions in ad valorem taxes
and well maintenance costs.

During this period, G&A increased 27% from $17,625 in 1998 to $22,369 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $17,812 in
1999 and $15,438 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $289,124 related to its
oil and gas properties during 1998.

Depletion was $109,755 in 1999 compared to $266,451 in 1998, representing a
decrease of $156,696, or 59%. This decrease was the result of an increase in
proved reserves of 191,467 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $286,341 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $368,079, offset by increases in production costs paid
of $22,218, G&A expenses paid of $8,633 and working capital of $50,887. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $419,447 to oil and gas receipts,
offset by $51,368 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices, offset by a decline in well
maintenance costs. The increase in G&A was primarily due to higher percentage of
the managing general partner's G&A being allocated (limited


   1353

to 3% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on several oil and gas properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $522,514, of which $5,225 was
distributed to the managing general partner and $517,289 to the limited
partners. In 1999, cash distributions to the partners were $170,020, of which
$1,700 was distributed to the managing general partner and $168,320 to the
limited partners.

   1354



                           PARKER & PARSLEY 89-B, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  218,705   $  961,197   $  597,130   $  518,801   $  791,004   $  935,268
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   30,586   $       --   $  289,124   $  364,625   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  106,439   $  476,944   $  133,840   $ (403,385)  $ (135,918)  $  377,397
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $    1,064   $    4,769   $    1,338   $   (4,034)  $   (1,359)  $    3,774
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  105,375   $  472,175   $  132,502   $ (399,351)  $ (134,559)  $  373,623
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    15.16   $    67.95   $    19.07   $   (57.47)  $   (19.36)  $    53.77
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    14.28   $    74.44   $    24.22   $    27.70   $    62.96   $    61.30
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $1,272,753   $1,214,575   $1,263,979   $1,297,320   $1,902,831   $2,477,410
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1355

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

              PROXY STATEMENT/PROSPECTUS DATED        , 2001

                                   ----------

               THE DATE OF THIS SUPPLEMENT IS        , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
Private Investment 89, L.P., and supplements the proxy statement/prospectus
dated           , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at a
special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley Private Investment 89, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   1356

                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                      
Aggregate Initial Investment by the Limited Partners(a)                                                  $      7,060

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                              $      5,651

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)    $      1,900

Merger Value per $1,000 Limited Partner Investment(b), (c)                                               $     270.69

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                            3.93 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                      $     148.20

      --    as of December 31, 2000(c)                                                                   $     150.75

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                        $     252.15

Liquidation Value per $1,000 Limited Partner Investment(c). (e)                                          $     262.68

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)            $        165



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   1357

                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001



   1358



                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS





                                                      March 31,       December 31,
                                                        2001             2000
                                                    -----------       -----------
                                                    (Unaudited)
                                                              
                 ASSETS


Current assets:
  Cash                                              $    60,477       $   101,600
  Accounts receivable - oil and gas sales               150,393           118,399
                                                    -----------       -----------
        Total current assets                            210,870           219,999
                                                    -----------       -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,238,408         5,223,723
Accumulated depletion                                (4,372,561)       (4,351,220)
                                                    -----------       -----------
        Net oil and gas properties                      865,847           872,503
                                                    -----------       -----------
                                                    $ 1,076,717       $ 1,092,502
                                                    ===========       ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $    17,848       $    15,443

Partners' capital:
  Managing general partner                               12,585            12,767
  Limited partners (176.5 interests)                  1,046,284         1,064,292
                                                    -----------       -----------
                                                      1,058,869         1,077,059
                                                    -----------       -----------
                                                    $ 1,076,717       $ 1,092,502
                                                    ===========       ===========



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        2

   1359



                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)






                                                       Three months ended
                                                           March 31,
                                                 ------------------------------
                                                     2001            2000
                                                 ------------      ------------
                                                           
Revenues:
  Oil and gas                                    $    249,447      $    188,721
  Interest                                              1,529             1,467
                                                 ------------      ------------
                                                      250,976           190,188
                                                 ------------      ------------
Costs and expenses:
  Oil and gas production                              144,855            78,434
  General and administrative                            8,710             5,662
  Depletion                                            21,341            14,747
                                                 ------------      ------------
                                                      174,906            98,843
                                                 ------------      ------------
Net income                                       $     76,070      $     91,345
                                                 ============      ============
Allocation of net income:
  Managing general partner                       $        761      $        913
                                                 ============      ============
  Limited partners                               $     75,309      $     90,432
                                                 ============      ============
Net income per limited partnership interest      $     426.68      $     512.36
                                                 ============      ============





         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   1360



                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)







                                  Managing
                                  general            Limited
                                  partner            partners             Total
                                ------------       ------------       ------------
                                                             
Balance at January 1, 2001      $     12,767       $  1,064,292       $  1,077,059

    Distributions                       (943)           (93,317)           (94,260)

    Net income                           761             75,309             76,070
                                ------------       ------------       ------------

Balance at March 31, 2001       $     12,585       $  1,046,284       $  1,058,869
                                ============       ============       ============



         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4

   1361



                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)






                                                              Three months ended
                                                                  March 31,
                                                        -------------------------------
                                                            2001               2000
                                                        ------------       ------------
                                                                     
Cash flows from operating activities:
  Net income                                            $     76,070       $     91,345
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                              21,341             14,747
  Changes in assets and liabilities:
       Accounts receivable                                   (31,994)            (7,962)
       Accounts payable                                        2,405              1,850
                                                        ------------       ------------
         Net cash provided by operating activities            67,822             99,980
                                                        ------------       ------------
Cash flows from investing activities:
  Additions to oil and gas properties                        (14,685)               (94)
  Proceeds from disposition of assets                             --                158
                                                        ------------       ------------
         Net cash provided by (used in) investing
           activities                                        (14,685)                64
                                                        ------------       ------------
Cash flows used in financing activities:
  Cash distributions to partners                             (94,260)           (94,968)
                                                        ------------       ------------
Net increase (decrease) in cash                              (41,123)             5,076
Cash at beginning of period                                  101,600            105,420
                                                        ------------       ------------
Cash at end of period                                   $     60,477       $    110,496
                                                        ============       ============



         The financial information included herein has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        5



   1362



                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.     Organization and nature of operations

Parker & Parsley Private Investment 89, L.P. (the "Partnership") was organized
in 1989 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1990.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 32% to $249,447 for the three
months ended March 31, 2001 as compared to $188,721 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 5,909 barrels
of oil, 1,619 barrels of natural gas liquids ("NGLs") and 11,008 mcf of gas were
sold, or 9,363 barrel of oil equivalents ("BOEs"). For the three months ended

                                        6

   1363



March 31, 2000, 5,867 barrels of oil, 1,854 barrels of NGLs and 6,473 mcf of gas
were sold, or 8,800 BOEs.

The average price received per barrel of oil increased $.69, or 3%, from $26.78
for the three months ended March 31, 2000 to $27.47 for the same period in 2001.
The average price received per barrel of NGLs increased $5.15, or 44%, from
$11.59 for the three months ended March 31, 2000 to $16.74 for the same period
in 2001. The average price received per mcf of gas increased 249% from $1.56
during the three months ended March 31, 2000 to $5.45 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $174,906 for the three months ended March
31, 2001 as compared to $98,843 for the same period in 2000, an increase of
$76,063, or 77%. This increase was primarily due to increases in production
costs, general and administrative expenses ("G&A") and depletion.

Production costs were $144,855 for the three months ended March 31, 2001 and
$78,434 for the same period in 2000 resulting in a $66,421 increase, or 85%. The
increase was due to additional workover and well maintenance costs incurred to
stimulate well production and higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 54% from $5,662 for the three months ended March 31, 2000 to $8,710
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $21,341 for the three months ended March 31, 2001 as compared to
$14,747 for the same period in 2000, an increase of $6,594, or 45%. This
increase was primarily due to a downward revision to proved reserves on one
well.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities decreased $32,158 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
decrease was due to increases in production costs of $66,421, G&A expenses of
$3,048 and working capital of $23,477, offset by an increase in oil and gas
sales receipts of $60,788. The increase in oil and gas receipts resulted from

                                        7

   1364


the increase in commodity prices during 2001 which contributed an additional
$38,843 to oil and gas receipts and $21,945 resulting from the increase in
production during 2001 as compared to the same period in 2000. The increase in
production costs was primarily due to additional workover and well maintenance
costs incurred to stimulate well production and higher production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Provided by (Used in) Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Proceeds from disposition of assets of $158 recognized during the three months
ended March 31, 2000 were due to equipment credits received on one active well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $94,260, of which $943 was distributed to the managing general partner and
$93,317 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $94,968, of which $950 was distributed to the
managing general partner and $94,018 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8

   1365


   1366


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999




   1367



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Private Investment 89, L.P.
 (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley Private Investment 89,
L.P. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Private
Investment 89, L.P. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.



                                               Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   1368


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31



                                                            2000                1999
                                                         -----------        -----------
                                                                      

               ASSETS
               ------

Current assets:
  Cash                                                   $   101,600        $   105,420
  Accounts receivable - oil and gas sales                    118,399             76,918
                                                         -----------        -----------

         Total current assets                                219,999            182,338
                                                         -----------        -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                     5,223,723          5,213,140
Accumulated depletion                                     (4,351,220)        (4,291,008)
                                                         -----------        -----------

         Net oil and gas properties                          872,503            922,132
                                                         -----------        -----------

                                                         $ 1,092,502        $ 1,104,470
                                                         ===========        ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                           $    15,443        $    15,871

Partners' capital:
  Managing general partner                                    12,767             12,882
  Limited partners (176.5 interests)                       1,064,292          1,075,717
                                                         -----------        -----------

                                                           1,077,059          1,088,599
                                                         -----------        -----------

                                                         $ 1,092,502        $ 1,104,470
                                                         ===========        ===========





   The accompanying notes are an integral part of these financial statements.



                                       3
   1369


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                                 2000            1999            1998
                                                              ---------       ---------       ---------
                                                                                     

Revenues:
  Oil and gas                                                 $ 856,030       $ 487,809       $ 478,637
  Interest                                                        8,294           4,555           5,752
                                                              ---------       ---------       ---------

                                                                864,324         492,364         484,389
                                                              ---------       ---------       ---------

Costs and expenses:
  Oil and gas production                                        321,340         311,071         300,564
  General and administrative                                     28,583          19,470          16,898
  Impairment of oil and gas properties                                -          44,421          18,873
  Depletion                                                      60,212          76,798         258,483
                                                              ---------       ---------       ---------

                                                                410,135         451,760         594,818
                                                              ---------       ---------       ---------

Net income (loss)                                             $ 454,189       $  40,604       $(110,429)
                                                              =========       =========       =========

Allocation of net income (loss):
  Managing general partner                                    $   4,542       $     406       $  (1,104)
                                                              =========       =========       =========

  Limited partners                                            $ 449,647       $  40,198       $(109,325)
                                                              =========       =========       =========

Net income (loss) per limited partnership interest            $2,547.58       $  227.75       $ (619.41)
                                                              =========       =========       =========





   The accompanying notes are an integral part of these financial statements.



                                       4
   1370


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                    Managing
                                                     general           Limited
                                                     partner           partners             Total
                                                   -----------        -----------        -----------
                                                                                

Partners' capital at January 1, 1998               $    16,634        $ 1,447,067        $ 1,463,701

    Distributions                                       (2,019)          (199,798)          (201,817)

    Net loss                                            (1,104)          (109,325)          (110,429)
                                                   -----------        -----------        -----------

Partners' capital at December 31, 1998                  13,511          1,137,944          1,151,455

    Distributions                                       (1,035)          (102,425)          (103,460)

    Net income                                             406             40,198             40,604
                                                   -----------        -----------        -----------

Partners' capital at December 31, 1999                  12,882          1,075,717          1,088,599

    Distributions                                       (4,657)          (461,072)          (465,729)

    Net income                                           4,542            449,647            454,189
                                                   -----------        -----------        -----------

Partners' capital at December 31, 2000             $    12,767        $ 1,064,292        $ 1,077,059
                                                   ===========        ===========        ===========





   The accompanying notes are an integral part of these financial statements.



                                       5
   1371


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                                2000             1999             1998
                                                              ---------        ---------        ---------
                                                                                        

Cash flows from operating activities:
   Net income (loss)                                          $ 454,189        $  40,604         (110,429)
   Adjustments to reconcile net income (loss) to
      net cash provided by operating activities:
          Impairment of oil and gas properties                        -           44,421           18,873
          Depletion                                              60,212           76,798          258,483
   Changes in assets and liabilities:
          Accounts receivable                                   (41,481)         (30,189)          17,499
          Accounts payable                                         (428)           3,058           (9,920)
                                                              ---------        ---------        ---------

            Net cash provided by operating activities           472,492          134,692          174,506
                                                              ---------        ---------        ---------

Cash flows from investing activities:
   Additions to oil and gas properties                          (10,741)         (10,151)         (14,992)
   Proceeds from asset dispositions                                 158                -            6,106
                                                              ---------        ---------        ---------

            Net cash used in investing activities               (10,583)         (10,151)          (8,886)
                                                              ---------        ---------        ---------

Cash flows used in financing activities:
   Cash distributions to partners                              (465,729)        (103,460)        (201,817)
                                                              ---------        ---------        ---------

Net increase (decrease) in cash                                  (3,820)          21,081          (36,197)
Cash at beginning of year                                       105,420           84,339          120,536
                                                              ---------        ---------        ---------

Cash at end of year                                           $ 101,600        $ 105,420        $  84,339
                                                              =========        =========        =========





   The accompanying notes are an integral part of these financial statements.



                                       6
   1372


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley Private Investment 89, L.P. (the "Partnership") was
organized in 1989 as a general partnership under the laws of the State of Texas
and was converted to a Delaware limited partnership in 1990. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.


                                       7
   1373


        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non- partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $44,421 and $18,873
related to its proved oil and gas properties during 1999 and 1998, respectively.



                                       8
   1374


NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $49,559 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                  2000             1999             1998
                                                                ---------        ---------        ---------
                                                                                         

Net income (loss) per statements of operations                  $ 454,189        $  40,604        $(110,429)
Impairment of oil and gas properties for financial
  reporting purposes                                                    -           44,421           18,873
Depletion and depreciation for tax reporting purposes
  less than amounts for financial reporting purposes               49,670           66,310          239,923
Other, net                                                         (1,023)          (3,073)           9,369
                                                                ---------        ---------        ---------

     Net income per Federal income tax returns                  $ 502,836        $ 148,262        $ 157,736
                                                                =========        =========        =========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                           2000            1999             1998
                                        ----------      ----------       ----------
                                                                

Development costs                       $   10,741      $   10,151       $   14,992
                                        ==========      ==========       ==========


        Capitalized oil and gas properties consist of the following:



                                              2000                1999
                                           -----------        -----------
                                                        

Proved properties:
  Property acquisition costs               $    58,953        $    58,953
  Completed wells and equipment              5,164,770          5,154,187
                                           -----------        -----------

                                             5,223,723          5,213,140
Accumulated depletion                       (4,351,220)        (4,291,008)
                                           -----------        -----------

     Net oil and gas properties            $   872,503        $   922,132
                                           ===========        ===========




                                       9
   1375

NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                         2000            1999            1998
                                                      ---------       ---------       ---------
                                                                             

Payment of lease operating and supervision
  charges in accordance with standard
  industry operating agreements                       $ 126,729       $ 122,574       $ 123,196

Reimbursement of general and administrative
  expenses                                            $  25,581       $  14,534       $  14,259


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 89 Private Conv., L.P. ("EMPL") and the Partnership are parties to
the Program agreement. EMPL is a limited partnership organized for the benefit
of certain employees of Pioneer USA. EMPL was merged with Pioneer USA on
December 28, 2000.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                      Pioneer USA (1)       Partnership
                                                                      ---------------       -----------
                                                                                      
Revenues:
  Proceeds from disposition of depreciable and
     depletable properties -
       First three years                                                14.141414%           85.858586%
       After three years                                                19.191919%           80.808081%
  All other revenues -
       First three years                                                14.141414%           85.858586%
       After three years                                                19.191919%           80.808081%
Costs and expenses:
  Lease acquisition costs, drilling and completion costs                 9.090909%           90.909091%
  Operating costs, reporting and legal expenses and
     general and administrative expenses -
        First three years                                               14.141414%           85.858586%
        After three years                                               19.191919%           80.808081%


(1)   Excludes Pioneer USA's 1% general partner ownership which is allocated at
      the Partnership level.

NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                                  Oil and NGLs         Gas
                                                     (bbls)           (mcf)
                                                  ------------      --------
                                                             

Net proved reserves at January 1, 1998               480,284         559,912
Revisions                                           (179,534)       (180,570)
Production                                           (36,741)        (44,624)
                                                    --------        --------

Net proved reserves at December 31, 1998             264,009         334,718
Revisions                                            227,645         277,954
Production                                           (30,310)        (32,985)
                                                    --------        --------

Net proved reserves at December 31, 1999             461,344         579,687
Revisions                                             37,767         (55,380)
Production                                           (30,738)        (30,037)
                                                    --------        --------

Net proved reserves at December 31, 2000             468,373         494,270
                                                    ========        ========




                                       10
   1376


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.18 per barrel of NGLs and $7.93 per mcf of gas,
discounted at 10% was approximately $3,336,000 and undiscounted was $6,999,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                        For the years ended December 31,
                                                                  -------------------------------------------
                                                                     2000             1999             1998
                                                                  ---------        ---------        ---------
                                                                                (in thousands)
                                                                                           

Oil and gas producing activities:
   Future cash inflows                                            $  14,511        $  11,459        $   2,862
   Future production costs                                           (7,512)          (6,395)          (2,112)
                                                                  ---------        ---------        ---------

                                                                      6,999            5,064              750
   10% annual discount factor                                        (3,663)          (2,516)            (271)
                                                                  ---------        ---------        ---------

   Standardized measure of discounted future net cash flows       $   3,336        $   2,548        $     479
                                                                  =========        =========        =========




                                       11
   1377



                                                                 For the years ended December 31,
                                                            ----------------------------------------
                                                              2000            1999            1998
                                                            --------        --------        --------
                                                                         (in thousands)
                                                                                   

Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs                $   (535)       $   (177)       $   (178)
  Net changes in prices and production costs                   1,060           1,324          (1,107)
  Revisions of previous quantity estimates                       183           1,588            (261)
  Accretion of discount                                          255              48             189
  Changes in production rates, timing and other                 (175)           (714)            (48)
                                                            --------        --------        --------

  Change in present value of future net revenues                 788           2,069          (1,405)
                                                            --------        --------        --------

  Balance, beginning of year                                   2,548             479           1,884
                                                            --------        --------        --------

  Balance, end of year                                      $  3,336        $  2,548        $    479
                                                            ========        ========        ========


NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                                   2000            1999             1998
                                                 --------        --------         --------
                                                                         

Plains Marketing, L.P.                              65%             64%               -
Genesis Crude Oil, L.P.                              -               -               57%
Western Gas Resources, Inc.                          1%              3%              15%
GPM Gas Corporation                                  3%              3%               5%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $48,161 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the limited partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. In return, it is allocated 1% of the Partnership's revenues.


                                       12
   1378


        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $7,060,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent its share of revenues does not cover such costs.



                                       13
   1379


                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 75% to $856,030 for 2000 as
compared to $487,809 in 1999. The increase in revenues resulted from higher
average prices received, offset by a slight decline in production. In 2000,
22,438 barrels of oil, 8,300 barrels of natural gas liquids ("NGLs") and 30,037
mcf of gas were sold, or 35,744 barrel of oil equivalents ("BOEs"). In 1999,
20,601 barrels of oil, 9,709 barrels of NGLs and 32,985 mcf of gas were sold, or
35,808 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $11.94, or 70%, from
$17.06 in 1999 to $29.00 in 2000. The average price received per barrel of NGLs
increased $6.17, or 71%, from $8.69 in 1999 to $14.86 in 2000. The average price
received per mcf of gas increased 74% from $1.57 in 1999 to $2.73 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses decreased in 2000 to $410,135 as compared to $451,760
in 1999, a decrease of $41,625, or 9%. The decrease was due to a decline in
depletion and the impairment of oil and gas properties, offset by an increase in
production costs and general and administrative expenses ("G&A").

Production costs were $321,340 in 2000 and $311,071 in 1999, resulting in a
$10,269 increase, or 3%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices, offset by lower well
maintenance costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
47% from $19,470 in 1999 to $28,583 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $25,581 in 2000 and $14,534 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long- Lived Assets and for Long-Lived Assets
to be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $44,421 related to its oil and gas properties during 1999.

Depletion was $60,212 in 2000 as compared to $76,798 in 1999, representing a
decrease of $16,586, or 22%. This decrease was primarily due to a 23,945 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices and a reduction in the Partnership's net depletable basis from charges
taken in accordance with SFAS 121 during the fourth quarter of 1999.


   1380


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 2% to $487,809 from
$478,637 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 20,601 barrels of oil,
9,709 barrels of NGLs and 32,985 mcf of gas were sold, or 35,808 BOEs. In 1998,
25,672 barrels of oil, 11,069 barrels of NGLs and 44,624 mcf of gas were sold,
or 44,178 BOEs.

The average price received per barrel of oil increased $3.78, or 28%, from
$13.28 in 1998 to $17.06 in 1999. The average price received per barrel of NGLs
increased $2.12, or 32%, from $6.57 in 1998 to $8.69 in 1999. The average price
received per mcf of gas increased 8% from $1.46 in 1998 to $1.57 in 1999.

Total costs and expenses decreased in 1999 to $451,760 as compared to $594,818
in 1998, a decrease of $143,058, or 24%. The decrease was due to a decline in
depletion, offset by an increase in the impairment of oil and gas properties,
production costs and G&A.

Production costs were $311,071 in 1999 and $300,564 in 1998, resulting in a
$10,507 increase, or 3%. The increase was due to an increase in well maintenance
costs incurred to stimulate well production, offset by declines in ad valorem
and production taxes.

During this period, G&A increased 15% from $16,898 in 1998 to $19,470 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $14,534 in
1999 and $14,259 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $44,421 and $18,873
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion was $76,798 in 1999 compared to $258,483 in 1998, representing a
decrease of $181,685, or 70%. This decrease was the result of a combination of
factors that included an increase in proved reserves of 160,524 barrels of oil
during 1999 as a result of higher commodity prices, a decline in oil production
of 5,071 barrels for the period ended December 31, 1999 compared to the same
period in 1998 and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $337,800 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $371,960, offset by increases in production costs paid
of


   1381


$10,269, G&A expenses paid of $9,113 and working capital of $14,778. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $347,665 to oil and gas receipts and
an increase of $24,295 resulting from the increase in oil production during
2000. The increase in production costs was primarily due to increased production
taxes associated with higher oil and gas prices, offset by lower well
maintenance costs. The increase in G&A was primarily due to higher percentage of
the managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active properties.

Proceeds from asset dispositions of $158 in 2000 were from equipment credits
received on one active well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $465,729, of which $4,657 was
distributed to the managing general partner and $461,072 to the limited
partners. In 1999, cash distributions to the partners were $103,460, of which
$1,035 was distributed to the managing general partner and $102,425 to the
limited partners.




   1382




                  PARKER & PARSLEY PRIVATE INVESTMENT 89, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  188,721   $  856,030   $  487,809   $  478,637   $  675,051   $  800,390
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $   44,421   $   18,873   $  377,878   $   79,530
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   91,345   $  454,189   $   40,604   $ (110,429)  $ (183,640)  $  249,498
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      913   $    4,542   $      406   $   (1,104)  $   (1,836)  $    2,495
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   90,432   $  449,647   $   40,198   $ (109,325)  $ (181,804)  $  247,003
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   512.36   $ 2,547.58   $   227.75   $  (619.41)  $(1,030.05)  $ 1,399.45
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   532.68   $ 2,612.31   $   580.31   $ 1,132.00   $ 2,068.82   $ 1,932.01
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $1,102,697   $1,092,502   $1,104,470   $1,164,268   $1,486,434   $2,033,774
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1383
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 90-A CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
90-A Conv., L.P., and supplements the proxy statement/prospectus dated         ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 90-A Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-
   1384

                        PARKER & PARSLEY 90-A CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $   2,359

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $   2,146

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $     565
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  240.83

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.18 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  183.28

        --        as of December 31, 2000  (c)                                                 $  183.97

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  223.33

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  233.82

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     125
(c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2040, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.



                                      -2-
   1385

                       PARKER & PARSLEY 90-A CONV., L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   1386


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS



                                                       March 31,     December 31,
                                                         2001            2000
                                                     ------------    ------------
                                                     (Unaudited)
                                                               

                 ASSETS
Current assets:
  Cash                                               $     33,356    $     30,771
  Accounts receivable - oil and gas sales                  43,865          42,233
                                                     ------------    ------------
        Total current assets                               77,221          73,004
                                                     ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                  1,762,459       1,761,261
Accumulated depletion                                  (1,397,191)     (1,390,348)
                                                     ------------    ------------
        Net oil and gas properties                        365,268         370,913
                                                     ------------    ------------
                                                     $    442,489    $    443,917
                                                     ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $      5,733    $      5,524

Partners' capital:
  Managing general partner                                  4,396           4,412
  Limited partners (2,359 interests)                      432,360         433,981
                                                     ------------    ------------
                                                          436,756         438,393
                                                     ------------    ------------
                                                     $    442,489    $    443,917
                                                     ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        2

   1387


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                    Three months ended
                                                         March 31,
                                                 -----------------------
                                                    2001         2000
                                                 ----------   ----------
                                                        
Revenues:
  Oil and gas                                    $   81,855   $   63,489
  Interest                                              563          534
                                                 ----------   ----------
                                                     82,418       64,023
                                                 ----------   ----------
Costs and expenses:
  Oil and gas production                             26,631       24,535
  General and administrative                          2,954        1,913
  Depletion                                           6,843        7,138
                                                 ----------   ----------
                                                     36,428       33,586
                                                 ----------   ----------
Net income                                       $   45,990   $   30,437
                                                 ==========   ==========
Allocation of net income:
  Managing general partner                       $      460   $      304
                                                 ==========   ==========
  Limited partners                               $   45,530   $   30,133
                                                 ==========   ==========
Net income per limited partnership interest      $    19.30   $    12.77
                                                 ==========   ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   1388



                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                      Managing
                                       general       Limited
                                       partner       partners        Total
                                     ----------     ----------    ----------
                                                         
Balance at January 1, 2001            $    4,412    $  433,981    $  438,393

    Distributions                           (476)      (47,151)      (47,627)

    Net income                               460        45,530        45,990
                                      ----------    ----------    ----------

Balance at March 31, 2001             $    4,396    $  432,360    $  436,756
                                      ==========    ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4

   1389


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                          Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001           2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $   45,990    $   30,437
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            6,843         7,138
  Changes in assets and liabilities:
       Accounts receivable                                 (1,632)       (3,963)
       Accounts payable                                       209            15
                                                       ----------    ----------
         Net cash provided by operating activities         51,410        33,627
                                                       ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                      (1,198)         (482)

Cash flows used in financing activities:
  Cash distributions to partners                          (47,627)      (30,267)
                                                       ----------    ----------
Net increase in cash                                        2,585         2,878
Cash at beginning of period                                30,771        41,094
                                                       ----------    ----------
Cash at end of period                                  $   33,356    $   43,972
                                                       ==========    ==========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   1390



                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 90-A Conv., L.P. (the "Partnership") was organized in 1990 as a
general partnership under the laws of the State of Texas and was converted to a
Delaware limited partnership in 1991.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
    Results of Operations (1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 29% to $81,855 for the three
months ended March 31, 2001 as compared to $63,489 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 1,635
barrels of oil, 533 barrels of natural gas liquids ("NGLs") and 4,098 mcf of gas
were sold, or 2,851 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 1,650 barrels of oil, 877 barrels of NGLs and 3,430 mcf of
gas were sold, or 3,099 BOEs.



                                        6
   1391




The average price received per barrel of oil increased $1.00, or 4%, from $27.38
for the three months ended March 31, 2000 to $28.38 for the same period in 2001.
The average price received per barrel of NGLs increased $5.61, or 41%, from
$13.78 for the three months ended March 31, 2000 to $19.39 for the same period
in 2001. The average price received per mcf of gas increased 236% from $1.82
during the three months ended March 31, 2000 to $6.12 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $36,428 for the three months ended March
31, 2001 as compared to $33,586 for the same period in 2000, an increase of
$2,842, or 8%. This increase was primarily due to increases in production costs
and general and administrative expenses ("G&A"), offset by a decline in
depletion.

Production costs were $26,631 for the three months ended March 31, 2001 and
$24,535 for the same period in 2000 resulting in a $2,096 increase, or 9%. The
increase was due to higher production taxes associated with higher oil and gas
prices and additional well maintenance costs incurred to stimulate well
production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 54% from $1,913 for the three months ended March 31, 2000 to $2,954
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $6,843 for the three months ended March 31, 2001 as compared to
$7,138 for the same period in 2000, a decrease of $295, or 4%. This decrease was
primarily due to positive revisions to proved reserves during the three months
ended March 31, 2001 as a result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $17,783 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $18,395 and a
reduction in working capital of $2,525, offset by increases in production costs
of $2,096 and G&A expenses of $1,041. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an



                                        7

   1392


additional $21,406 to oil and gas receipts, offset by $3,011 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues and an
increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $47,627, of which $476 was distributed to the managing general partner and
$47,151 to the limited partners. For the same period ended March 31, 2000, cash
distributions to the partners were $30,267 of which $303 was distributed to the
managing general partner and $29,964 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)   "Management's Discussion and Analysis of Financial Condition and Results
      of Operations" contains forward looking statements that involve risks and
      uncertainties. Accordingly, no assurances can be given that the actual
      events and results will not be materially different than the anticipated
      results described in the forward looking statements.




                                        8


   1393
                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999



   1394

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90-A Conv., L.P.
 (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90-A Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90-A Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001

                                       2
   1395


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                     2000          1999
                                                                   --------      ---------
                                                                         
              ASSETS
              ------

Current assets:
  Cash                                                           $   30,771     $   41,094
  Accounts receivable - oil and gas sales                            42,233         24,997
                                                                   --------       --------

       Total current assets                                          73,004         66,091
                                                                   --------       --------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                            1,761,261      1,758,206
Accumulated depletion                                            (1,390,348)    (1,363,812)
                                                                 ----------     -----------

       Net oil and gas properties                                   370,913        394,394
                                                                   --------       --------

                                                                 $  443,917     $  460,485
                                                                  =========      =========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                   $    5,524     $    5,332

Partners' capital:
  Managing general partner                                            4,412          4,579
  Limited partners (2,359 interests)                                433,981        450,574
                                                                   --------       ---------

                                                                    438,393        455,153
                                                                   --------       --------
                                                                 $  443,917     $  460,485
                                                                  =========      =========


   The accompanying notes are an integral part of these financial statements.

                                       3
   1396


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                         2000          1999          1998
                                                       -------       -------        ------

                                                                       
Revenues:
  Oil and gas                                        $ 279,230     $ 169,279      $152,905
  Interest                                               3,027         1,751         2,080
  Gain on disposition of assets                          3,262           -             -
                                                       -------       -------        ------

                                                       285,519       171,030       154,985
                                                       -------       -------       -------

Costs and expenses:
  Oil and gas production                               114,159        93,178        97,819
  General and administrative                             9,468         7,068         4,961
  Impairment of oil and gas properties                     -             -          11,795
  Depletion                                             26,536        36,271        55,908
                                                       -------       -------        ------

                                                       150,163       136,517       170,483
                                                       -------       -------       -------

Net income (loss)                                    $ 135,356     $  34,513      $(15,498)
                                                      ========      ========       =======

Allocation of net income (loss):
  Managing general partner                           $   1,354     $     345      $   (155)
                                                      ========      ========       =======

  Limited partners                                   $ 134,002     $  34,168      $(15,343)
                                                      ========      ========       =======

Net income (loss) per limited partnership interest   $   56.80     $   14.48      $  (6.50)
                                                      ========      ========       =======


   The accompanying notes are an integral part of these financial statements.

                                       3
   1397


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                     Managing
                                                     general       Limited
                                                     partner       partners         Total
                                                   ------------- -------------- -----------


                                                                       
Partners' capital at January 1, 1998               $  5,602      $  551,772     $ 557,374

   Distributions                                       (678)        (67,095)      (67,773)

   Net loss                                            (155)        (15,343)      (15,498)
                                                     ------        --------       -------

Partners' capital at December 31, 1998                4,769         469,334       474,103

   Distributions                                       (535)        (52,928)      (53,463)

   Net income                                           345          34,168        34,513
                                                     ------        --------       -------

Partners' capital at December 31, 1999                4,579         450,574       455,153

   Distributions                                     (1,521)       (150,595)     (152,116)

   Net income                                         1,354         134,002       135,356
                                                     ------        --------       -------

Partners' capital at December 31, 2000             $  4,412      $  433,981     $ 438,393
                                                    =======       =========      ========


   The accompanying notes are an integral part of these financial statements.

                                       5
   1398


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                       2000         1999           1998
                                                     -------       -------        -------

                                                                       

Cash flows from operating activities:
   Net income (loss)                               $ 135,356     $  34,513      $ (15,498)
   Adjustments to reconcile net income (loss) to
     net cash provided by operating activities:
       Impairment of oil and gas properties              -             -           11,795
       Depletion                                      26,536        36,271         55,908
       Gain on disposition of assets                  (3,262)          -              -
   Changes in assets and liabilities:
       Accounts receivable                           (17,236)       (7,632)        12,991
       Accounts payable                                  192           841         (2,835)
                                                     -------       -------        -------

         Net cash provided by operating activities   141,586        63,993         62,361
                                                    --------       -------        -------

Cash flows from investing activities:
   Additions to oil and gas properties                (3,055)       (2,507)        (3,134)
   Proceeds from asset dispositions                    3,262         2,501            -
                                                     -------       -------        -------

         Net cash provided by (used in)
            investing activities                         207            (6)        (3,134)
                                                     -------       -------        -------

Cash flows used in financing activities:
   Cash distributions to partners                   (152,116)      (53,463)       (67,773)
                                                    --------       -------        -------

Net increase (decrease) in cash                      (10,323)       10,524         (8,546)
Cash at beginning of year                             41,094        30,570         39,116
                                                     -------       -------        -------

Cash at end of year                                $  30,771     $  41,094      $  30,570
                                                    ========      ========       ========


   The accompanying notes are an integral part of these financial statements.

                                       6
   1399


                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 90-A Conv., L.P. (the "Partnership") was organized in
1990 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1991. The Partnership's managing
general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

                                       7
   1400

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.       IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $11,795 related to its
proved oil and gas properties during 1998.

                                       8
   1401

NOTE 4.       INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $109,150 greater than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                           2000         1999        1998
                                                        ---------    ---------   ---------

                                                                         
Net income (loss) per statements of operations           $135,356      $34,513    $(15,498)
Depletion and depreciation for tax reporting purposes
  less than amounts for financial reporting purposes       23,651       33,412      51,723
Impairment of oil and gas properties for financial
  reporting purposes                                           --           --      11,795
Other, net                                                   (403)       1,343       1,229
                                                        ---------    ---------   ---------

Net income per Federal income tax returns                $158,604      $69,268     $49,249
                                                        =========    =========   =========


NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                   ---------     ---------      ---------

                                                                       
    Development costs                              $   3,055     $   2,507      $   3,134
                                                   =========     =========      =========


      Capitalized oil and gas properties consist of the following:



                                                                      2000           1999
                                                                    ---------      ---------

                                                                            
    Proved properties:
      Property acquisition costs                                 $     69,332     $   69,332
      Completed well and equipment                                  1,691,929      1,688,874
                                                                    ---------      ---------

                                                                    1,761,261      1,758,206
    Accumulated depletion                                          (1,390,348)    (1,363,812)
                                                                   ----------     ----------

          Net oil and gas properties                             $    370,913     $  394,394
                                                                    =========      =========




                                       9
   1402


NOTE 6.       RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999           1998
                                                   ---------     ---------      ---------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard industry
      operating agreements                         $  42,503     $  41,777      $  41,366

    Reimbursement of general and administrative
      expenses                                     $   8,329     $   5,027      $   4,007


      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 90-A Conv., L.P. ("EMPL"), Parker & Parsley 90-A, L.P. and the
Partnership are parties to the Program agreement. EMPL is a limited partnership
organized for the benefit of certain employees of Pioneer USA. EMPL was merged
with Pioneer USA on December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                             Pioneer USA (1)   Partnerships (2)
                                                             ---------------   ----------------
                                                                          
Revenues:
  Proceeds from disposition of depreciable and
    depletable properties -
      First three years                                         14.141414%       85.858586%
      After first three years                                   19.191919%       80.808081%
  All other revenues -
      First three years                                         14.141414%       85.858586%
      After first three years                                   19.191919%       80.808081%

Costs and expenses:
  Lease acquisition costs, drilling and completion costs         9.090909%       90.909091%
  Operating costs, reporting and legal expenses and
    general and administrative expenses -
      First three years                                         14.141414%       85.858586%
      After first three years                                   19.191919%       80.808081%


      (1)   Excludes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 14 limited partner interests
            owned by Pioneer USA.

      (2)   The allocation between the Partnership and Parker & Parsley 90-A,
            L.P. is 25.725191% and 74.274809%, respectively.

NOTE 7.       OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       10
   1403



                                                              Oil and NGLs         Gas
                                                                 (bbls)           (mcf)
                                                              ------------      ----------

                                                                          
      Net proved reserves at January 1, 1998                      137,987          205,757
      Revisions                                                   (49,089)         (52,907)
      Production                                                  (11,399)         (16,309)
                                                               ----------       ----------

      Net proved reserves at December 31, 1998                     77,499          136,541
      Revisions                                                    71,585          121,688
      Production                                                  (10,130)         (14,989)
                                                               ----------       ----------

      Net proved reserves at December 31, 1999                    138,954          243,240
      Revisions                                                     6,057          (59,715)
      Production                                                   (9,876)         (13,365)
                                                               ----------       ----------

      Net proved reserves at December 31, 2000                    135,135          170,160
                                                               ==========       ==========


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.25 per barrel of NGLs and $7.89 per mcf of gas,
discounted at 10% was approximately $1,053,000 and undiscounted was $2,025,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                For the years ended December 31,
                                                             --------------------------------------
                                                                 2000          1999         1998
                                                             -----------   -----------  -----------
                                                                         (in thousands)
                                                                               
Oil and gas producing activities:
  Future cash inflows                                        $    4,309    $    3,455   $      854
  Future production costs                                        (2,284)       (2,046)        (669)
                                                               --------      --------     --------

                                                                  2,025         1,409          185
  10% annual discount factor                                       (972)         (653)         (54)
                                                               --------      --------     --------

  Standardized measure of discounted future net cash flows   $    1,053    $      756   $      131
                                                              =========     =========    =========


                                       11
   1404



                                                          For the years ended December 31,
                                                       --------------------------------------
                                                           2000          1999         1998
                                                       -----------   -----------  -----------
                                                                    (in thousands)
                                                                        
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (165)  $       (76)  $      (55)
    Net changes in prices and production costs                446           419         (356)
    Revisions of previous quantity estimates                  (26)          511          (61)
    Accretion of discount                                      76            13           56
    Changes in production rates, timing and other             (34)         (242)         (14)
                                                         --------     ---------     --------

    Change in present value of future net revenues            297           625         (430)
                                                         --------     ---------     --------

    Balance, beginning of year                                756           131          561
                                                         --------     ---------     --------

    Balance, end of year                               $    1,053   $       756   $      131
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

  The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:



                                                         2000         1999          1998
                                                       --------     --------      --------

                                                                         
              Plains Marketing, L.P.                      54%           51%            -
              TEPPCO Crude Oil LLC                        12%           11%            -
              NGTS LLC                                    10%           10%            -
              Genesis Crude Oil, L.P.                      -             -            57%
              Western Gas Resources, Inc.                  2%            5%           22%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
TEPPCO Crude Oil LLC and NGTS LLC were $13,068, $2,535 and $1,423, respectively,
which are included in the caption "Accounts receivable - oil and gas sales" in
the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.       PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the Partnership agreement, the managing general partner pays 1% of
      the Partnership's acquisition, drilling and completion costs and 1% of its
      operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

                                       12
   1405

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The partners entered into subscription
      agreements for aggregate capital contributions of $2,359,000. Pioneer USA
      is required to contribute amounts equal to 1% of initial Partnership
      capital less commission, organization and offering costs allocated to the
      limited partners and to contribute amounts necessary to pay costs and
      expenses allocated to it under the Partnership agreement to the extent its
      share of revenues does not cover such costs.

                                       13
   1406
                        PARKER & PARSLEY 90-A CONV., L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
  RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 65% to $279,230 for 2000 as
compared to $169,279 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 6,255
barrels of oil, 3,621 barrels of natural gas liquids ("NGLs") and 13,365 mcf of
gas were sold, or 12,104 barrel of oil equivalents ("BOEs"). In 1999, 6,133
barrels of oil, 3,997 barrels of NGLs and 14,989 mcf of gas were sold, or 12,628
BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.26, or 72%, from
$17.06 in 1999 to $29.32 in 2000. The average price received per barrel of NGLs
increased $6.04, or 63%, from $9.58 in 1999 to $15.62 in 2000. The average price
received per mcf of gas increased 67% from $1.76 in 1999 to $2.94 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $3,262 was recognized during 2000 resulting
from equipment credits received on one well.

Total costs and expenses increased in 2000 to $150,163 as compared to $136,517
in 1999, an increase of $13,646, or 10%. The increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $114,159 in 2000 and $93,178 in 1999, resulting in a
$20,981 increase, or 23%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
34% from $7,068 in 1999 to $9,468 in 2000, primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $8,329 in 2000 and $5,027 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $26,536 in 2000 as compared to $36,271 in 1999, representing a
decrease of $9,735, or 27%. This decrease was primarily due to a 10,806 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 11% to $169,279 from
$152,905 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 6,133 barrels of oil,
3,997 barrels

   1407
of NGLs and 14,989 mcf of gas were sold, or 12,628 BOEs. In 1998, 7,476 barrels
of oil, 3,923 barrels of NGLs and 16,309 mcf of gas were sold, or 14,117 BOEs.

The average price received per barrel of oil increased $3.86, or 29%, from
$13.20 in 1998 to $17.06 in 1999. The average price received per barrel of NGLs
increased $2.56, or 36%, from $7.02 in 1998 to $9.58 in 1999. The average price
received per mcf of gas increased 7% from $1.64 in 1998 to $1.76 in 1999.

Total costs and expenses decreased in 1999 to $136,517 as compared to $170,483
in 1998, a decrease of $33,966, or 20%. The decrease was due to reductions in
depletion, the impairment of oil and gas properties and production costs, offset
by an increase in G&A.

Production costs were $93,178 in 1999 and $97,819 in 1998, resulting in a $4,641
decrease, or 5%. The decrease was due to declines in ad valorem taxes and well
maintenance costs.

During this period, G&A increased 42% from $4,961 in 1998 to $7,068 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $5,027 in
1999 and $4,007 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $11,795 related to its oil and gas properties during 1998.

Depletion was $36,271 in 1999 compared to $55,908 in 1998, representing a
decrease of $19,637, or 35%. This decrease was primarily the result of an
increase in proved reserves of 43,411 barrels of oil during 1999 as a result of
higher commodity prices, a reduction in the Partnership's net depletable basis
from charges taken in accordance with SFAS 121 during the fourth quarter of 1998
and a decline in oil production of 1,343 barrels for the period ended December
31, 1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.




Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $77,593 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $111,227, offset by increases in production costs paid
of


   1408

$20,981, G&A expenses paid of $2,400 and working capital of $10,253. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $118,292 to oil and gas receipts,
offset by $7,065 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active properties.

Proceeds from disposition of assets of $3,262 was recognized during 2000
resulting from equipment credits received on one well. Proceeds of $2,501 during
1999 were received from equipment credits on one active well and one temporarily
abandoned well.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $152,116, of which $1,521 was
distributed to the managing general partner and $150,595 to the limited
partners. In 1999, cash distributions to the partners were $53,463, of which
$535 was distributed to the managing general partner and $52,928 to the limited
partners.

   1409




                        PARKER & PARSLEY 90-A CONV., L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $   63,489   $  279,230   $  169,279   $  152,905   $  223,014   $  269,347
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   11,795   $  111,163   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   30,437   $  135,356   $   34,513   $  (15,498)  $  (51,948)  $   90,354
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      304   $    1,354   $      345   $     (155)  $     (520)  $      903
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   30,133   $  134,002   $   34,168   $  (15,343)  $  (51,428)  $   89,451
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    12.77   $    56.80   $    14.48   $    (6.50)  $   (21.80)  $    37.92
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    12.70   $    63.84   $    22.44   $    28.44   $    53.06   $    53.75
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  460,670   $  443,917   $  460,485   $  478,594   $  564,700   $  742,427
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1410
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 90-A, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
90-A, L.P., and supplements the proxy statement/prospectus dated      , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 90-A, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1411

                           PARKER & PARSLEY 90-A, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $   6,811

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $   6,196

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   1,609
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  241.44

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.14 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  183.88

        --        as of December 31, 2000  (c)                                                 $  184.56

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  223.94

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  234.43

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     125
(c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or before July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.



                                      -2-
   1412


                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-26097-05


                           PARKER & PARSLEY 90-A, L.P.
             (Exact name of Registrant as specified in its charter)

                        Delaware                           75-2329245
            ----------------------------------        ---------------------
             (State or other jurisdiction of            (I.R.S. Employer
             incorporation or organization)           Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.


                                Yes [x]   No [ ]

   1413



                           PARKER & PARSLEY 90-A, L.P.

                                TABLE OF CONTENTS



                                                                      Page
                                                                
                          Part I. Financial Information

Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000......................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000...........................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000...........................    6

           Notes to Financial Statements.............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K..........................    9

           Signatures................................................   10



                                        2

   1414



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS


                                                     March 31,      December 31,
                                                       2001             2000
                                                    -----------     -----------
                                                    (Unaudited)
                 ASSETS

                                                              
Current assets:
  Cash                                              $   100,813     $    92,685
  Accounts receivable - oil and gas sales               126,818         122,067
                                                    -----------     -----------
         Total current assets                           227,631         214,752
                                                    -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                5,088,642       5,085,185
Accumulated depletion                                (4,034,102)     (4,014,368)
                                                    -----------     -----------
         Net oil and gas properties                   1,054,540       1,070,817
                                                    -----------     -----------
                                                    $ 1,282,171     $ 1,285,569
                                                    ===========     ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $    17,041     $    15,770

Partners' capital:
  Managing general partner                               12,732          12,779
  Limited partners (6,811 interests)                  1,252,398       1,257,020
                                                    -----------     -----------
                                                      1,265,130       1,269,799
                                                    -----------     -----------
                                                    $ 1,282,171     $ 1,285,569
                                                    ===========     ===========



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   1415



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                      Three months ended
                                                            March 31,
                                                   --------------------------
                                                      2001            2000
                                                   ----------      ----------
                                                             
Revenues:
  Oil and gas                                      $  236,358      $  183,303
  Interest                                              1,657           1,583
                                                   ----------      ----------
                                                      238,015         184,886
                                                   ----------      ----------
Costs and expenses:
  Oil and gas production                               76,877          70,816
  General and administrative                            8,561           5,681
  Depletion                                            19,734          20,632
                                                   ----------       ---------
                                                      105,172          97,129
                                                   ----------      ----------
Net income                                         $  132,843      $   87,757
                                                   ==========      ==========
Allocation of net income:
  Managing general partner                         $    1,328      $      878
                                                   ==========      ==========
  Limited partners                                 $  131,515      $   86,879
                                                   ==========      ==========
Net income per limited partnership interest        $    19.31      $    12.76
                                                   ==========      ==========



       The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        4

   1416



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                        Managing
                                        general        Limited
                                        partner        partners        Total
                                       ----------     ----------     ----------
                                                            
Balance at January 1, 2001             $   12,779     $1,257,020     $1,269,799

    Distributions                          (1,375)      (136,137)      (137,512)

    Net income                              1,328        131,515        132,843
                                       ----------     ----------     ----------

Balance at March 31, 2001              $   12,732     $1,252,398     $1,265,130
                                       ==========     ==========     ==========



       The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   1417


                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                        Three months ended
                                                             March 31,
                                                     -------------------------
                                                        2001           2000
                                                     ----------     ----------
                                                              
Cash flows from operating activities:
  Net income                                         $  132,843     $   87,757
  Adjustments to reconcile net income to net
    cash provided by operating activities:
      Depletion                                          19,734         20,632
  Changes in assets and liabilities:
      Accounts receivable                                (4,751)       (11,460)
      Accounts payable                                    1,271            346
                                                     ----------     ----------
        Net cash provided by operating activities       149,097         97,275
                                                     ----------     ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                    (3,457)        (1,393)
Cash flows used in financing activities:
  Cash distributions to partners                       (137,512)       (87,388)
                                                     ----------     ----------
Net increase in cash                                      8,128          8,494
Cash at beginning of period                              92,685        122,649
                                                     ----------     ----------
Cash at end of period                                $  100,813     $  131,143
                                                     ==========     ==========





         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        6
   1418


                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1. Organization and nature of operations

Parker & Parsley 90-A, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2. Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 29% to $236,358 for the three
months ended March 31, 2001 as compared to $183,303 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
declines in production. For the three months ended March 31, 2001, 4,722 barrels
of oil, 1,543 barrels of natural gas liquids ("NGLs") and 11,838 mcf of gas were
sold, or 8,238 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 4,767 barrels of oil, 2,523 barrels of NGLs and 9,897 mcf of gas
were sold, or 8,940 BOEs.


                                        7
   1419



The average price received per barrel of oil increased $1.00, or 4%, from $27.38
for the three months ended March 31, 2000 to $28.38 for the same period in 2001.
The average price received per barrel of NGLs increased $5.61, or 41%, from
$13.78 for the three months ended March 31, 2000 to $19.39 for the same period
in 2001. The average price received per mcf of gas increased 236% from $1.82
during the three months ended March 31, 2000 to $6.12 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $105,172 for the three months ended March
31, 2001 as compared to $97,129 for the same period in 2000, an increase of
$8,043, or 8%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $76,877 for the three months ended March 31, 2001 and
$70,816 for the same period in 2000, resulting in a $6,061 increase, or 9%. This
increase was primarily due to higher production taxes associated with higher oil
and gas prices and additional well maintenance costs incurred to stimulate well
production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 51% from $5,681 for the three months ended March 31, 2000 to $8,561
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $19,734 for the three months ended March 31, 2001 as compared to
$20,632 for the same period in 2000, a decrease of $898, or 4%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $51,822 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $53,129 in oil and gas sales receipts
and a reduction of $7,634 in working capital, offset by increases in production
costs of $6,061 and G&A expenses of $2,880. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $61,531 to oil and gas receipts, offset by $8,402 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs


                                        8
   1420


incurred to stimulate well production. The increase in G&A was primarily due to
a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual of tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 were for expenditures related to oil and gas equipment
upgrades on active oil and gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $137,512, of which $1,375 was distributed to the managing general partner
and $136,137 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $87,388, of which $874 was distributed
to the managing general partner and $86,514 to the limited partners.

Proposal to acquire partnerships

On April 18, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement with the SEC proposing an agreement and plan of
merger among Pioneer, Pioneer Natural Resources USA, Inc. ("Pioneer USA"), a
wholly-owned subsidiary of Pioneer, and the limited partners of 46 Parker &
Parsley limited partnerships. Pioneer USA is the sole or managing general
partner of the partnerships. The preliminary proxy statement is non-binding and
is subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partners in each partnership and the resolution of SEC review comments. If
approved, Pioneer anticipates closing the mergers during the third quarter of
2001.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6. Exhibits and Reports on Form 8-K

(a)      Exhibits - none

(b)      Reports on Form 8-K - none.


                                        9
   1421


                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)


                                   SIGNATURES


         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 90-A, L.P.

                                     By:    Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 9, 2001                  By:    /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer


                                       10
   1422
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-26097-05


                           PARKER & PARSLEY 90-A, L.P.
             (Exact name of Registrant as specified in its charter)

                     DELAWARE                             75-2329245
        ----------------------------------         ------------------------
        (State or other jurisdiction of               (I.R.S. Employer
        incorporation or organization)             Identification Number)



                                                                               
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                      75039
----------------------------------------------------------------                  -------------
                     (Address of principal executive offices)                      (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES /X/ NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. /X/

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$6,664,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 6,811.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.




   1423

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 90-A, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 6,811 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers. Of the Partnership's total oil and
gas revenues for 2000, approximately 54%, 12% and 10% were attributable to sales
made to Plains Marketing, L.P., TEPPCO Crude Oil LLC and NGTS LLC, respectively.
Pioneer USA is of the opinion that the loss of any one purchaser would not have
an adverse effect on its ability to sell its oil, natural gas liquids ("NGLs")
and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial



                                       2
   1424

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 27
oil and gas wells. Two wells have been sold. At December 31, 2000, 25 wells were
producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                       3
   1425


                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
           DISTRIBUTIONS

At March 8, 2001, the Partnership had 6,811 outstanding limited partnership
interests held of record by 525 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $434,802 and $152,818, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                    2000           1999            1998            1997            1996
                                 ----------     -----------     -----------     ----------     -----------
                                                                                
Operating results:
-----------------
  Oil and gas sales              $  806,344     $   488,752     $   441,480     $  643,882     $   777,677
                                 ==========     ===========     ===========     ==========     ===========

  Impairment of oil and gas
    properties                   $      -       $       -       $    34,145     $  321,019     $       -
                                 ==========     ===========     ===========     ==========     ===========

  Net income (loss)              $  390,714     $    99,965     $   (44,421)    $ (149,948)    $   261,210
                                 ==========     ===========     ===========     ==========     ===========

  Allocation of net
    income (loss):
      Managing general partner   $    3,907     $     1,000     $      (444)    $   (1,499)    $     2,612
                                 ==========     ===========     ===========     ==========     ===========

      Limited partners           $  386,807     $    98,965     $   (43,977)    $ (148,449)    $   258,598
                                 ==========     ===========     ===========     ==========     ===========

  Limited partners' net income
    (loss) per limited
    partnership interest         $    56.79     $     14.53     $     (6.46)    $   (21.80)    $     37.97
                                 ==========     ===========     ===========     ==========     ===========

  Limited partners' cash
    distributions per limited
    partnership interest         $    63.84     $     22.44     $     28.44     $    53.06     $     53.75
                                 ==========     ===========     ===========     ==========     ===========

At year end:
-----------
  Identifiable assets            $1,285,569     $ 1,333,533     $ 1,385,777     $1,634,061     $ 2,146,498
                                 ==========     ===========     ===========     ==========     ===========




                                       4
   1426



ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
           RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 65% to $806,344 for 2000 as
compared to $488,752 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 18,065
barrels of oil, 10,454 barrels of natural gas liquids ("NGLs") and 38,570 mcf of
gas were sold, or 34,947 barrel of oil equivalents ("BOEs"). In 1999, 17,702
barrels of oil, 11,546 barrels of NGLs and 43,302 mcf of gas were sold, or
36,465 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.26, or 72% from
$17.06 in 1999 to $29.32 in 2000. The average price received per barrel of NGLs
increased $6.04, or 63% from $9.58 in 1999 to $15.62 in 2000. The average price
received per mcf of gas increased 67% in 2000 to $2.94 compared to $1.76 in
1999. The market price for oil and gas has been extremely volatile in the past
decade and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gain on disposition of assets of $9,419 was recognized during 2000 resulting
from equipment credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $433,960 as compared to $394,007
in 1999, an increase of $39,953, or 10%. This increase was primarily due to
increases in production costs and general and administrative expenses ("G&A"),
offset by a decline in depletion.

Production costs were $329,608 in 2000 and $269,017 in 1999, resulting in an
increase of $60,591, or 23%. The increase was primarily due to additional well
maintenance and workover costs incurred to stimulate well production and higher
production taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
36% from $20,244 in 1999 to $27,629 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $24,038 in 2000 and $14,514 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                       5
   1427



Depletion was $76,723 in 2000 compared to $104,746 in 1999, representing a
decrease of $28,023, or 27%. This decrease was primarily due to a 33,982 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 11% to $488,752 from
$441,480 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 17,702 barrels of oil,
11,546 barrels of NGLs and 43,302 mcf of gas were sold, or 36,465 BOEs. In 1998,
21,587 barrels of oil, 11,328 barrels of NGLs and 47,086 mcf of gas were sold,
or 40,763 BOEs.

The average price received per barrel of oil increased $3.86, or 29% from $13.20
in 1998 to $17.06 in 1999. The average price received per barrel of NGLs
increased $2.56, or 36% from $7.02 in 1998 to $9.58 in 1999. The average price
received per mcf of gas increased 7% in 1999 to $1.76 compared to $1.64 in 1998.

Total costs and expenses decreased in 1999 to $394,007 as compared to $492,078
in 1998, a decrease of $98,071, or 20%. This decrease was primarily due to
declines in depletion, the impairment of oil and gas properties and production
costs, offset by an increase in G&A.

Production costs were $269,017 in 1999 and $282,430 in 1998, resulting in a
$13,413 decline, or 5%. The decline includes a reduction in ad valorem taxes and
less well maintenance costs.

During this period, G&A increased 43% from $14,124 in 1998 to $20,244 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $14,514 in
1999 and $11,560 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $34,145 related to its oil and gas properties during 1998.

Depletion was $104,746 in 1999 compared to $161,379 in 1998. This represented a
decrease of $56,633, or 35%. This decrease was primarily the result of an
increase in proved reserves of 125,332 barrels of oil during 1999 as a result of
higher commodity prices, a reduction in the Partnership's net depletable basis
from charges taken in accordance with SFAS 121 during the fourth quarter of 1998
and a decline in oil production of 3,885 barrels for the period ended December
31, 1999 compared to the same period in 1998.




                                       6
   1428


Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $223,816 during the year
ended December 31, 2000 from 1999. This increase was due to increases in oil and
gas sales receipts of $321,283, offset by increases in production costs paid of
$60,591, G&A expenses paid of $7,385 and working capital of $29,491. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $341,604 to oil and gas receipts,
offset by $20,321 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's investing activities during 2000 and 1999 were for
expenditures related to oil and gas equipment upgrades on active properties.

Proceeds from asset dispositions of $9,419 were recognized during 2000 from
equipment credits on one fully depleted well and proceeds of $7,220 in 1999 were
from equipment credits received on one active property and one temporarily
abandoned property.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $439,194, of which $4,392 was
distributed to the managing general partner and $434,802 to the limited
partners. In 1999, cash distributions to the partners were $154,362 of which
$1,544 was distributed to the managing general partner and $152,818 to the
limited partners.



                                       7
   1429



ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----

                                                                                      
Financial Statements of Parker & Parsley 90-A, L.P.:
 Independent Auditors' Report.........................................................     9
 Balance Sheets as of December 31, 2000 and 1999......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14





                                       8
   1430


                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90-A, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90-A, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90-A, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                            Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       9
   1431


                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                      2000             1999
                                                   -----------      -----------

                                                              
              ASSETS
              ------

Current assets:
  Cash                                             $    92,685      $   122,649
  Accounts receivable - oil and gas sales              122,067           72,167
                                                   -----------      -----------

       Total current assets                            214,752          194,816
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method               5,085,185        5,076,362
Accumulated depletion                               (4,014,368)      (3,937,645)
                                                   -----------      -----------

       Net oil and gas properties                    1,070,817        1,138,717
                                                   -----------      -----------

                                                   $ 1,285,569      $ 1,333,533
                                                   ===========      ===========

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $    15,770      $    15,254

Partners' capital:
  Managing general partner                              12,779           13,264
  Limited partners (6,811 interests)                 1,257,020        1,305,015
                                                   -----------      -----------

                                                     1,269,799        1,318,279
                                                   -----------      -----------
                                                   $ 1,285,569      $ 1,333,533
                                                   ===========      ===========




   The accompanying notes are an integral part of these financial statements.



                                       10
   1432



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                2000         1999          1998
                                              --------     --------     ---------

                                                               
Revenues:
  Oil and gas                                 $806,344     $488,752     $ 441,480
  Interest                                       8,911        5,220         6,177
  Gain on disposition of assets                  9,419          -             -
                                              --------     --------     ---------

                                               824,674      493,972       447,657
                                              --------     --------     ---------

Costs and expenses:
  Oil and gas production                       329,608      269,017       282,430
  General and administrative                    27,629       20,244        14,124
  Impairment of oil and gas properties             -            -          34,145
  Depletion                                     76,723      104,746       161,379
                                              --------     --------     ---------

                                               433,960      394,007       492,078
                                              --------     --------     ---------

Net income (loss)                             $390,714     $ 99,965     $ (44,421)
                                              ========     ========     =========

Allocation of net income (loss):
  Managing general partner                    $  3,907     $  1,000     $    (444)
                                              ========     ========     =========

  Limited partners                            $386,807     $ 98,965     $ (43,977)
                                              ========     ========     =========

Net income (loss) per limited partnership
  interest                                    $  56.79     $  14.53     $   (6.46)
                                              ========     ========     =========




   The accompanying notes are an integral part of these financial statements.



                                       11
   1433



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL





                                           Managing
                                            general        Limited
                                            partner        partners           Total
                                           ---------     ------------     ------------

                                                                 
Partners' capital at January 1, 1998       $ 16,209      $ 1,596,562      $ 1,612,771

    Distributions                            (1,957)        (193,717)        (195,674)

    Net loss                                   (444)         (43,977)         (44,421)
                                           --------      -----------      -----------

Partners' capital at December 31, 1998       13,808        1,358,868        1,372,676

    Distributions                            (1,544)        (152,818)        (154,362)

    Net income                                1,000           98,965           99,965
                                           --------      -----------      -----------

Partners' capital at December 31, 1999       13,264        1,305,015        1,318,279

    Distributions                            (4,392)        (434,802)        (439,194)

    Net income                                3,907          386,807          390,714
                                           --------      -----------      -----------

Partners' capital at December 31, 2000     $ 12,779      $ 1,257,020      $ 1,269,799
                                           ========      ===========      ===========





   The accompanying notes are an integral part of these financial statements.



                                       12
   1434



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31






                                                         2000           1999           1998
                                                      ---------      ---------      ---------

                                                                           
Cash flows from operating activities:
  Net income (loss)                                   $ 390,714      $  99,965      $ (44,421)
  Adjustments to reconcile net income (loss) to
    net cash provided by operating activities:
      Impairment of oil and gas properties                  -              -           34,145
      Depletion                                          76,723        104,746        161,379
      Gain on disposition of assets                      (9,419)           -              -
  Changes in assets and liabilities:
      Accounts receivable                               (49,900)       (22,046)        37,507
      Accounts payable                                      516          2,153         (8,189)
                                                      ---------      ---------      ---------

        Net cash provided by operating activities       408,634        184,818        180,421
                                                      ---------      ---------      ---------

Cash flows from investing activities:
  Additions to oil and gas properties                    (8,823)        (7,237)        (9,047)
  Proceeds from asset dispositions                        9,419          7,220            -
                                                      ---------      ---------      ---------

        Net cash provided by (used in)
           investing activities                             596            (17)        (9,047)
                                                      ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                       (439,194)      (154,362)      (195,674)
                                                      ---------      ---------      ---------

Net increase (decrease) in cash                         (29,964)        30,439        (24,300)
Cash at beginning of year                               122,649         92,210        116,510
                                                      ---------      ---------      ---------

Cash at end of year                                   $  92,685      $ 122,649      $  92,210
                                                      =========      =========      =========




   The accompanying notes are an integral part of these financial statements.



                                       13
   1435



                           PARKER & PARSLEY 90-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 90-A, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.



                                       14
   1436

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $34,145 related to its
proved oil and gas properties during 1998.



                                       15
   1437

NOTE 4.    INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $315,080 greater than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                 2000          1999           1998
                                                              ---------      ---------      ---------

                                                                                   
Net income (loss) per statements of operations                $ 390,714      $  99,965      $ (44,421)
Depletion and depreciation provisions for tax
  reporting purposes less than amounts for
  financial reporting purposes                                   68,390         96,496        149,296
Impairment of oil and gas properties for financial
  reporting purposes                                                -              -           34,145
Other, net                                                       (1,209)         3,745          3,688
                                                              ---------      ---------      ---------

      Net income per Federal income tax
        returns                                               $ 457,895      $ 200,206      $ 142,708
                                                              =========      =========      =========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                     2000          1999           1998
                                                   ---------     ---------     ----------

                                                                      
      Development costs                            $   8,823     $   7,237     $    9,047
                                                   =========     =========     ==========


      Capitalized oil and gas properties consist of the following:



                                                                     2000          1999
                                                                  -----------    ----------
                                                                           
    Proved properties:
      Property acquisition costs                                  $   200,177    $   200,177
      Completed wells and equipment                                 4,885,008      4,876,185
                                                                  -----------    -----------

                                                                    5,085,185      5,076,362
    Accumulated depletion                                          (4,014,368)    (3,937,645)
                                                                  -----------    -----------

      Net oil and gas properties                                  $ 1,070,817    $ 1,138,717
                                                                  ===========    ===========


NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                     2000          1999           1998
                                                   ---------     ---------      ---------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 122,715     $ 120,620      $ 119,432
    Reimbursement of general and administrative
      expenses                                     $  24,038     $  14,514      $  11,560




                                       16
   1438

      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and P&P Employees 90-A, L.P., ("EMPL"), Parker & Parsley 90-A Conv., L.P. and
the Partnership (the "Partnerships") are parties to the Program agreement. EMPL
is a limited partnership organized for the benefit of certain employees of
Pioneer USA. EMPL was merged with Pioneer USA on December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                               Pioneer USA (1)   Partnerships (2)
                                                               ---------------   ----------------
                                                                           
    Revenues:
      Proceeds from disposition of depreciable and
        depletable properties -
          First three years                                      14.141414%         85.858586%
          After first three years                                19.191919%         80.808081%
      All other revenues -
          First three years                                      14.141414%         85.858586%
          After first three years                                19.191919%         80.808081%
    Costs and expenses:
      Lease acquisition costs, drilling and completion
        and all other costs                                       9.090909%         90.909091%
      Operating costs, reporting and legal expenses and
        general and administrative expenses -
          First three years                                      14.141414%         85.858586%
          After first three years                                19.191919%         80.808081%


    (1)  Excludes Pioneer USA's 1% general partner ownership which is allocated
         at the Partnership level and 147 limited partner interests owned by
         Pioneer USA.
    (2)  The allocation between the Partnership and Parker & Parsley 90-A
         Conv., L.P. is 74.274809% and 25.725191%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.






                                                              Oil and NGLs         Gas
                                                                 (bbls)            (mcf)
                                                              ------------      -----------

                                                                          
    Net proved reserves at January 1, 1998                        398,405          594,075
    Revisions                                                    (141,729)        (152,757)
    Production                                                    (32,915)         (47,086)
                                                              ------------      -----------
    Net proved reserves at December 31, 1998                      223,761          394,232
    Revisions                                                     206,682          351,371
    Production                                                    (29,248)         (43,302)
                                                              ------------      -----------
    Net proved reserves at December 31, 1999                      401,195          702,301
    Revisions                                                      21,424         (168,710)
    Production                                                    (28,519)         (38,570)
                                                              ------------      -----------
    Net proved reserves at December 31, 2000                      394,100          495,021
                                                               ==========       ==========



                                       17
   1439


      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.25 per barrel of NGLs and $7.89 per mcf of gas,
discounted at 10% was approximately $3,042,000 and undiscounted was $5,865,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

      The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

      Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                 For the years ended December 31,
                                                               -----------------------------------
                                                                 2000         1999          1998
                                                               --------      -------      -------
                                                                         (in thousands)
                                                                                 
Oil and gas producing activities:
  Future cash inflows                                          $ 12,560      $ 9,975      $ 2,464
  Future production costs                                        (6,695)      (5,908)      (1,931)
                                                               --------      -------      -------

                                                                  5,865        4,067          533
  10% annual discount factor                                     (2,823)      (1,884)        (155)
                                                               --------      -------      -------

  Standardized measure of discounted future net cash flows     $  3,042      $ 2,183      $   378
                                                               ========      =======      =======


                                                                 For the years ended December 31,
                                                               ------------------------------------
                                                                 2000          1999         1998
                                                               --------     ---------     --------
                                                                          (in thousands)
                                                                                 
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs                   $   (477)    $    (220)    $   (159)
  Net changes in prices and production costs                      1,267         1,209       (1,027)
  Revisions of previous quantity estimates                          (44)        1,476         (174)
  Accretion of discount                                             218            38          162
  Changes in production rates, timing and other                    (105)         (698)         (41)
                                                               --------     ---------     --------

  Change in present value of future net revenues                    859         1,805       (1,239)
                                                               --------     ---------     --------

  Balance, beginning of year                                      2,183           378        1,617
                                                               --------     ---------     --------

  Balance, end of year                                         $  3,042     $   2,183     $    378
                                                               ========     =========     ========




                                       18
   1440

NOTE 8.    MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
          Plains Marketing, L.P.                      54%            51%            -
          TEPPCO Crude Oil LLC                        12%            11%            -
          NGTS LLC                                    10%            10%            3%
          Western Gas Resources, Inc.                  2%             5%           22%
          Genesis Crude Oil, L.P.                      -              -            57%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
TEPPCO Crude Oil LLC and NGTS LLC were $37,832, $7,318 and $4,105, respectively,
which are included in the caption "Accounts receivable - oil and gas sales" in
the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the limited partnership agreement, the managing general partner pays
      1% of the Partnership's acquisition, drilling and completion costs and 1%
      of its operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.



                                       19
   1441

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of $6,811,000.
      Pioneer USA is required to contribute amounts equal to 1% of initial
      Partnership capital less commission and organization and offering costs
      allocated to the limited partners and to contribute amounts necessary to
      pay costs and expenses allocated to it under the Partnership agreement to
      the extent its share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
           FINANCIAL DISCLOSURE

None.



                                       20
   1442



                                    PART III


ITEM 10.    DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                      Age at
                                   December 31,
       Name                            2000                       Position
       ----                            ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   1443



      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.




                                       22
   1444



ITEM 11.    EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 15% during the first three years
and approximately 20% after three years of its operating and general and
administrative expenses. In return, they are allocated approximately 15% during
the first three years and approximately 20% after three years of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.    SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)   Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 147 limited partner interests at January 1, 2001.

(b)   Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.    CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                       23
   1445





                                                     2000          1999           1998
                                                   ---------     ---------      ---------

                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 122,715     $ 120,620      $ 119,432

    Reimbursement of general and administrative
      expenses                                     $  24,038     $  14,514      $  11,560


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.




                                       24
   1446



                                     PART IV

ITEM 14.    EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31,
                   2000, 1999 and 1998

                 Statements of partners' capital for the years ended December
                   31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31,
                   2000, 1999 and 1998

                 Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   1447



                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.


                                     PARKER & PARSLEY 90-A, L.P.

Dated:  March 28, 2001               By:  Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                -------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                        
/s/ Scott D. Sheffield              President of Pioneer USA                  March 28, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President. Chief           March 28, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 28, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 28, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic      March 28, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 28, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       26
   1448



                           PARKER & PARSLEY 90-A, L.P.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



    Exhibit No.                             Description                            Page
    -----------                             -----------                            ----

                                                                             
       3(a)               Form of Agreement of Limited Partnership                  -
                          of Parker & Parsley 90-A, L.P. incorporated
                          by reference to Exhibit A of the Post-Effective
                          Amendment No. 1 of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(b)               Form of Limited Partner Subscription Agreement            -
                          incorporated by reference to Exhibit C of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Form of General Partner Subscription Agreement            -
                          incorporated by reference to Exhibit D of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(b)               Power of Attorney incorporated by reference to            -
                          Exhibit B of Amendment No. 1 of the
                          Partnership's Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit 4c
                          of the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)

      10(b)               Form of Development Drilling Program                      -
                          Agreement incorporated by reference to Exhibit
                          B of the Post-Effective Amendment No. 1 of
                          the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)





                                       27
   1449



                           PARKER & PARSLEY 90-A, L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  183,303   $  806,344   $  488,752   $  441,480   $  643,882   $  777,677
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   34,145   $  321,019   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   87,757   $  390,714   $   99,965   $  (44,421)  $ (149,948)  $  261,210
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
      Managing general
         partner                   $          $      878   $    3,907   $    1,000   $     (444)  $   (1,499)  $    2,612
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $   86,879   $  386,807   $   98,965   $  (43,977)  $ (148,449)  $  258,598
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    12.76   $    56.79   $    14.53   $    (6.46)  $   (21.80)  $    37.97
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    12.70   $    63.84   $    22.44   $    28.44   $    53.06   $    53.75
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,334,248   $1,285,569   $1,333,533   $1,385,777   $1,634,061   $2,146,498
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1450

                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 90-B CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
90-B Conv., L.P., and supplements the proxy statement/prospectus dated         ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 90-B Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1451

                        PARKER & PARSLEY 90-B CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $  11,897

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $   8,765

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   3,131
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  264.97

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.16 times
past four quarterly distributions including the distribution in July 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  153.03

        --        as of December 31, 2000  (c)                                                 $  156.33

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  246.11

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  257.05

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     155
(c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2040, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.



                                      -2-
   1452



                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-26097-08


                        PARKER & PARSLEY 90-B CONV., L.P.
             (Exact name of Registrant as specified in its charter)

                   Delaware                            75-2329284
        -------------------------------          ---------------------
        (State or other jurisdiction of             (I.R.S. Employer
        incorporation or organization)           Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas     75039
----------------------------------------------------------------   ---------
           (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.


                                Yes [x]   No [ ]






   1453



                        PARKER & PARSLEY 90-B CONV., L.P.

                                TABLE OF CONTENTS




                                                                        Page
                                                                
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................   10

            Signatures...............................................   11





                                        2

   1454



                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                      March 31,     December 31,
                                                        2001            2000
                                                    ------------    ------------
                                                     (Unaudited)
                                                              
                 ASSETS

Current assets:
  Cash                                              $    131,173    $    132,300
  Accounts receivable - oil and gas sales                210,919         209,552
                                                    ------------    ------------
        Total current assets                             342,092         341,852
                                                    ------------    ------------
Oil and gas properties - at cost,  based on the
  successful efforts accounting method                 9,628,428       9,628,120
Accumulated depletion                                 (8,102,672)     (8,075,752)
                                                    ------------    ------------
        Net oil and gas properties                     1,525,756       1,552,368
                                                    ------------    ------------
                                                    $  1,867,848    $  1,894,220
                                                    ============    ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                      $     28,900    $     15,580

Partners' capital:
  Managing general partner                                18,388          18,785
  Limited partners (11,897 interests)                  1,820,560       1,859,855
                                                    ------------    ------------
                                                       1,838,948       1,878,640
                                                    ------------    ------------
                                                    $  1,867,848    $  1,894,220
                                                    ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3

   1455



                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                      Three months ended
                                                           March 31,
                                                  ---------------------------
                                                      2001           2000
                                                  ------------   ------------
                                                           
Revenues:
  Oil and gas                                     $    424,735   $    330,703
  Interest                                               2,507          2,093
  Gain on disposition of assets                          1,975          2,023
                                                  ------------   ------------
                                                       429,217        334,819
                                                  ------------   ------------
Costs and expenses:
  Oil and gas production                               143,206        133,608
  General and administrative                            13,562         10,132
  Depletion                                             26,920         26,760
                                                  ------------   ------------
                                                       183,688        170,500
                                                  ------------   ------------
Net income                                        $    245,529   $    164,319
                                                  ============   ============
Allocation of net income:
  Managing general partner                        $      2,455   $      1,643
                                                  ============   ============
  Limited partners                                $    243,074   $    162,676
                                                  ============   ============
Net income per limited partnership interest       $      20.43   $      13.67
                                                  ============   ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        4

   1456



                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                   Managing
                                    general        Limited
                                    partner        partners         Total
                                 ------------    ------------    ------------
                                                        
Balance at January 1, 2001       $     18,785    $  1,859,855    $  1,878,640

     Distributions                     (2,852)       (282,369)       (285,221)

     Net income                         2,455         243,074         245,529
                                 ------------    ------------    ------------

Balance at March 31, 2001        $     18,388    $  1,820,560    $  1,838,948
                                 ============    ============    ============







         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5

   1457


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                            Three months ended
                                                                 March 31,
                                                          ------------------------
                                                             2001          2000
                                                          ----------    ----------
                                                                  
Cash flows from operating activities:
   Net income                                             $  245,529    $  164,319
   Adjustments to reconcile net income to net
     cash provided by operating activities:
       Depletion                                              26,920        26,760
       Gain on disposition of assets                          (1,975)       (2,023)
   Changes in assets and liabilities:
       Accounts receivable                                    (1,367)      (20,130)
       Accounts payable                                       13,320         2,898
                                                          ----------    ----------
           Net cash provided by operating activities         282,427       171,824
                                                          ----------    ----------
Cash flows from investing activities:
   Additions to oil and gas properties                          (308)       (6,511)
   Proceeds from disposition of assets                         1,975         2,023
                                                          ----------    ----------
           Net cash provided by (used in) investing
             activities                                        1,667        (4,488)
                                                          ----------    ----------
Cash flows used in financing activities:
   Cash distributions to partners                           (285,221)     (180,055)
                                                          ----------    ----------
Net decrease in cash                                          (1,127)      (12,719)
Cash at beginning of period                                  132,300       132,031
                                                          ----------    ----------
Cash at end of period                                     $  131,173    $  119,312
                                                          ==========    ==========





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        6

   1458



                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 90-B Conv., L.P. (the "Partnership") was organized as a general
partnership in 1990 under the laws of the State of Texas and was converted to a
Delaware limited partnership on August 1, 1991.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 28% to $424,735 for the three
months ended March 31, 2001 as compared to $330,703 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 8,755
barrels of oil, 3,239 barrels of natural gas liquids ("NGLs") and 18,996 mcf of
gas were sold, or 15,160 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 8,990 barrels of oil, 3,979 barrels of NGLs and
15,621 mcf of gas were sold, or 15,573 BOEs.



                                        7

   1459



The average price received per barrel of oil increased $1.56, or 6%, from $27.70
for the three months ended March 31, 2000 to $29.26 for the same period in 2001.
The average price received per barrel of NGLs increased $4.36, or 31%, from
$13.89 for the three months ended March 31, 2000 to $18.25 for the same period
in 2001. The average price received per mcf of gas increased 243% from $1.68
during the three months ended March 31, 2000 to $5.76 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gains on disposition of assets of $1,975 and $2,023 was recognized during the
three months ended March 31, 2001 and 2000, respectively, from the sale of
equipment on one fully depleted well.

Costs and Expenses:

Total costs and expenses increased to $183,688 for the three months ended March
31, 2001 as compared to $170,500 for the same period in 2000, an increase of
$13,188, or 8%. The increase was due to increases in production costs and
general, administrative expenses ("G&A") and depletion.

Production costs were $143,206 for the three months ended March 31, 2001 and
$133,608 for the same period in 2000, resulting in a $9,598 increase, or 7%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 34% from $10,132 for the three months ended March 31, 2000 to $13,562
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $26,920 for the three months ended March 31, 2001 as compared to
$26,760 for the same period in 2000, an increase of $160. The increase was
primarily due to downward revisions to proved reserves on several wells during
the three months ended March 31, 2001, offset by a reduction in the
Partnership's net depletable basis from charges taken in accordance with
Statement of Financial Accounting Standards No. 121, "Accounting for the
Impairment of Long-Lived Assets and for Long-Lived Assets to be Disposed Of"
("SFAS 121") during the fourth quarter of 2000 and a decline in oil production
of 235 barrels for the period ended March 31, 2001 compared to the same period
in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $110,603 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $94,446 in oil and gas sales receipts
and a reduction in working capital of $29,185, offset by increases in production
costs of $9,598 and G&A expenses of $3,430. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an



                                        8

   1460



additional $95,426 to oil and gas receipts, offset by $980 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices. The increase in G&A was primarily due
to a higher percentage of the managing general partner's G&A being allocated
(limited to 3% of oil and gas revenues) as a result of increased oil and gas
revenues and an increase in the accrual for tax preparation fees.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities for the three months ended
March 31, 2001 and 2000 were for expenditures related to oil and gas equipment
upgrades on active properties.

Proceeds from disposition of assets of $1,975 and $2,023 received during the
three months ended March 31, 2001 and 2000, respectively, were derived from the
sale of equipment on one fully depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $285,221, of which $2,852 was distributed to the managing general partner
and $282,369 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $180,055, of which $1,801 was
distributed to the managing general partner and $178,254 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.



                                        9

   1461



                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)      Exhibits - none

(b)      Reports on Form 8-K - none.





                                       10

   1462


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                           PARKER & PARSLEY 90-B CONV., L.P.


                                  By:      Pioneer Natural Resources USA, Inc.
                                            Managing General Partner



Dated:  May 11, 2001              By:      /s/ Rich Dealy
                                           -----------------------------------
                                           Rich Dealy, Vice President
                                             and Chief Accounting Officer









                                       11



   1463
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-26097-08


                        PARKER & PARSLEY 90-B CONV., L.P.
             (Exact name of Registrant as specified in its charter)

         DELAWARE                                           75-2329284
-------------------------------                     --------------------------
(State or other jurisdiction of                          (I.R.S. Employer
incorporation or organization)                         Identification Number)



                                                                                
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                      75039
----------------------------------------------------------------                  -------------
          (Address of principal executive offices)                                  (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$11,817,000.

           As of March 8, 2001, the number of outstanding limited partnership
interests was 11,897.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None
PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.
   1464



                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 90-B Conv., L.P. (the "Partnership") was organized in 1990 as a
general partnership under the laws of the State of Texas. The Partnership
converted to a Delaware limited partnership on August 1, 1991. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 11,897 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 48% was attributable to sales made to
Plains Marketing, L.P., 10% to TEPPCO Crude Oil LLC and 10% to Phillips
Petroleum Company. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or



                                       2
   1465

other liabilities and compliance may increase the cost of the Partnership's
operations. The oil and gas business is also subject to environmental hazards
such as oil spills, gas leaks and ruptures and discharges of toxic substances or
gases that could expose the Partnership to substantial liability due to
pollution and other environmental damages. Although the Partnership believes
that its business operations do not impair environmental quality and that its
costs of complying with any applicable environmental regulations are not
currently significant, the Partnership cannot predict what, if any, effect these
environmental regulations may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 104
oil and gas wells. One well has been plugged and abandoned. At December 31,
2000, the Partnership had 103 producing oil and gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.


                                     PART II


                                       3
   1466




ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
             DISTRIBUTIONS

At March 8, 2001, the Partnership had 11,897 outstanding limited partnership
interests held of record by 665 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $825,165 and $271,636, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                                   2000          1999          1998          1997             1996
                                              -----------   -----------   -----------   -----------    -------------
                                                                                        
Operating results:
------------------
  Oil and gas sales                           $ 1,513,122   $   907,791   $   764,787   $ 1,118,628    $   1,382,265
                                              ===========   ===========   ===========   ===========    =============

  Impairment of oil and gas
     properties                               $    31,774   $    88,497   $   275,430   $   328,594    $      22,474
                                              ===========   ===========   ===========   ===========    =============

  Net income (loss)                           $   787,438   $   164,414   $  (373,956)  $   (55,191)   $     544,919
                                              ===========   ===========   ===========   ===========    =============

  Allocation of net income
   (loss):
    Managing general partner                  $     7,874   $     1,644   $    (3,740)  $      (552)   $       5,449
                                              ===========   ===========   ===========   ===========    =============

    Limited partners                          $   779,564   $   162,770   $  (370,216)   $ (54,639)    $     539,470
                                              ===========   ===========   ===========   ===========    =============

  Limited partners' net income
    (loss) per limited
    partnership interest                      $     65.53   $     13.68   $    (31.12)  $     (4.59)   $       45.35
                                              ===========   ===========   ===========   ===========    =============

  Limited partners' cash
    distributions per limited
    partnership interest                      $     69.36   $     22.83   $     23.66   $     52.38    $       56.21
                                              ===========   ===========   ===========   ===========    =============

At year end:
------------
  Identifiable assets                         $ 1,894,220   $ 1,949,209   $ 2,057,408   $ 2,727,510    $   3,402,932
                                              ===========   ===========   ===========   ===========    =============





                                       4
   1467


ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
             RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 67% to $1,513,122 for 2000 as
compared to $907,791 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 36,592
barrels of oil, 16,796 barrels of natural gas liquids ("NGLs") and 64,786 mcf of
gas were sold, or 64,186 barrel of oil equivalents ("BOEs"). In 1999, 36,383
barrels of oil, 17,481 barrels of NGLs and 70,803 mcf of gas were sold, or
65,665 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.00, or 70%, from
$17.23 in 1999 to $29.23 in 2000. The average price received per barrel of NGLs
increased $5.96, or 63%, from $9.49 in 1999 to $15.45 in 2000. The average price
received per mcf of gas increased 75% from $1.62 in 1999 to $2.84 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $2,023 recognized in 2000 was due to
equipment credits received on one fully depleted well.

Total costs and expenses decreased to $739,327 in 2000 as compared to $749,072
in 1999, a decrease of $9,745, or 1%. The decrease was due to declines in the
impairment of oil and gas properties and depletion, offset by increases in
production costs and general and administrative expenses ("G&A").

Production costs were $557,245 in 2000 and $478,183 in 1999, resulting in an
increase of $79,062, or 17%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
and workover costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
30% from $35,038 in 1999 to $45,379 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $40,368 in 2000 and $27,181 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.




                                       5
   1468


In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized
non-cash charges of $31,774 and $88,497 related to its oil and gas properties
during 2000 and 1999, respectively.

Depletion was $104,929 in 2000 compared to $147,354 in 1999, representing a
decrease of $42,425, or 29%. The decrease was primarily due to a 27,994 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices and a reduction in the Partnership's net depletable basis from charges
taken in accordance with SFAS 121 during the fourth quarter of 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 19% to $907,791 from
$764,787 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 36,383 barrels of oil,
17,481 barrels of NGLs and 70,803 mcf of gas were sold, or 65,665 BOEs. In 1998,
41,140 barrels of oil, 17,403 barrels of NGLs and 73,460 mcf of gas were sold,
or 70,786 BOEs.

The average price received per barrel of oil increased $4.11, or 31%, from
$13.12 in 1998 to $17.23 in 1999. The average price received per barrel of NGLs
increased $2.89, or 44%, from $6.60 in 1998 to $9.49 in 1999. The average price
received per mcf of gas increased 8% from $1.50 in 1998 to $1.62 in 1999.

Gain on disposition of assets of $1,669 for 1998 was attributable to credits
received from the disposal of oil and gas equipment on a fully depleted well and
on one well that was plugged and abandoned in a prior year.

Total costs and expenses decreased to $749,072 in 1999 as compared to $1,147,349
in 1998, a decrease of $398,277, or 35%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $478,183 in 1999 and $517,526 in 1998, resulting in a
$39,343 decrease, or 8%. The decrease was due to declines in well maintenance
costs, ad valorem taxes and workover costs, offset by an increase in production
taxes due to increased oil and gas sales.

During this period, G&A increased 31% from $26,722 in 1998 to $35,038 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $27,181 in
1999 and $22,923 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $88,497 and $275,430
related to its oil and gas properties during 1999 and 1998, respectively.





                                       6
   1469


Depletion was $147,354 in 1999 compared to $327,671 in 1998. This represented a
decrease of $180,317, or 55%. The decrease was primarily due to an increase in
proved reserves of 280,631 barrels of oil during 1999 as a result of higher
commodity prices, a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998 and
a decline in oil production of 4,757 barrels for the period ended December 31,
1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $504,622 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $611,256, offset by increases in production costs paid
of $79,062, G&A expenses paid of $10,341 and working capital of $17,231. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $632,790 to oil and gas receipts,
offset by $21,534 resulting from the decline in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance and
workover costs incurred to stimulate well production. The increase in G&A was
primarily due to higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active oil and gas properties.

Proceeds from disposition of assets of $2,023 recognized in 2000 were due to
equipment credits received on one fully depleted well.





                                       7
   1470


Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $833,500, of which $8,335 was
distributed to the managing general partner and $825,165 to the limited
partners. In 1999, cash distributions to the partners were $274,380, of which
$2,744 was distributed to the managing general partner and $271,636 to the
limited partners.







                                       8
   1471


ITEM 8.      FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                         INDEX TO FINANCIAL STATEMENTS


                                                                                         Page
                                                                                         ----

                                                                                       
Financial Statements of Parker & Parsley 90-B Conv., L.P.:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15





                                       9
   1472



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90-B Conv., L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90-B Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90-B Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001






                                       10
   1473


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                   2000             1999
                                                               -----------      ----------
              ASSETS
              ------
                                                                          
Current assets:
  Cash                                                         $   132,300     $   132,031
  Accounts receivable - oil and gas sales                          209,552         143,411
                                                                 ---------       ---------

        Total current assets                                       341,852         275,442
                                                                 ---------       ---------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                           9,628,120       9,612,816
Accumulated depletion                                           (8,075,752)     (7,939,049)
                                                                 ---------       ---------

        Net oil and gas properties                               1,552,368       1,673,767
                                                                 ---------       ---------

                                                               $ 1,894,220     $ 1,949,209
                                                                ==========       =========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                 $    15,580     $    24,507

Partners' capital:
  Managing general partner                                          18,785          19,246
  Limited partners (11,897 interests)                            1,859,855       1,905,456
                                                                 ---------       ---------

                                                                 1,878,640       1,924,702
                                                                 ---------       ---------
                                                               $ 1,894,220     $ 1,949,209
                                                                 =========       =========









   The accompanying notes are an integral part of these financial statements.



                                       11
   1474


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                             2000          1999          1998
                                         -----------   -----------   -----------
                                                            
Revenues:
  Oil and gas                            $ 1,513,122   $   907,791   $   764,787
  Interest                                    11,620         5,695         6,937
  Gain on disposition of assets                2,023            --         1,669
                                         -----------   -----------   -----------

                                           1,526,765       913,486       773,393
                                         -----------   -----------   -----------

Costs and expenses:
  Oil and gas production                     557,245       478,183       517,526
  General and administrative                  45,379        35,038        26,722
  Impairment of oil and gas properties        31,774        88,497       275,430
  Depletion                                  104,929       147,354       327,671
                                         -----------   -----------   -----------

                                             739,327       749,072     1,147,349
                                         -----------   -----------   -----------

Net income (loss)                        $   787,438   $   164,414   $  (373,956)
                                         ===========   ===========   ===========

Allocation of net income (loss):
  Managing general partner               $     7,874   $     1,644   $    (3,740)
                                         ===========   ===========   ===========

  Limited partners                       $   779,564   $   162,770   $  (370,216)
                                         ===========   ===========   ===========

Net income (loss) per limited
  partnership interest                   $     65.53   $     13.68   $    (31.12)
                                         ===========   ===========   ===========



















   The accompanying notes are an integral part of these financial statements.



                                       12
   1475


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL





                                                     Managing
                                                      general       Limited
                                                      partner       partners         Total
                                                  -------------- -------------- ----------------

                                                                       
Partners' capital at January 1, 1998              $  26,929      $2,666,043     $2,692,972

   Distributions                                     (2,843)       (281,505)      (284,348)

   Net loss                                          (3,740)       (370,216)      (373,956)
                                                    -------        --------       --------

Partners' capital at December 31, 1998               20,346       2,014,322      2,034,668

   Distributions                                     (2,744)       (271,636)      (274,380)

   Net income                                         1,644         162,770        164,414
                                                    -------        --------       --------

Partners' capital at December 31, 1999               19,246       1,905,456      1,924,702

   Distributions                                     (8,335)       (825,165)      (833,500)

   Net income                                         7,874         779,564        787,438
                                                    -------        --------       --------

Partners' capital at December 31, 2000            $  18,785      $1,859,855     $1,878,640
                                                   ========       =========      =========















   The accompanying notes are an integral part of these financial statements.



                                       13
   1476


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                         2000         1999         1998
                                                       ---------    ---------    ---------

                                                                        
Cash flows from operating activities:
   Net income (loss)                                   $ 787,438    $ 164,414    $(373,956)
   Adjustments to reconcile net income (loss)
     to net cash provided by operating
     activities:
       Impairment of oil and gas properties               31,774       88,497      275,430
       Depletion                                         104,929      147,354      327,671
       Gain on disposition of assets                      (2,023)          --       (1,669)
   Changes in assets and liabilities:
       Accounts receivable                               (66,141)     (59,604)      42,963
       Accounts payable                                   (8,927)       1,767      (11,798)
                                                       ---------    ---------    ---------

           Net cash provided by operating activities     847,050      342,428      258,641
                                                       ---------    ---------    ---------

Cash flows from investing activities:
   Additions to oil and gas properties                   (15,304)     (12,347)     (18,344)
   Proceeds from disposition of assets                     2,023           --        1,669
                                                       ---------    ---------    ---------

           Net cash used in investing activities         (13,281)     (12,347)     (16,675)
                                                       ---------    ---------    ---------

Cash flows used in financing activities:
   Cash distributions to partners                       (833,500)    (274,380)    (284,348)
                                                       ---------    ---------    ---------

Net increase (decrease) in cash                              269       55,701      (42,382)
Cash at beginning of year                                132,031       76,330      118,712
                                                       ---------    ---------    ---------

Cash at end of year                                    $ 132,300    $ 132,031    $  76,330
                                                       =========    =========    =========








   The accompanying notes are an integral part of these financial statements.



                                       14
   1477


                        PARKER & PARSLEY 90-B CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 90-B Conv., L.P. (the "Partnership") was organized as a
general partnership in 1990 under the laws of the State of Texas and was
converted to a Delaware limited partnership on August 1, 1991. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       15
   1478

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $31,774, $88,497 and
$275,430 related to its proved oil and gas properties during 2000, 1999 and
1998, respectively.



                                       16
   1479

NOTE 4.    INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $233,211 greater than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                           2000         1999         1998
                                                         ---------    ---------    ---------

                                                                          
    Net income (loss) per statements of operations       $ 787,438    $ 164,414    $(373,956)
    Depletion and depreciation provisions for tax
      reporting purposes less than amounts for
      financial reporting purposes                          90,499      132,570      175,500
    Impairment of oil and gas properties for financial
      reporting purposes                                    31,774       88,497      275,430
    Other, net                                              (1,742)      (4,660)       3,987
                                                         ---------    ---------    ---------

        Net income per Federal income tax
          returns                                        $ 907,969    $ 380,821    $  80,961
                                                         =========    =========    =========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                   ----------- -------------- --------------
                                                                       
    Development costs                              $  15,304     $  12,347      $  18,344
                                                    ========      ========       ========


      Capitalized oil and gas properties consist of the following:



                                                                  2000              1999
                                                               ------------      -----------
    Proved properties:
                                                                           
      Property acquisition costs                               $  369,498        $  369,498
      Completed wells and equipment                             9,258,622         9,243,318
                                                                ---------         ---------

                                                                9,628,120         9,612,816
    Accumulated depletion                                      (8,075,752)       (7,939,049)
                                                               ----------        ----------

      Net oil and gas properties                               $1,552,368        $1,673,767
                                                               ==========        ==========


NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                        2000          1999           1998
                                                   ---------------------------- --------------
                                                                       
      Payment of lease operating and supervision
        charges in accordance with standard
        industry operating agreements              $ 211,037     $ 214,306      $ 209,549

      Reimbursement of general and administrative
        expenses                                   $  40,368     $  27,181      $  22,923


                                       17



   1480

      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 90-B Conv., L.P. ("EMPL"), Parker & Parsley 90-B, L.P. and the
Partnership (the "Partnerships") are parties to the Program agreement. EMPL is a
limited partnership organized for the benefit of certain employees of Pioneer
USA. EMPL was merged with Pioneer USA on December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                              Pioneer USA(1)    Partnerships(2)
                                                              --------------    ---------------
                                                                           
  Revenues:
    Proceeds from disposition of depreciable and
      depletable properties:
      First three years                                         14.141414%       85.858586%
      After first three years                                   19.191919%       80.808081%
    All other revenues
      First three years                                         14.141414%       85.858586%
      After first three years                                   19.191919%       80.808081%
  Costs and expenses:
    Lease acquisition costs, drilling and completion
      costs and all other costs                                  9.090909%       90.909091%
    Operating costs, reporting and legal expenses and
      general and administrative expenses:
      First three years                                         14.141414%       85.858586%
      After first three years                                   19.191919%       80.808081%


      (1)   Excludes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 80 limited partner interests
            owned by Pioneer USA.

      (2)   The allocation between the Partnership and Parker & Parsley 90-B,
            L.P. is 26.94006% and 73.05994%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                                               Oil and NGLs         Gas
                                                                  (bbls)           (mcf)
                                                              --------------    -----------
                                                                           
    Net proved reserves at January 1, 1998                       914,930           864,646
    Revisions                                                   (446,456)         (190,771)
    Production                                                   (58,543)          (73,460)
                                                                --------          --------

    Net proved reserves at December 31, 1998                     409,931           600,415
    Revisions                                                    435,645           666,249
    Production                                                   (53,864)          (70,803)
                                                                --------          --------

    Net proved reserves at December 31, 1999                     791,712         1,195,861
    Revisions                                                     15,019          (155,368)
    Production                                                   (53,388)          (64,786)
                                                                --------          --------

    Net proved reserves at December 31, 2000                     753,343           975,707
                                                                ========          ========




                                       18
   1481

      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.19 per barrel of NGLs and $7.66 per mcf of gas,
discounted at 10% was approximately $5,752,000 and undiscounted was $11,644,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.





                                                             For the years ended December 31,
                                                           ------------------------------------
                                                               2000        1999        1998
                                                             --------    --------    --------
                                                                      (in thousands)
                                                                            
Oil and gas producing activities:
  Future cash inflows                                        $ 24,248    $ 19,527    $  4,449
  Future production costs                                     (12,604)    (10,978)     (3,339)
                                                             --------    --------    --------
                                                               11,644       8,549       1,110
  10% annual discount factor                                   (5,892)     (4,165)       (375)
                                                             --------    --------    --------

  Standardized measure of discounted future net cash flows   $  5,752    $  4,384    $    735
                                                             ========    ========    ========




                                       19
   1482



                                                           For the years ended December 31,
                                                       --------------------------------------
                                                          2000         1999           1998
                                                        --------     ---------     --------
                                                                 (in thousands)
                                                                         
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs         $     (956)  $      (430)  $     (247)
    Net changes in prices and production costs              2,152         2,137       (2,389)
    Revisions of previous quantity estimates                  (71)        3,126         (518)
    Accretion of discount                                     438            74          362
    Changes in production rates, timing and other            (195)       (1,258)         (94)
                                                         --------     ---------     --------

    Change in present value of future net revenues          1,368         3,649       (2,886)
                                                         --------     ---------     --------

    Balance, beginning of year                              4,384           735        3,621
                                                         --------     ---------     --------

    Balance, end of year                               $    5,752   $     4,384   $      735
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

  The following table reflects the major customers of the Partnership's oil and
gas sales (a major customer is defined as a customer whose sales exceed 10% of
total sales) during the years ended December 31:


                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
           Plains Marketing, L.P.                     48%            46%            -
           TEPPCO Crude Oil LLC                       10%            11%            -
           Genesis Crude Oil, L.P.                     -              -            58%
           Western Gas Resources, Inc.                 4%             5%           21%
           Phillips Petroleum Company                 10%             5%            5%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
TEPPCO Crude Oil LLC and Phillips Petroleum Company were $65,440, $13,643 and
$7,386, respectively, which are included in the caption "Accounts receivable -
oil and gas sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.


NOTE 9.       PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
Partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The



                                       20
   1483

      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the Partnership agreement, the managing general partner pays 1% of
      the Partnership's acquisition, drilling and completion costs and 1% of its
      operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The partners entered into subscription
      agreements for aggregate capital contributions of $11,897,000. The
      managing general partner is required to contribute amounts equal to 1% of
      initial Partnership capital less commission and organization and offering
      costs allocated to the limited partners and to contribute amounts
      necessary to pay costs and expenses allocated to it under the Partnership
      agreement to the extent its share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
             AND FINANCIAL DISCLOSURE

None.



                                       21
   1484


                                    PART III


ITEM 10.   DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                     December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       22
   1485


      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.




                                       23
   1486


ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 15% during the first three years
and approximately 20% after three years of its operating and general and
administrative expenses. In return, they are allocated approximately 15% during
the first three years and approximately 20% after three years of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 80 limited partnership interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:






                                       24
   1487




                                                        2000          1999           1998
                                                   ---------------------------- --------------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 211,037     $ 214,306      $ 209,549

    Reimbursement of general and administrative
      expenses                                     $  40,368     $  27,181      $  22,923


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.



                                       25
   1488


                                     PART IV

ITEM 14.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

               Independent Auditors' Report

               Balance sheets as of December 31, 2000 and 1999

               Statements of operations for the years ended December 31, 2000,
                 1999 and 1998

               Statements of partners' capital for the years ended December 31,
                 2000, 1999 and 1998

               Statements of cash flows for the years ended December 31, 2000,
                 1999 and 1998

               Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       26
   1489


                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                      PARKER & PARSLEY 90-B CONV., L.P.

Dated: March 28, 2001           By:   Pioneer Natural Resources USA, Inc.
                                       Managing General Partner


                                      By:   /s/ Scott D. Sheffield
                                            ---------------------------------
                                            Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                       
/s/ Scott D. Sheffield              President of Pioneer USA                  March 28, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                 Executive Vice President, Chief           March 28, 2001
-------------------------------     Financial Officer and Director of
Timothy L. Dove                     Pioneer USA


/s/ Dennis E. Fagerstone            Executive Vice President and              March 28, 2001
-------------------------------     Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                 Executive Vice President, General         March 28, 2001
-------------------------------     Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                    Executive Vice President - Domestic       March 28, 2001
-------------------------------     Operations and Director of Pioneer
Danny Kellum                        USA


/s/ Rich Dealy                      Vice President and Chief Accounting       March 28, 2001
-------------------------------     Officer of Pioneer USA
Rich Dealy




                                       27
   1490


                        PARKER & PARSLEY 90-B CONV., L.P.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



     Exhibit No.                         Description                              Page
     -----------                         -----------                              ----

                                                                         
       3(a)               Form of Agreement of Limited Partnership                  -
                          of Parker & Parsley 90-B Conv., L.P.
                          incorporated by reference to Exhibit A of
                          the Post-Effective Amendment No. 1 of
                          the Partnership's Registration Statement
                          on Form S-1 (Registration No. 33-26097)

       4(b)               Form of Limited Partner Subscription Agreement            -
                          incorporated by reference to Exhibit C of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Form of General Partner Subscription Agreement            -
                          incorporated by reference to Exhibit D of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Power of Attorney incorporated by reference to            -
                          Exhibit B of Amendment No. 1 of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit 4c
                          of the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)

      10(b)               Form of Development Drilling Program                      -
                          Agreement incorporated by reference to Exhibit
                          B of the Post-Effective Amendment No. 1 of
                          the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)






                                       28




   1491




                        PARKER & PARSLEY 90-B CONV., L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  330,703   $1,513,122   $  907,791   $  764,787   $1,118,628   $1,382,265
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
     gas properties                $          $       --   $   31,774   $   88,497   $  275,430   $  328,594   $   22,474
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  164,319   $  787,438   $  164,414   $ (373,956)  $  (55,191)  $  544,919
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
   (loss):
      Managing general
        partner                    $          $    1,643   $    7,874   $    1,644   $   (3,740)  $     (552)  $    5,449
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  162,676   $  779,564   $  162,770   $ (370,216)  $  (54,639)  $  539,470
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
    (loss) per limited
    partnership interest           $          $    13.67   $    65.53   $    13.68   $   (31.12)  $    (4.59)  $    45.35
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    14.98   $    69.36   $    22.83   $    23.66   $    52.38   $    56.21
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,936,371   $1,894,220   $1,949,209   $2,057,408   $2,727,510   $3,402,932
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1492
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 90-B, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                 THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
90-B, L.P., and supplements the proxy statement/prospectus dated      , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 90-B, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1493

                           PARKER & PARSLEY 90-B, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                            
Aggregate Initial Investment by the Limited Partners  (a)                                      $  32,264

Aggregate Historical Limited Partner Distributions through July 31, 2001  (a)                  $  23,772

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   8,540
USA  (a), (b)

Merger Value per $1,000 Limited Partner Investment  (b), (c)                                   $  265.39

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the           3.18 times
past four quarterly distributions including the distribution in 2001  (b), (c)

Book Value per $1,000 Limited Partner Investment:

        --        as of March 31, 2001  (c)                                                    $  153.28

        --        as of December 31, 2000  (c)                                                 $  156.56

Going Concern Value per $1,000 Limited Partner Investment  (c), (d)                            $  246.52

Liquidation Value per $1,000 Limited Partner Investment  (c), (e)                              $  257.46

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment          $     155
(c), (f)



-----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2040, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.



                                      -2-
   1494

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-26097-07


                           PARKER & PARSLEY 90-B, L.P.
             (Exact name of Registrant as specified in its charter)

                        Delaware                              75-2329287
            ----------------------------------          ---------------------
             (State or other jurisdiction of               (I.R.S. Employer
             incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]







   1495



                           PARKER & PARSLEY 90-B, L.P.

                                TABLE OF CONTENTS




                                                                        Page

                                                                      
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................   10

            Signatures...............................................   11



                                        2

   1496



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS




                                                    March 31,     December 31,
                                                      2001            2000
                                                  ------------    ------------
                                                  (Unaudited)

                                                            
                 ASSETS
Current assets:
  Cash                                             $   361,118     $   364,895
  Accounts receivable - oil and gas sales              573,575         568,283
                                                   -----------     -----------
        Total current assets                           934,693         933,178
                                                   -----------     -----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              26,111,764      26,110,930
Accumulated depletion                              (21,972,352)    (21,899,717)
                                                   -----------     -----------
        Net oil and gas properties                   4,139,412       4,211,213
                                                   -----------     -----------
                                                   $ 5,074,105     $ 5,144,391
                                                   ===========     ===========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                     $    78,664     $    42,091

Partners' capital:
  Managing general partner                              49,958          51,027
  Limited partners (32,264 interests)                4,945,483       5,051,273
                                                   -----------     -----------
                                                     4,995,441       5,102,300
                                                   -----------     -----------
                                                   $ 5,074,105     $ 5,144,391
                                                   ===========     ===========




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.

                                        3

   1497
                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                        Three months ended
                                                             March 31,
                                                     -------------------------
                                                        2001           2000
                                                     ----------     ----------

                                                              
Revenues:
  Oil and gas                                        $1,151,858      $ 896,935
  Interest                                                7,085          5,740
  Gain on disposition of assets                           5,357          5,487
                                                      ---------      ---------
                                                      1,164,300        908,162
                                                      ---------      ---------
Costs and expenses:
  Oil and gas production                                388,370        362,344
  General and administrative                             36,650         27,481
  Depletion                                              72,635         72,621
                                                      ---------      ---------
                                                        497,655        462,446
                                                      ---------      ---------
Net income                                            $ 666,645      $ 445,716
                                                      =========      =========
Allocation of net income:
  Managing general partner                            $   6,666      $   4,457
                                                      =========      =========
  Limited partners                                    $ 659,979      $ 441,259
                                                      =========      =========
Net income per limited partnership interest           $   20.46      $   13.68
                                                      =========      =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   1498



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)






                                  Managing
                                  general          Limited
                                  partner          partners           Total
                                -----------       -----------       -----------


                                                           
Balance at January 1, 2001      $    51,027       $ 5,051,273       $ 5,102,300

    Distributions                    (7,735)         (765,769)         (773,504)

    Net income                        6,666           659,979           666,645
                                -----------       -----------       -----------

Balance at March 31, 2001       $    49,958       $ 4,945,483       $ 4,995,441
                                ===========       ===========       ===========






         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   1499
                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                          Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
    Net income                                          $ 666,645     $ 445,716
    Adjustments to reconcile net income to net
      cash provided by operating activities:
          Depletion                                        72,635        72,621
          Gain on disposition of assets                    (5,357)       (5,487)
    Changes in assets and liabilities:
          Accounts receivable                              (5,292)       (1,964)
          Accounts payable                                 36,573         7,992
                                                        ---------     ---------
          Net cash provided by operating activities       765,204       518,878
                                                        ---------     ---------
Cash flows from investing activities:
    Additions to oil and gas properties                      (834)      (17,655)
    Proceeds from disposition of assets                     5,357         5,487
                                                        ---------     ---------
          Net cash provided by (used in) investing
            activities                                      4,523       (12,168)
                                                        ---------     ---------
Cash flows used in financing activities:
    Cash distributions to partners                       (773,504)     (488,299)
                                                        ---------     ---------
Net increase (decrease) in cash                            (3,777)       18,411
Cash at beginning of period                               364,895       311,017
                                                        ---------     ---------
Cash at end of period                                   $ 361,118     $ 329,428
                                                        =========     =========



         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   1500



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 90-B, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 28% to $1,151,858 for the three
months ended March 31, 2001 as compared to $896,935 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 23,737
barrels of oil, 8,809 barrels of natural gas liquids ("NGLs") and 51,504 mcf of
gas were sold, or 41,130 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 24,387 barrels of oil, 10,810 barrels of NGLs and
42,382 mcf of gas were sold, or 42,261 BOEs.

                                        7

   1501



The average price received per barrel of oil increased $1.56, or 6%, from $27.70
for the three months ended March 31, 2000 to $29.26 for the same period in 2001.
The average price received per barrel of NGLs increased $4.36, or 31%, from
$13.89 for the three months ended March 31, 2000 to $18.25 for the same period
in 2001. The average price received per mcf of gas increased 243% from $1.68
during the three months ended March 31, 2000 to $5.76 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Gains on disposition of assets of $5,357 and $5,487 recognized during the three
months ended March 31, 2001 and 2000, respectively, were from the sale of
equipment on one fully depleted well.

Costs and Expenses:

Total costs and expenses increased to $497,655 for the three months ended March
31, 2001 as compared to $462,446 for the same period in 2000, an increase of
$35,209, or 8%. The increase was due to increases in production costs, general
and administrative expenses ("G&A") and depletion.

Production costs were $388,370 for the three months ended March 31, 2001 and
$362,344 for the same period in 2000, resulting in a $26,026 increase, or 7%.
The increase was primarily due to higher production taxes associated with higher
oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 33% from $27,481 for the three months ended March 31, 2000 to $36,650
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $72,635 for the three months ended March 31, 2001 as compared to
$72,621 for the same period in 2000, an increase of $14. The increase was
primarily due to downward revisions to proved reserves on several wells during
the three months ended March 31, 2001, offset by a reduction in the
Partnership's net depletable basis from charges taken in accordance with
Statement of Financial Accounting Standards No. 121, "Accounting for the
Impairment of Long-Lived Assets and for Long-Lived Assets to be Disposed Of"
("SFAS 121") during the fourth quarter of 2000 and a decline in oil production
of 650 barrels for the period ended March 31, 2001 compared to the same period
in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $246,326 for the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $256,268 in oil and gas sales receipts
and a reduction in working capital of $25,253, offset by increases in production
costs of $26,026 and G&A expenses of $9,169. The increase in oil and gas

                                        8

   1502



receipts resulted from the increase in commodity prices during 2001 which
contributed an additional $259,260 to oil and gas receipts, offset by $2,992
resulting from the decline in production during 2001 as compared to the same
period in 2000. The increase in production costs was primarily due to increased
production taxes associated with higher oil and gas prices. The increase in G&A
was primarily due to a higher percentage of the managing general partner's G&A
being allocated (limited to 3% of oil and gas revenues) as a result of increased
oil and gas revenues and an increase in the accrual for tax preparation fees.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities for the three months ended
March 31, 2001 and 2000 were related to expenditures for upgrades of oil and gas
equipment on active properties.

Proceeds from disposition of assets of $5,357 and $5,487 received during the
three months ended March 31, 2001 and 2000, respectively, were derived from the
sale of equipment on one fully depleted well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $773,504, of which $7,735 was distributed to the managing general partner
and $765,769 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $488,299, of which $4,883 was
distributed to the managing general partner and $483,416 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.


----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                                       9

   1503




                           Part II. Other Information


Item 6.     Exhibits and Reports on Form 8-K

(a)     Exhibits - none

(b)     Reports on Form 8-K - none.




                                        10

   1504


                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                          PARKER & PARSLEY 90-B, L.P.


                                 By:      Pioneer Natural Resources USA, Inc.
                                           Managing General Partner



Dated:  May 11, 2001             By:      /s/ Rich Dealy
                                          -----------------------------------
                                          Rich Dealy, Vice President
                                            and Chief Accounting Officer



                                       11



   1505
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-26097-07


                           PARKER & PARSLEY 90-B, L.P.
             (Exact name of Registrant as specified in its charter)


                                                                              
                     DELAWARE                                                                75-2329287
      --------------------------------------                                         --------------------------
      (State or other jurisdiction of                                                   (I.R.S. Employer
      incorporation or organization)                                                 Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                                 75039
----------------------------------------------------------------                               ----------
           (Address of principal executive offices)                                            (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
           Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$32,181,000.

     As of March 8, 2001, the number of outstanding limited partnership
interests was 32,264.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   1506

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 90-B, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 32,264 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA supplies all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 48% was attributable to sales made to
Plains Marketing, L.P., 10% to TEPPCO Crude Oil LLC and 10% to Phillips
Petroleum Company. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial


                                        2

   1507





liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 104
oil and gas wells. One well has been plugged and abandoned. At December 31,
2000, the Partnership had 103 producing oil and gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                        3

   1508
                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
            DISTRIBUTIONS

At March 8, 2001, the Partnership had 32,264 outstanding limited partnership
interests held of record by 2,201 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $2,237,802 and $736,663,
respectively, of such revenue-related distributions were made to the limited
partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                       2000             1999             1998            1997            1996
                                   ------------      -----------      ----------      -----------     -----------
                                                                                     
Operating results:
-----------------
  Oil and gas sales                $  4,103,548     $  2,461,819     $ 2,074,056     $  3,033,675    $  3,748,608
                                    ===========      ===========      ==========      ===========     ===========

  Impairment of oil and gas
    properties                     $     86,231     $    240,063     $   744,642     $    891,257    $     61,080
                                    ===========      ===========      ==========      ===========     ===========

  Net income (loss)                $  2,136,271     $    447,469     $(1,011,459)    $   (149,382)   $  1,479,052
                                    ===========      ===========      ==========      ===========     ===========

  Allocation of net income
   (loss):
    Managing general partner       $     21,363     $      4,475     $   (10,115)    $     (1,494)   $     14,790
                                    ===========      ===========      ==========      ===========     ===========

    Limited partners               $  2,114,908     $    442,994     $(1,001,344)    $   (147,888)   $  1,464,262
                                    ===========      ===========      ==========      ===========     ===========

  Limited partners' net income
    (loss) per limited partnership
    interest                       $      65.55     $      13.73     $    (31.04)    $      (4.58)   $      45.38
                                    ===========      ===========      ==========      ===========     ===========

  Limited partners' cash
    distributions per limited
    partnership interest           $      69.36     $      22.83     $     23.66     $      52.38    $      56.25
                                    ===========      ===========      ==========      ===========     ===========

At year end:
-----------
  Identifiable assets              $  5,144,391     $  5,292,769     $ 5,585,045     $  7,399,664    $  9,230,704
                                    ===========      ===========      ==========      ===========     ===========



                                        4

   1509



ITEM 7.    MANAGEMENT' DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
            RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 67% to $4,103,548 for 2000 as
compared to $2,461,819 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 99,252
barrels of oil, 45,552 barrels of natural gas liquids ("NGLs") and 175,696 mcf
of gas were sold, or 174,087 barrel of oil equivalents ("BOEs"). In 1999, 98,658
barrels of oil, 47,406 barrels of NGLs and 192,016 mcf of gas were sold, or
178,067 BOEs. Due to the decline characteristics of the Partnership's oil and
gas properties, management expects a certain amount of decline in production in
the future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.00, or 70%, from
$17.23 in 1999 to $29.23 in 2000. The average price received per barrel of NGLs
increased $5.96, or 63%, from $9.49 in 1999 to $15.45 in 2000. The average price
received per mcf of gas increased 75% from $1.62 in 1999 to $2.84 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gain on disposition of assets of $5,487 recognized in 2000 was due to equipment
credits received on one fully depleted well.

Total costs and expenses decreased in 2000 to $2,004,420 as compared to
$2,029,978 in 1999, a decrease of $25,558, or 1%. The decrease was due to
declines in the impairment of oil and gas properties and depletion, offset by
increases in production costs and general and administrative expenses ("G&A").

Production costs were $1,511,223 in 2000 and $1,296,822 in 1999, resulting in an
increase of $214,401, or 17%. The increase was primarily due to higher
production taxes associated with higher oil and gas prices and additional well
maintenance and workover costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
31% from $93,562 in 1999 to $122,731 in 2000 primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $109,474 in 2000 and $73,707 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

                                        5

   1510
In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized
non-cash charges of $86,231 and $240,063 related to its oil and gas properties
during 2000 and 1999, respectively.

Depletion was $284,235 in 2000 compared to $399,531 in 1999, representing a
decrease of $115,296, or 29%. This decrease was primarily due to an 81,075
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 19% to $2,461,819 from
$2,074,056 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 98,658 barrels of oil,
47,406 barrels of NGLs and 192,016 mcf of gas were sold, or 178,067 BOEs. In
1998, 111,585 barrels of oil, 47,190 barrels of NGLs and 199,215 mcf of gas were
sold, or 191,978 BOEs.

The average price received per barrel of oil increased $4.11, or 31%, from
$13.12 in 1998 to $17.23 in 1999. The average price received per barrel of NGLs
increased $2.89, or 44%, from $6.60 in 1998 to $9.49 in 1999. The average price
received per mcf of gas increased 8% from $1.50 in 1998 to $1.62 in 1999.

A gain on disposition of assets of $4,527 recognized during 1998 was due to
credits received from the disposal of oil and gas equipment on one fully
depleted well and one well that was plugged and abandoned in a prior year.

Total costs and expenses decreased in 1999 to $2,029,978 as compared to
$3,108,696 in 1998, a decrease of $1,078,718, or 35%. The decrease was due to
declines in the impairment of oil and gas properties, depletion and production
costs, offset by an increase in G&A.

Production costs were $1,296,822 in 1999 and $1,403,494 in 1998, resulting in a
$106,672 decrease, or 8%. The decrease was due to declines in well maintenance
costs, ad valorem taxes and workover costs.

During this period, G&A increased 29% from $72,284 in 1998 to $93,562 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $73,707 in
1999 and $62,152 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $240,063 and $744,642
related to its oil and gas properties during 1999 and 1998, respectively.


                                        6

   1511
Depletion was $399,531 in 1999 compared to $888,276 in 1998. This represented a
decrease of $488,745, or 55%. This decrease was primarily due to an increase in
proved reserves of 761,146 barrels of oil during 1999 due to higher commodity
prices, a reduction in the Partnership's net depletable basis from charges taken
in accordance with SFAS 121 during the fourth quarter of 1998 and a decline in
oil production of 12,927 barrels for the period ended December 31, 1999 compared
to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $1,473,163 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $1,657,757 and a decline in working capital of
$58,976, offset by increases in production costs paid of $214,401 and G&A
expenses paid of $29,169. The increase in oil and gas receipts resulted from the
increase in commodity prices during 2000 which contributed an additional
$1,715,313 to oil and gas receipts, offset by $57,556 resulting from the decline
in production during 2000. The increase in production costs was primarily due to
increased production taxes associated with higher oil and gas prices and
additional well maintenance and workover costs incurred to stimulate well
production. The increase in G&A was primarily due to higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active oil and gas properties.

Proceeds from disposition of assets of $5,487 recognized in 2000 were due to
equipment credits received on one fully depleted well.


                                        7

   1512
Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $2,260,406, of which $22,604
was distributed to the managing general partner and $2,237,802 to the limited
partners. In 1999, cash distributions to the partners were $744,104, of which
$7,441 was distributed to the managing general partner and $736,663 to the
limited partners.

















                                        8

   1513



ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                         Page
                                                                                         ----

                                                                                     
Financial Statements of Parker & Parsley 90-B, L.P.:
 Independent Auditors' Report.........................................................    10
 Balance Sheets as of December 31, 2000 and 1999......................................    11
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    12
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    13
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    14
 Notes to Financial Statements........................................................    15












                                        9

   1514
                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90-B, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90-B, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90-B, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       10

   1515
                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                   2000            1999
                                                               -----------      ----------
              ASSETS
              ------

                                                                         
Current assets:
  Cash                                                        $    364,895     $   311,017
  Accounts receivable - oil and gas sales                          568,283         441,577
                                                               -----------      ----------

        Total current assets                                       933,178         752,594
                                                               -----------      ----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                          26,110,930      26,069,426
Accumulated depletion                                          (21,899,717)    (21,529,251)
                                                               -----------      ----------

        Net oil and gas properties                               4,211,213       4,540,175
                                                               -----------      ----------

                                                              $  5,144,391     $ 5,292,769
                                                               ===========      ==========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                $     42,091     $    66,334

Partners' capital:
  Managing general partner                                          51,027          52,268
  Limited partners (32,264 interests)                            5,051,273       5,174,167
                                                               -----------      ----------

                                                                 5,102,300       5,226,435
                                                               -----------      ----------

                                                              $  5,144,391     $ 5,292,769
                                                               ===========      ==========









   The accompanying notes are an integral part of these financial statements.

                                       11

   1516



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                      2000          1999           1998
                                                   ----------    ----------     ----------

                                                                    
Revenues:
  Oil and gas                                     $ 4,103,548   $ 2,461,819    $ 2,074,056
  Interest                                             31,656        15,628         18,654
  Gain on disposition of assets                         5,487            -           4,527
                                                   ----------    ----------     ----------

                                                    4,140,691     2,477,447      2,097,237
                                                   ----------    ----------     ----------

Costs and expenses:
  Oil and gas production                            1,511,223     1,296,822      1,403,494
  General and administrative                          122,731        93,562         72,284
  Impairment of oil and gas properties                 86,231       240,063        744,642
  Depletion                                           284,235       399,531        888,276
                                                   ----------    ----------     ----------

                                                    2,004,420     2,029,978      3,108,696
                                                   ----------    ----------     ----------

Net income (loss)                                 $ 2,136,271   $   447,469    $(1,011,459)
                                                   ==========    ==========     ==========

Allocation of net income (loss):
  Managing general partner                        $    21,363    $    4,475    $   (10,115)
                                                    =========     ==========     ==========

  Limited partners                                $ 2,114,908   $   442,994    $(1,001,344)
                                                   ==========    ==========     ==========

Net income (loss) per limited
  partnership interest                            $     65.55    $    13.73    $    (31.04)
                                                   ==========    ==========     ==========



   The accompanying notes are an integral part of these financial statements.

                                       12

   1517



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                  Managing
                                                  general         Limited
                                                  partner         partners        Total
                                                 ---------       ----------     ----------


                                                                     
Partners' capital at January 1, 1998            $   73,061      $ 7,232,631    $ 7,305,692

   Distributions                                    (7,712)        (763,451)      (771,163)

   Net loss                                        (10,115)      (1,001,344)    (1,011,459)
                                                 ---------       ----------     ----------

Partners' capital at December 31, 1998              55,234        5,467,836      5,523,070

   Distributions                                    (7,441)        (736,663)      (744,104)

   Net income                                        4,475          442,994        447,469
                                                 ---------       ----------     ----------

Partners' capital at December 31, 1999              52,268        5,174,167      5,226,435

   Distributions                                   (22,604)      (2,237,802)    (2,260,406)

   Net income                                       21,363        2,114,908      2,136,271
                                                 ---------       ----------     ----------

Partners' capital at December 31, 2000          $   51,027      $ 5,051,273    $ 5,102,300
                                                 =========       ==========     ==========





   The accompanying notes are an integral part of these financial statements.


                                       13

   1518



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                      2000          1999           1998
                                                   ----------    ----------     -----------

                                                                     
Cash flows from operating activities:
  Net income (loss)                               $ 2,136,271   $   447,469    $ (1,011,459)
  Adjustments to reconcile net income (loss)
    to net cash provided by operating
    activities:
      Impairment of oil and gas properties             86,231       240,063         744,642
      Depletion                                       284,235       399,531         888,276
      Gain on disposition of assets                    (5,487)           -           (4,527)
  Changes in assets and liabilities:
      Accounts receivable                            (126,706)     (214,284)        116,516
      Accounts payable                                (24,243)        4,359         (31,997)
                                                   ----------    ----------     -----------

        Net cash provided by operating activities   2,350,301       877,138         701,451
                                                   ----------    ----------     -----------

Cash flows from investing activities:
  Additions to oil and gas properties                 (41,504)      (33,486)        (49,747)
  Proceeds from disposition of assets                   5,487            -            4,527
                                                   ----------    ----------     -----------

        Net cash used in investing activities         (36,017)      (33,486)        (45,220)
                                                   ----------    ----------     -----------

Cash flows used in financing activities:
  Cash distributions to partners                   (2,260,406)     (744,104)       (771,163)
                                                   ----------    ----------     -----------

Net increase (decrease) in cash                        53,878        99,548        (114,932)
Cash at beginning of year                             311,017       211,469         326,401
                                                   ----------    ----------     -----------

Cash at end of year                                $  364,895    $  311,017     $   211,469
                                                   ==========    ==========     ===========




   The accompanying notes are an integral part of these financial statements.

                                       14

   1519



                           PARKER & PARSLEY 90-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 90-B, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.


                                       15

   1520
      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $86,231, $240,063 and
$744,642 related to its proved oil and gas properties during 2000, 1999 and
1998, respectively.



                                       16

   1521
NOTE 4.    INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $632,807 greater than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:




                                                                  2000              1999             1998
                                                              ------------      ------------     -------------

                                                                                      
    Net income (loss) per statements of operations           $   2,136,271     $     447,469    $   (1,011,459)
    Depletion and depreciation provisions for tax
       reporting purposes less than amounts for
       financial reporting purposes                                246,057           359,438           475,607
    Impairment of oil and gas properties for financial
       reporting purposes                                           86,231           240,063           744,642
    Other, net                                                      (4,768)          (12,935)           11,120
                                                              ------------      ------------     -------------

          Net income per Federal income tax
            returns                                          $   2,463,791     $   1,034,035    $      219,910
                                                              ============      ============     =============


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000         1999           1998
                                                   ---------     ---------      ---------

                                                                      
      Development costs                            $  41,504     $  33,486      $  49,747
                                                    ========      ========       ========


        Capitalized oil and gas properties consist of the following:



                                                                 2000             1999
                                                             ------------     -------------
                                                                      
      Proved properties:
        Property acquisition costs                          $   1,002,057    $    1,002,057
        Completed wells and equipment                          25,108,873        25,067,369
                                                             ------------     -------------

                                                               26,110,930        26,069,426
      Accumulated depletion                                   (21,899,717)      (21,529,251)
                                                             ------------     -------------

              Net oil and gas properties                    $   4,211,213    $    4,540,175
                                                             ============     =============



NOTE 6.    RELATED PARTY TRANSACTIONS

      Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                      2000          1999           1998
                                                   ---------     ---------      ---------
                                                                     
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements               $  572,323    $  581,191     $  568,275
                                                   ---------     ---------      ---------

    Reimbursement of general and administrative
      expenses                                    $  109,474    $   73,707     $   62,152



                                       17

   1522



      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and P&P Employees 90-B Conv., L.P. ("EMPL"), Parker & Parsley 90-B Conv., L.P.
and the Partnership (the "Partnerships") are parties to the Program agreement.
EMPL is a limited partnership organized for the benefit of certain employees of
Pioneer USA. EMPL was merged with Pioneer USA on December 28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:



                                                             Pioneer USA(1)   Partnerships(2)
                                                             --------------   ---------------
                                                                         
  Revenues:
    Proceeds from disposition of depreciable and
     depletable properties
      First three years                                        14.141414%        85.858586%
      After first three years                                  19.191919%        80.808081%
    All other revenues
      First three years                                        14.141414%        85.858586%
      After first three years                                  19.191919%        80.808081%
  Costs and expenses:
    Lease acquisition costs, drilling and completion
      costs and all other costs                                 9.090909%        90.909091%
    Operating costs, reporting and legal expenses and
     general and administrative expenses
      First three years                                        14.141414%        85.858586%
      After first three years                                  19.191919%        80.808081%


    (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
          at the Partnership level and 83 limited partner interests owned by
          Pioneer USA.
    (2)   The allocation between the Partnership and Parker & Parsley 90-B
          Conv., L.P. is  73.05994% and 26.94006%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                                              Oil and NGLs         Gas
                                                                 (bbls)           (mcf)
                                                              ------------      ----------

                                                                        
    Net proved reserves at January 1, 1998                     2,481,201         2,344,959
    Revisions                                                 (1,210,571)         (517,240)
    Production                                                  (158,775)         (199,215)
                                                              ------------      ----------

    Net proved reserves at December 31, 1998                   1,111,855         1,628,504
    Revisions                                                  1,181,592         1,807,095
    Production                                                  (146,064)         (192,016)
                                                              ------------      ----------

    Net proved reserves at December 31, 1999                   2,147,383         3,243,583
    Revisions                                                     46,430          (419,625)
    Production                                                  (144,804)         (175,696)
                                                              ------------      ----------

    Net proved reserves at December 31, 2000                   2,049,009         2,648,262
                                                              ============      ==========




                                       18

   1523




      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.19 per barrel of NGLs and $7.66 per mcf of gas,
discounted at 10% was approximately $15,617,000 and undiscounted was
$31,632,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider probable reserves, anticipated
future oil and gas prices, interest rates, changes in development and production
costs and risks associated with future production. Because of these and other
considerations, any estimate of fair value is necessarily subjective and
imprecise.



                                                          For the years ended December 31,
                                                       -------------------------------------
                                                          2000          1999         1998
                                                       ----------    ----------   ----------
                                                                   (in thousands)
                                                                       
Oil and gas producing activities:
  Future cash inflows                                 $    65,926   $    52,962  $    12,063
  Future production costs                                 (34,294)      (29,776)      (9,053)
                                                       ----------    ----------   ----------

                                                           31,632        23,186        3,010
  10% annual discount factor                              (16,015)      (11,296)      (1,016)
                                                       ----------    ----------   ----------

  Standardized measure of discounted future net
    cash flows                                        $    15,617   $    11,890  $     1,994
                                                       ==========    ==========   ==========





                                                          For the years ended December 31,
                                                      --------------------------------------
                                                          2000          1999         1998
                                                      -----------   -----------   ----------
                                                                   (in thousands)
                                                                        
  Oil and Gas Producing Activities:
    Oil and gas sales, net of production costs        $    (2,592)  $    (1,165)  $     (671)
    Net changes in prices and production costs              5,824         5,796       (6,480)
    Revisions of previous quantity estimates                 (153)        8,478       (1,405)
    Accretion of discount                                   1,189           199          982
    Changes in production rates, timing and other            (541)       (3,412)        (254)
                                                       ----------    ----------    ---------

    Change in present value of future net revenues          3,727         9,896       (7,828)
                                                       ----------    ----------    ---------

    Balance, beginning of year                             11,890         1,994        9,822
                                                       ----------    ----------    ---------

    Balance, end of year                               $   15,617   $    11,890   $    1,994
                                                       ==========    ==========    =========



                                       19

   1524




NOTE 8.    MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                       
              Plains Marketing, L.P.                 48%            46%            -
              TEPPCO Crude Oil LLC                   10%            11%            -
              Genesis Crude Oil, L.P.                 -              -            58%
              Western Gas Resources, Inc.             4%             5%           22%
              Phillips Petroleum Company             10%             5%            5%


      At December 31, 2000, the amounts receivable from Plains Marketing, L.P.,
TEPPCO Crude Oil LLC and Phillips Petroleum Company were $177,462, $37,001 and
$20,032, respectively, which are included in the caption "Accounts receivable -
oil and gas sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.



NOTE 9.    PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The




                                       20

   1525

      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the Partnership agreement, the managing general partner pays 1% of
      the Partnership's acquisition, drilling and completion costs and 1% of its
      operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of
      $32,264,000. The managing general partner is required to contribute
      amounts equal to 1% of initial Partnership capital less commission and
      organization and offering costs allocated to the limited partners and to
      contribute amounts necessary to pay costs and expenses allocated to it
      under the Partnership agreement to the extent its share of revenues does
      not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
            AND FINANCIAL DISCLOSURE

None.





                                       21

   1526



                                    PART III

ITEM 10.   DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                      Age at
                                    December 31,
       Name                            2000                       Position
       ----                            ----                       --------

                                                
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


       Scott D. Sheffield.  Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.


                                       22

   1527



      Timothy L. Dove.  Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone.  Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

      Mark L. Withrow.  Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy.  Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.


                                       23

   1528
ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 15% during the first three years
and approximately 20% after three years of its operating and general and
administrative expenses. In return, they are allocated approximately 15% during
the first three years and approximately 20% after three years of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 83 limited partnership interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                       24

   1529





                                                     2000           1999          1998
                                                   --------      ---------      --------
                                                                     
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements               $ 572,323      $ 581,191     $ 568,275

    Reimbursement of general and administrative
      expenses                                    $ 109,474      $  73,707     $  62,152


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.


                                       25

   1530



                                     PART IV

ITEM 14.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                 Statements of partners' capital for the years ended December
                   31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                 Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.


                                       26

   1531



                               S I G N A T U R E S


      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.


                                          PARKER & PARSLEY 90-B, L.P.

Dated: March 28, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                ------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                     
/s/ Scott D. Sheffield               President of Pioneer USA                March 28, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                  Executive Vice President, Chief         March 28, 2001
-------------------------------      Financial Officer and Director of
Timothy L. Dove                      Pioneer USA


/s/ Dennis E. Fagerstone             Executive Vice President and            March 28, 2001
-------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                  Executive Vice President, General       March 28, 2001
-------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                     Executive Vice President - Domestic     March 28, 2001
-------------------------------      Operations and Director of Pioneer
Danny Kellum                         USA


/s/ Rich Dealy                       Vice President and Chief Accounting     March 28, 2001
-------------------------------      Officer of Pioneer USA
Rich Dealy



                                       27

   1532


                           PARKER & PARSLEY 90-B, L.P.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                             Description                              Page
-----------                             -----------                              ----

                                                                          
   3(a)                 Form of Agreement of Limited Partnership                   -
                        of Parker & Parsley 90-B, L.P. incorporated
                        by reference to Exhibit A of the Post-Effective
                        Amendment No. 1 of the Partnership's
                        Registration Statement on Form S-1
                        (Registration No. 33-26097)

   4(b)                 Form of Limited Partner Subscription Agreement             -
                        incorporated by reference to Exhibit C of the
                        Post-Effective Amendment No. 1 of the
                        Partnership's Registration Statement on Form
                        S-1 (Registration No. 33-26097)

   4(b)                 Form of General Partner Subscription Agreement             -
                        incorporated by reference to Exhibit D of the
                        Post-Effective Amendment No. 1 of the
                        Partnership's Registration Statement on Form
                        S-1 (Registration No. 33-26097)

   4(b)                 Power of Attorney incorporated by reference to             -
                        Exhibit B of Amendment No. 1 of the
                        Partnership's Registration Statement on Form
                        S-1 (Registration No. 33-26097)

   4(c)                 Specimen Certificate of Limited Partnership                -
                        Interest incorporated by reference to Exhibit 4c
                        of the Partnership's Registration Statement on
                        Form S-1 (Registration No. 33-26097)

  10(b)                 Form of Development Drilling Program                       -
                        Agreement incorporated by reference to Exhibit
                        B of the Post-Effective Amendment No. 1 of
                        the Partnership's Registration Statement on
                        Form S-1 (Registration No. 33-26097)




                                       28
   1533



                           PARKER & PARSLEY 90-B, L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                           Years ended December 31,
                                   ---------------------   ---------------------------------------------------------------
                                     2001        2000         2000         1999          1998         1997         1996
                                   --------   ----------   ----------   ----------   -----------   ----------   ----------
                                                                                           
Operating results:
  Oil and gas sales                $          $  896,935   $4,103,548   $2,461,819   $ 2,074,056   $3,033,675   $3,748,608
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

  Impairment of oil and gas
    properties                     $          $       --   $   86,231   $  240,063   $   744,642   $  891,257   $   61,080
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

  Net income (loss)                $          $  445,716   $2,136,271   $  447,469   $(1,011,459)  $ (149,382)  $1,479,052
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
        partner                    $          $    4,457   $   21,363   $    4,475   $   (10,115)  $   (1,494)  $   14,790
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

      Limited partners             $          $  441,259   $2,114,908   $  442,994   $(1,001,344)  $ (147,888)  $1,464,262
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

  Limited partners' net
    income (loss) per
    limited partnership
    interest                       $          $    13.68   $    65.55   $    13.73   $    (31.04)  $    (4.58)  $    45.38
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    14.98   $    69.36   $    22.83   $     23.66   $    52.38   $    56.25
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========

At year end:
  Identifiable assets              $          $5,258,178   $5,144,391   $5,292,769   $ 5,585,045   $7,399,664   $9,230,704
                                   ========   ==========   ==========   ==========   ===========   ==========   ==========




   1534
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

        PARKER & PARSLEY 90-C CONV., L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED         , 2001

                                   ---------

                 THE DATE OF THIS SUPPLEMENT IS         , 2001

                                   ---------


     This document contains important information specific to Parker & Parsley
90-C Conv., L.P., and supplements the proxy statement/prospectus dated      ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 90-C Conv., L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                      -1-
   1535
                        PARKER & PARSLEY 90-C CONV., L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                         
Aggregate Initial Investment by the Limited Partners(a)                                     $ 7,531

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                 $ 4,950

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding           $ 1,830
Pioneer USA(a),(b)

Merger Value per $1,000 Limited Partner Investment(b),(c)                                   $243.96

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for          3.32 times
the past four quarterly distributions including the distribution in July 2001(b),(c)

Book Value per $1,000 Limited Partner Investment:

          --   as of March 31, 2001(c)                                                      $126.73

          --   as of December 31, 2000(c)                                                   $132.75

Going Concern Value per $1,000 Limited Partner Investment(c),(d)                            $226.16

Liquidation Value per $1,000 Limited Partner Investment(c),(e)                              $236.76

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment       $   149
(c),(f)


---------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                 INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2040, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   1536

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-26097-10


                        PARKER & PARSLEY 90-C CONV., L.P.
             (Exact name of Registrant as specified in its charter)

                         Delaware                          75-2347264
            ----------------------------------       ---------------------
             (State or other jurisdiction of            (I.R.S. Employer
             incorporation or organization)          Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas      75039
----------------------------------------------------------------    ----------
            (Address of principal executive offices)                (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]







   1537



                        PARKER & PARSLEY 90-C CONV., L.P.

                                TABLE OF CONTENTS




                                                                        Page
                                                                     
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................    9

            Signatures...............................................   10



                                        2

   1538



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS


                                                            March 31,          December 31,
                                                              2001                 2000
                                                          ------------         ------------
                                                           (Unaudited)
                 ASSETS

                                                                         
Current assets:
   Cash                                                   $     94,712         $    106,593
   Accounts receivable - oil and gas sales                     108,558              119,396
                                                          ------------         ------------
         Total current assets                                  203,270              225,989
                                                          ------------         ------------
Oil and gas properties - at cost, based on the
   successful efforts accounting method                      5,800,209            5,798,493
Accumulated depletion                                       (5,014,101)          (5,000,618)
                                                          ------------         ------------
         Net oil and gas properties                            786,108              797,875
                                                          ------------         ------------
                                                          $    989,378         $  1,023,864
                                                          ============         ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
   Accounts payable:
     Affiliate                                            $     17,547         $     14,074
     Other                                                       7,812                   --
                                                          ------------         ------------
                                                                25,359               14,074
                                                          ------------         ------------
Partners' capital:
   Managing general partner                                      9,609               10,067
   Limited partners (7,531 interests)                          954,410              999,723
                                                          ------------         ------------
                                                               964,019            1,009,790
                                                          ------------         ------------
                                                          $    989,378         $  1,023,864
                                                          ============         ============



  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.


                                        3

   1539



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                                 Three months ended
                                                                      March 31,
                                                          --------------------------------
                                                              2001                2000
                                                          ------------        ------------
                                                                        
Revenues:
  Oil and gas                                             $    230,925        $    193,711
  Interest                                                       1,788               1,497
                                                          ------------        ------------
                                                               232,713             195,208
                                                          ------------        ------------
Costs and expenses:
  Oil and gas production                                        95,640              83,711
  General and administrative                                     8,175               5,934
  Depletion                                                     13,483              13,742
                                                          ------------        ------------
                                                               117,298             103,387
                                                          ------------        ------------
Net income                                                $    115,415        $     91,821
                                                          ============        ============
Allocation of net income:
  Managing general partner                                $      1,154        $        918
                                                          ============        ============
  Limited partners                                        $    114,261        $     90,903
                                                          ============        ============
Net income per limited partnership interest               $      15.17        $      12.07
                                                          ============        ============


         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        4

   1540



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                                        Managing
                                        general             Limited
                                        partner             partners             Total
                                      -----------         -----------         -----------
                                                                     
Balance at January 1, 2001            $    10,067         $   999,723         $ 1,009,790

    Distributions                          (1,612)           (159,574)           (161,186)

    Net income                              1,154             114,261             115,415
                                      -----------         -----------         -----------

Balance at March 31, 2001             $     9,609         $   954,410         $   964,019
                                      ===========         ===========         ===========


         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        5

   1541



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                                  Three months ended
                                                                      March 31,
                                                          ---------------------------------
                                                              2001                 2000
                                                          ------------         ------------
                                                                         
Cash flows from operating activities:
   Net income                                             $    115,415         $     91,821
   Adjustments to reconcile net income to net
     cash provided by operating activities:
       Depletion                                                13,483               13,742
   Changes in assets and liabilities:
       Accounts receivable                                      10,838                3,534
       Accounts payable                                         11,285                2,095
                                                          ------------         ------------
         Net cash provided by operating activities             151,021              111,192
                                                          ------------         ------------
Cash flows used in investing activities:
   Additions to oil and gas properties                          (1,716)              (6,883)

Cash flows used in financing activities:
   Cash distributions to partners                             (161,186)            (103,576)
                                                          ------------         ------------
Net increase (decrease) in cash                                (11,881)                 733
Cash at beginning of period                                    106,593              107,295
                                                          ------------         ------------
Cash at end of period                                     $     94,712         $    108,028
                                                          ============         ============


         The financial information included herein has been prepared by
the managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.


                                        6

   1542



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 90-C Conv., L.P. (the "Partnership") was organized as a general
partnership  in 1990 under the laws of the State of Texas and was converted to a
Delaware limited partnership on August 1, 1991.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 19% to $230,925 for the three
months ended March 31, 2001 as compared to $193,711 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 5,811
barrels of oil, 859 barrels of natural gas liquids ("NGLs") and 8,151 mcf of gas
were sold, or 8,029 barrel of oil equivalents ("BOEs"). For the three months
ended March 31, 2000, 5,802 barrels of oil, 1,943 barrels of NGLs and 6,434 mcf
of gas were sold, or 8,817 BOEs.

                                        7

   1543




The average price received per barrel of oil increased $.92, or 3%, from $27.16
for the three months ended March 31, 2000 to $28.08 for the same period in 2001.
The average price received per barrel of NGLs increased $6.00, or 46%, from
$12.95 for the three months ended March 31, 2000 to $18.95 for the same period
in 2001. The average price received per mcf of gas increased 270% from $1.71
during the three months ended March 31, 2000 to $6.33 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $117,298 for the three months ended March
31, 2001 as compared to $103,387 for the same period in 2000, an increase of
$13,911, or 13%. This increase was primarily due increases in production costs
and general and administrative expenses ("G&A"), offset by a decline in
depletion.

Production costs were $95,640 for the three months ended March 31, 2001 and
$83,711 for the same period in 2000, resulting in an increase of $11,929, or
14%. The increase was primarily due to additional well maintenance costs
incurred to stimulate well production and higher production taxes associated
with higher oil and gas revenues.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 38% from $5,934 for the three months ended March 31, 2000 to $8,175
for the same period in 2001 primarily due to a higher percentage of the managing
general partner's G&A being allocated (limited to 3% of oil and gas revenues) as
a result of increased oil and gas revenues and an increase in the accrual for
tax preparation fees.

Depletion was $13,483 for the three months ended March 31, 2001 as compared to
$13,742 for the same period in 2000, a decrease of $259, or 2%. This decrease
was primarily due to positive revisions to proved reserves on one well during
the three months ended March 31, 2001.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $39,829 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $37,505 in oil and gas sales receipts
and a reduction in working capital of $16,494, offset by increases in production
costs of $11,929 and G&A expenses of $2,241. The increase in oil and gas
receipts resulted from the increase in commodity prices during 2001 which
contributed an additional $46,902 to oil and gas receipts, offset by $9,397
resulting from the decline in production during 2001 as compared to the same
period in 2000. The increase in production costs was primarily due to additional
well maintenance costs incurred to stimulate well production and increased
production taxes associated with higher oil and gas prices. The increase in G&A


                                        8

   1544



was primarily due to a higher percentage of the managing general partner's G&A
being allocated (limited to 3% of oil and gas revenues) as a result of increased
oil and gas revenues and an increase in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 related to expenditures for upgrades of oil and gas
equipment on active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $161,186, of which $1,612 was distributed to the managing general partner
and $159,574 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $103,576, of which $1,036 was
distributed to the managing general partner and $102,540 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

(a)      Exhibits - none

(b)      Reports on Form 8-K - none.

                                        9

   1545


                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                          PARKER & PARSLEY 90-C CONV., L.P.


                                 By:      Pioneer Natural Resources USA, Inc.
                                           Managing General Partner



Dated:  May 11, 2001             By:      /s/ Rich Dealy
                                          -----------------------------------
                                          Rich Dealy, Vice President
                                            and Chief Accounting Officer



                                       10

   1546
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-26097-10


                        PARKER & PARSLEY 90-C CONV., L.P.
             (Exact name of Registrant as specified in its charter)


                                                                            
                 DELAWARE                                                                  75-2347264
     -------------------------------                                               --------------------------
     (State or other jurisdiction of                                                  (I.R.S. Employer
     incorporation or organization)                                                Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                              75039
----------------------------------------------------------------                          -------------
          (Address of principal executive offices)                                          (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
                   Securities registered pursuant to Section
                               12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                 -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$7,501,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 7,531.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.


   1547

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 90-C Conv., L.P. (the "Partnership") is a general partnership
organized in 1990 under the laws of the State of Texas. The Partnership
converted to a Delaware limited partnership on August 1, 1991. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 7,531 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 64% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial

                                        2

   1548
liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 44
oil and gas wells. One well was sold and one well was plugged and abandoned due
to uneconomical operations. At December 31, 2000, the Partnership had 42
producing oil and gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.



                                        3

   1549



                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
            DISTRIBUTIONS

At March 8, 2001, the Partnership had 7,531 outstanding limited partnership
interests held of record by 505 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $492,300 and $135,825, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                        2000             1999             1998            1997            1996
                                    -----------      -----------      -----------     -----------     -----------
                                                                                     
Operating results:
-----------------
  Oil and gas sales                $    917,184     $    537,893     $    430,499    $    661,475    $    837,849
                                    ===========      ===========      ===========     ===========     ===========

  Impairment of oil and gas
     properties                    $         -      $         -      $    185,784    $     79,288    $         -
                                    ===========      ===========      ===========     ===========     ===========

  Net income (loss)                $    509,518     $    137,106     $   (258,625)   $    105,740    $    359,349
                                    ===========      ===========      ===========     ===========     ===========

  Allocation of net income
    (loss):
     Managing general partner      $      5,095     $      1,371     $     (2,586)   $      1,057    $      3,593
                                    ===========      ===========      ===========     ===========     ===========

     Limited partners              $    504,423     $    135,735     $   (256,039)   $    104,683    $    355,756
                                    ===========      ===========      ===========     ===========     ===========

  Limited partners' net income
     (loss) per limited
     partnership interest          $      66.98     $      18.02     $     (34.00)   $      13.90    $      47.24
                                    ===========      ===========      ===========     ===========     ===========

  Limited partners' cash
     distributions per limited
     partnership interest          $      65.37     $      18.04     $      17.30    $      47.53    $      51.98
                                    ===========      ===========      ===========     ===========     ===========

At year end:
-----------
  Identifiable assets              $  1,023,864     $  1,014,263     $  1,011,034    $  1,411,804    $  1,661,127
                                    ===========      ===========      ===========     ===========     ===========




                                        4

   1550



ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
            RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 71% to $917,184 for 2000 as
compared to $537,893 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 23,602 barrels
of oil, 9,171 barrels of natural gas liquids ("NGLs") and 30,423 mcf of gas were
sold, or 37,844 barrel of oil equivalents ("BOEs"). In 1999, 23,568 barrels of
oil, 9,050 barrels of NGLs and 29,399 mcf of gas were sold, or 37,518 BOEs. Due
to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.21, or 71%, from
$17.13 in 1999 to $29.34 in 2000. The average price received per barrel of NGLs
increased $5.60, or 60%, from $9.31 in 1999 to $14.91 in 2000. The average price
received per mcf of gas increased 70% from $1.70 in 1999 to $2.89 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than received in 2000.

Gains on dispositions of assets of $388 and $104 recognized during 2000 and
1999, respectively, were due to equipment credits received on a fully depleted
well in each year.

Total costs and expenses increased in 2000 to $416,488 compared to $405,150 in
1999, an increase of $11,338, or 3%. This increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $334,055 in 2000 and $297,353 in 1999, resulting in an
increase of $36,702, or 12%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period G&A increased
45% from $20,987 in 1999 to $30,429 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $27,439 in 2000 and $16,060 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.



                                        5

   1551
Depletion was $52,004 in 2000 as compared to $86,810 in 1999, representing a
decrease of $34,806, or 40%. This decrease was primarily due to a 31,374 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 25% to $537,893 from
$430,499 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 23,568 barrels of oil,
9,050 barrels of NGLs and 29,399 mcf of gas were sold, or 37,518 BOEs. In 1998,
24,493 barrels of oil, 8,694 barrels of NGLs and 30,348 mcf of gas were sold, or
38,245 BOEs.

The average price received per barrel of oil increased $3.89, or 29%, from
$13.24 in 1998 to $17.13 in 1999. The average price received per barrel of NGLs
increased $2.51, or 37%, from $6.80 in 1998 to $9.31 in 1999. The average price
received per mcf of gas increased 10% from $1.55 in 1998 to $1.70 in 1999.

Total costs and expenses decreased in 1999 to $405,150 compared to $693,871 in
1998, a decrease of $288,721, or 42%. This decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $297,353 in 1999 and $314,363 in 1998, resulting in a
decrease of $17,010, or 5%. The decrease was due to declines in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes.

During this period G&A increased 39% from $15,084 in 1998 to $20,987 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $16,060 in
1999 and $12,838 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $185,784 related to its oil and gas properties during 1998.

Depletion was $86,810 in 1999 compared to $178,640 in 1998. This represented a
decrease of $91,830, or 51%. This decrease was primarily the result of an
increase in proved reserves of 207,077 barrels of oil during 1999 as a result of
higher commodity prices and a reduction in the Partnership's net depletable
basis from charges taken in accordance with SFAS 121 during the fourth quarter
of 1998.





                                        6

   1552
Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $330,268 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $383,466, offset by increases in production costs paid
of $36,702, G&A expenses paid of $9,442 and working capital of $7,054. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $377,706 to oil and gas receipts and
$5,760 resulting from the increase in production during 2000. The increase in
production costs was primarily due to increased production taxes associated with
higher oil and gas prices and well maintenance costs incurred to stimulate well
production. The increase in G&A was primarily due to higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active oil and gas properties.

Proceeds from dispositions of assets of $388 and $104 recognized during 2000 and
1999, respectively, were related to equipment credits received on a fully
depleted well in each year.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $497,273, of which $4,973 was
distributed to the managing general partner and $492,300 to the limited
partners. In 1999, cash distributions to the partners were $137,197, of which
$1,372 was distributed to the managing general partner and $135,825 to the
limited partners.



                                        7

   1553



ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                            Page
                                                                            ----

                                                                        
Financial Statements of Parker & Parsley 90-C Conv., L.P:
  Independent Auditors' Report..........................................      9
  Balance Sheets as of December 31, 2000 and 1999.......................     10
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998.................................................     11
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998....................................     12
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998.................................................     13
  Notes to Financial Statements.........................................     14




                                        8

   1554




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90-C Conv., L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90-C Conv., L.P. as of
December 31, 2000 and 1999, and the related statements of operations, partners'
capital and cash flows for each of the three years in the period ended December
31, 2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90-C Conv.,
L.P. as of December 31, 2000 and 1999, and the results of its operations and its
cash flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                               Ernst & Young LLP

Dallas, Texas
March 9, 2001


                                        9

   1555



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                                  2000                1999
                                                                             -------------       ------------
                 ASSETS
                 ------

                                                                                         
Current assets:
  Cash                                                                      $      106,593      $     107,295
  Accounts receivable - oil and gas sales                                          119,396             79,853
                                                                             -------------       ------------

         Total current assets                                                      225,989            187,148
                                                                             -------------       ------------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                           5,798,493          5,775,729
Accumulated depletion                                                           (5,000,618)        (4,948,614)
                                                                             -------------       ------------

         Net oil and gas properties                                                797,875            827,115
                                                                             -------------       ------------

                                                                            $    1,023,864      $   1,014,263
                                                                             =============       ============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                              $       14,074      $      16,718

Partners' capital:
  Managing general partner                                                          10,067              9,945
  Limited partners (7,531 interests)                                               999,723            987,600
                                                                             -------------       ------------

                                                                                 1,009,790            997,545
                                                                             -------------       ------------

                                                                            $    1,023,864      $   1,014,263
                                                                             =============       ============










   The accompanying notes are an integral part of these financial statements.

                                       10

   1556



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31







                                                                  2000              1999             1998
                                                              -----------       -----------      -----------

                                                                                       
Revenues:
   Oil and gas                                                $   917,184       $   537,893      $   430,499
   Interest                                                         8,434             4,259            4,747
   Gain on disposition of assets                                      388               104              -
                                                               ----------        ----------       ----------

                                                                  926,006           542,256          435,246
                                                               ----------        ----------       ----------

Costs and expenses:
   Oil and gas production                                         334,055           297,353          314,363
   General and administrative                                      30,429            20,987           15,084
   Impairment of oil and gas properties                               -                 -            185,784
   Depletion                                                       52,004            86,810          178,640
                                                               ----------        ----------       ----------

                                                                  416,488           405,150          693,871
                                                               ----------        ----------       ----------

Net income (loss)                                             $   509,518       $   137,106      $  (258,625)
                                                               ==========        ==========       ==========

Allocation of net income (loss):
   Managing general partner                                   $     5,095       $     1,371      $    (2,586)
                                                               ==========        ==========       ==========

   Limited partners                                           $   504,423       $   135,735      $  (256,039)
                                                               ==========        ==========       ==========

Net income (loss) per limited partnership interest            $     66.98       $     18.02      $    (34.00)
                                                               ==========        ==========       ==========













   The accompanying notes are an integral part of these financial statements.

                                       11

   1557



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                                Managing
                                                                general          Limited
                                                                partner          partners            Total
                                                             -------------    -------------     -------------


                                                                                      
Partners' capital at January 1, 1998                          $     13,848    $   1,374,010     $   1,387,858

    Distributions                                                   (1,316)        (130,281)         (131,597)

    Net loss                                                        (2,586)        (256,039)         (258,625)
                                                               -----------     ------------      ------------

Partners' capital at December 31, 1998                               9,946          987,690           997,636

    Distributions                                                   (1,372)        (135,825)         (137,197)

    Net income                                                       1,371          135,735           137,106
                                                               -----------     ------------      ------------

Partners' capital at December 31, 1999                               9,945          987,600           997,545

    Distributions                                                   (4,973)        (492,300)         (497,273)

    Net income                                                       5,095          504,423           509,518
                                                               -----------     ------------      ------------

Partners' capital at December 31, 2000                        $     10,067    $     999,723     $   1,009,790
                                                               ===========     ============      ============













   The accompanying notes are an integral part of these financial statements.

                                       12

   1558



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                                 2000              1999              1998
                                                             ------------     -------------     -------------
                                                                                      
Cash flows from operating activities:
 Net income (loss)                                           $    509,518     $     137,106     $    (258,625)
 Adjustments to reconcile net income (loss)
    to net cash provided by operating
    activities:
      Impairment of oil and gas properties                             -                 -            185,784
      Depletion                                                    52,004            86,810           178,640
      Gain on disposition of assets                                  (388)             (104)               -
 Changes in assets and liabilities:
      Accounts receivable                                         (39,543)          (38,453)           28,491
      Accounts payable                                             (2,644)            3,320           (10,548)
                                                              -----------      ------------      ------------

         Net cash provided by operating
           activities                                             518,947           188,679           123,742
                                                              -----------      ------------      ------------

Cash flows from investing activities:
 Additions to oil and gas properties                              (22,764)          (10,512)          (13,347)
 Proceeds from disposition of assets                                  388               104                -
                                                              -----------      ------------      ------------

         Net cash used in investing activities                    (22,376)          (10,408)          (13,347)
                                                              -----------      ------------      ------------

Cash flows used in financing activities:
 Cash distributions to partners                                  (497,273)         (137,197)         (131,597)
                                                              -----------      ------------      ------------

Net increase (decrease) in cash                                      (702)           41,074           (21,202)
Cash at beginning of year                                         107,295            66,221            87,423
                                                              -----------      ------------      ------------

Cash at end of year                                          $    106,593     $     107,295     $      66,221
                                                              ===========      ============      ============









   The accompanying notes are an integral part of these financial statements.

                                       13

   1559



                        PARKER & PARSLEY 90-C CONV., L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

       Parker & Parsley 90-C Conv., L.P. (the "Partnership") is a general
partnership organized in 1990 under the laws of the State of Texas. The
Partnership converted to a Delaware limited partnership on August 1, 1991. The
Partnership's managing general partner is Pioneer Natural Resources USA, Inc.
("Pioneer USA").

         The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

         A summary of the significant accounting policies consistently applied
in the preparation of the accompanying financial statements follows:

         Oil and gas properties - The Partnership utilizes the successful
efforts method of accounting for its oil and gas properties and equipment. Under
this method, all costs associated with productive wells and nonproductive
development wells are capitalized while nonproductive exploration costs are
expensed. Capitalized costs relating to proved properties are depleted using the
unit-of- production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

         Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

         Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

         Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

         Income taxes - A Federal income tax provision has not been included in
the financial statements as the income (loss) of the Partnership is included in
the individual Federal income tax returns of the respective partners.


                                       14

   1560


         Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

         General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

       Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

       Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

       Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

       In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $185,784 related to
its proved oil and gas properties during 1998.


                                       15

   1561




NOTE 4.    INCOME TAXES

       The financial statement basis of the Partnership's net assets and
liabilities was $49,618 less than the tax basis at December 31, 2000.

       The following is a reconciliation of net income (loss) per statements of
operations with the net income (loss) per Federal income tax returns for the
years ended December 31:




                                                             2000                  1999                 1998
                                                       --------------        ---------------       -------------

                                                                                         
     Net income (loss) per statements of operations    $      509,518        $       137,106       $    (258,625)
     Depletion and depreciation provisions for tax
       reporting purposes less than amounts for
       financial reporting purposes                            40,369                 76,676              50,997
     Impairment of oil and gas properties
       for financial reporting purposes                           -                      -               185,784
     Intangible development costs capitalized for
       financial reporting purposes and expensed for
       tax reporting purposes                                    (385)                   -                   -
     Other, net                                                (1,143)                (1,786)              1,870
                                                        -------------         --------------        ------------

          Net income (loss) per Federal
            income tax returns                         $      548,359        $       211,996       $     (19,974)
                                                        =============         ==============        ============



NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

       The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                 2000              1999              1998
                                                            -------------     ------------      ------------

                                                                                       
       Development costs                                    $      22,764     $     10,512      $     13,347
                                                             ============      ===========       ===========


            Capitalized oil and gas properties consist of the following:



                                                                               2000                   1999
                                                                           ------------          ------------
                                                                                          
     Proved properties:
        Property acquisition costs                                         $    226,701          $    226,701
        Completed wells and equipment                                         5,571,792             5,549,028
                                                                            -----------           -----------

                                                                              5,798,493             5,775,729
     Accumulated depletion                                                   (5,000,618)           (4,948,614)
                                                                            -----------           -----------

            Net oil and gas properties                                     $    797,875          $    827,115
                                                                            ===========           ===========



NOTE 6.    RELATED PARTY TRANSACTIONS

       Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                       16

   1562




                                                                   2000             1999              1998
                                                              --------------   --------------    --------------
                                                                                       
       Payment of lease operating and supervision
          charges in accordance with standard
          industry operating agreements                       $   130,806      $   126,701       $   124,074

       Reimbursement of general and administrative
          expenses                                            $    27,439      $    16,060       $    12,838


       The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 90-C Conv., L.P. ("EMPL"), Parker & Parsley 90-C, L.P. and the
Partnership (the "Partnerships") are parties to the Program agreement. EMPL is a
limited partnership organized for the benefit of certain employees of Pioneer
USA. EMPL was merged with Pioneer USA on December 28, 2000.

       The costs and revenues of the Program are allocated to Pioneer USA and
the Partnerships as follows:



                                                                           Pioneer USA (1)      Partnerships (2)
                                                                           ---------------      ----------------
                                                                                           
     Revenues:
       Proceeds from disposition of depreciable and depletable
         properties -
         First three years                                                    14.141414%           85.858586%
         After first three years                                              19.191919%           80.808081%
       All other revenues -
         First three years                                                    14.141414%           85.858586%
         After first three years                                              19.191919%           80.808081%
     Costs and expenses:
       Lease acquisition costs, drilling and completion costs
         and all other costs                                                   9.090909%           90.909091%
       Operating costs, reporting and legal expenses and
         general and administrative expenses -
         First three years                                                    14.141414%           85.858586%
         After first three years                                              19.191919%           80.808081%


    (1)   Excludes Pioneer USA's 1% general partner ownership which is allocated
          at the Partnership level and 30 limited partner interests owned by
          Pioneer USA.
    (2)   The allocation between the Partnership and Parker & Parsley 90-C, L.P.
          is 38.349119% and 61.650881%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

       The following table represents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.

                                       17

   1563






                                                                              Oil and NGLs             Gas
                                                                                 (bbls)               (mcf)
                                                                              ------------          ----------

                                                                                            
    Net proved reserves at January 1, 1998                                       424,601               426,720
    Revisions                                                                   (204,124)             (171,338)
    Production                                                                   (33,187)              (30,348)
                                                                              ----------            ----------

    Net proved reserves at December 31, 1998                                     187,290               225,034
    Revisions                                                                    293,912               357,964
    Production                                                                   (32,618)              (29,399)
                                                                              ----------            ----------

    Net proved reserves at December 31, 1999                                     448,584               553,599
    Revisions                                                                     50,848               (55,441)
    Production                                                                   (32,773)              (30,423)
                                                                              ----------            ----------

    Net proved reserves at December 31, 2000                                     466,659               467,735
                                                                              ==========            ==========


       As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.22 per barrel of NGLs and $7.80 per mcf of gas,
discounted at 10% was approximately $3,245,000 and undiscounted was $6,366,000.

       Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

      The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

      Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.






                                                                          For the years ended December 31,
                                                                   ---------------------------------------------
                                                                       2000             1999            1998
                                                                   ------------     ------------    ------------
                                                                                   (in thousands)
                                                                                          
Oil and gas producing activities:
   Future cash inflows                                             $     14,206     $     11,167    $      2,041
   Future production costs                                               (7,840)          (6,472)         (1,624)
                                                                   ------------     ------------    ------------

                                                                          6,366            4,695             417
   10% annual discount factor                                            (3,121)          (2,211)           (116)
                                                                   ------------     ------------    ------------

   Standardized measure of discounted future net cash flows        $      3,245     $      2,484    $        301
                                                                   ============     ============    ============






                                       18

   1564



                                                                           For the years ended December 31,
                                                                   ---------------------------------------------
                                                                       2000             1999            1998
                                                                   ------------     ------------    ------------
                                                                                   (in thousands)
                                                                                         
   Oil and Gas Producing Activities:
     Oil and gas sales, net of production costs                   $        (583)   $        (241)  $        (116)
     Net changes in prices and production costs                             932            1,084          (1,115)
     Revisions of previous quantity estimates                               257            2,216            (238)
     Accretion of discount                                                  248               30             167
     Changes in production rates, timing and other                          (93)            (906)            (65)
                                                                   ------------     ------------    ------------

     Change in present value of future net revenues                         761            2,183          (1,367)
                                                                   ------------     ------------    ------------

     Balance, beginning of year                                           2,484              301           1,668
                                                                   ------------     ------------    ------------

     Balance, end of year                                         $       3,245    $       2,484   $         301
                                                                   ============     ============    ============


NOTE 8.    MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                                2000              1999             1998
                                                              --------          --------         --------

                                                                                        
                  Plains Marketing, L.P.                         64%               62%                -
                  Genesis Crude Oil, L.P.                         -                 -                69%
                  Western Gas Resources, Inc.                     2%                3%               13%


       At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $48,722 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

       Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

       The following is a brief summary of the more significant provisions of
the limited partnership agreement:

       Managing general partner - The managing general partner of the
       Partnership is Pioneer USA. Pioneer USA has the power and authority to
       manage, control and administer all Program and Partnership affairs. As
       managing general partner and operator of the Partnership's properties,
       all production expenses are incurred by Pioneer USA and billed to the
       Partnership. The majority of the Partnership's oil and gas revenues are
       received directly by the Partnership, however, a portion of the oil and
       gas revenue is initially received by Pioneer USA prior to being paid to
       the Partnership. Under the Partnership agreement, the managing general
       partner pays



                                       19

   1565



       1% of the Partnership's acquisition, drilling and completion costs and 1%
       of its operating and general and administrative expenses. In return, it
       is allocated 1% of the Partnership's revenues.

       Limited partner liability - The maximum amount of liability of any
       limited partner is the total contributions of such partner plus his share
       of any undistributed profits.

       Initial capital contributions - The partners entered into subscription
       agreements for aggregate capital contributions of $7,531,000. Pioneer USA
       is required to contribute amounts equal to 1% of initial Partnership
       capital less commission and organization and offering costs allocated to
       the limited partners and to contribute amounts necessary to pay costs and
       expenses allocated to it under the Partnership agreement to the extent
       its share of revenues does not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
            FINANCIAL DISCLOSURE

None.


                                       20

   1566



                                    PART III

ITEM 10.   DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                               Age at
                                            December 31,
        Name                                    2000                              Position
        ----                                    ----                              --------

                                                            
Scott D. Sheffield                               48                 President

Timothy L. Dove                                  44                 Executive Vice President, Chief
                                                                      Financial Officer and Director

Dennis E. Fagerstone                             51                 Executive Vice President and Director

Mark L. Withrow                                  53                 Executive Vice President, General
                                                                      Counsel and Director

Danny Kellum                                     46                 Executive Vice President - Domestic
                                                                      Operations and Director

Rich Dealy                                       34                 Vice President and Chief Accounting
                                                                      Officer


         Scott D. Sheffield.  Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.


                                       21

   1567



       Timothy L. Dove.  Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

       Dennis E. Fagerstone.  Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

       Mark L. Withrow.  Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

       Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

       Rich Dealy.  Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.


                                       22

   1568



ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 15% during the first three years
and approximately 20% after three years of its operating and general and
administrative expenses. In return, they are allocated approximately 15% during
the first three years and approximately 20% after three years of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers of
Pioneer USA, but does pay a portion of Pioneer USA's general and administrative
expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)      Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 30 limited partner interests at January 1, 2001.

(b)      Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:




                                       23

   1569





                                                                   2000              1999             1998
                                                              -------------     -------------    -------------
                                                                                       
    Payment of lease operating and supervision
       charges in accordance with standard
       industry operating agreements                          $   130,806       $  126,701       $   124,074

    Reimbursement of general and administrative
       expenses                                               $    27,439       $   16,060       $    12,838


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.


                                       24

   1570



                                     PART IV

ITEM 14.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)    1.    Financial statements

             The following are filed as part of this Report:

                    Independent Auditors' Report

                    Balance sheets as of December 31, 2000 and 1999

                    Statements of operations for the years ended December 31,
                      2000, 1999 and 1998

                    Statements of partners' capital for the years ended December
                      31, 2000, 1999 and 1998

                    Statements of cash flows for the years ended December 31,
                      2000, 1999 and 1998

                    Notes to financial statements

       2.    Financial statement schedules

             All financial statement schedules have been omitted since the
             required information is in the financial statements or notes
             thereto, or is not applicable nor required.

(b)    Reports on Form 8-K

None.

(c)    Exhibits

       The exhibits listed on the accompanying index to exhibits are filed or
       incorporated by reference as part of this Report.


                                       25

   1571



                               S I G N A T U R E S

       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                          PARKER & PARSLEY 90-C CONV., L.P.

Dated: March 26, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:     /s/ Scott D. Sheffield
                                                  ------------------------------
                                                  Scott D. Sheffield, President

       Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                                       
/s/ Scott D. Sheffield                      President of Pioneer USA                           March 26, 2001
--------------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                         Executive Vice President, Chief                    March 26, 2001
--------------------------------------      Financial Officer and Director of
Timothy L. Dove                             Pioneer USA


/s/ Dennis E. Fagerstone                    Executive Vice President and                       March 26, 2001
--------------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                         Executive Vice President, General                  March 26, 2001
--------------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                            Executive Vice President - Domestic                March 26, 2001
--------------------------------------      Operations and Director of Pioneer
Danny Kellum                                USA


/s/ Rich Dealy                              Vice President and Chief Accounting                March 26, 2001
--------------------------------------      Officer of Pioneer USA
Rich Dealy



                                       26

   1572


                        PARKER & PARSLEY 90-C CONV., L.P.

                                INDEX TO EXHIBITS

       The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                               Description                                                Page
-----------                               -----------                                                ----

                                                                                            
   3(a)                      Form of Agreement of Limited Partnership                                 -
                             of Parker & Parsley 90-C Conv., L.P.
                             incorporated by reference to Exhibit A of
                             the Post-Effective Amendment No. 1 of
                             the Partnership's Registration Statement
                             on Form S-1 (Registration No. 33-26097)

   4(b)                      Form of Limited Partner Subscription Agreement                           -
                             incorporated by reference to Exhibit C of the
                             Post-Effective Amendment No. 1 of the
                             Partnership's Registration Statement on Form
                             S-1 (Registration No. 33-26097)

   4(b)                      Form of General Partner Subscription Agreement                           -
                             incorporated by reference to Exhibit D of the
                             Post-Effective Amendment No. 1 of the
                             Partnership's Registration Statement on Form
                             S-1 (Registration No. 33-26097)

   4(b)                      Power of Attorney incorporated by reference to                           -
                             Exhibit B of Amendment No. 1 of the Partnership's
                             Registration Statement on Form S-1
                             (Registration No. 33-26097)

   4(c)                      Specimen Certificate of Limited Partnership                              -
                             Interest incorporated by reference to Exhibit 4c
                             of the Partnership's Registration Statement on
                             Form S-1 (Registration No. 33-26097)

  10(b)                      Form of Development Drilling Program                                     -
                             Agreement incorporated by reference to Exhibit
                             B of the Post-Effective Amendment No. 1 of
                             the Partnership's Registration Statement on
                             Form S-1 (Registration No. 33-26097)





                                       27

   1573




                        PARKER & PARSLEY 90-C CONV., L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  193,711   $  917,184   $  537,893   $  430,499   $  661,475   $  837,849
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  185,784   $   79,288   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   91,821   $  509,518   $  137,106   $ (258,625)  $  105,740   $  359,349
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
        partner                    $          $      918   $    5,095   $    1,371   $   (2,586)  $    1,057   $    3,593
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $   90,903   $  504,423   $  135,735   $ (256,039)  $  104,683   $  355,756
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
    (loss) per limited
    partnership interest           $          $    12.07   $    66.98   $    18.02   $   (34.00)  $    13.90   $    47.24
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    13.62   $    65.37   $    18.04   $    17.30   $    47.53   $    51.98
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,004,603   $1,023,864   $1,014,263   $1,011,034   $1,411,804   $1,661,127
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1574
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 90-C, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

               PROXY STATEMENT/PROSPECTUS DATED           , 2001

                                   ----------

                THE DATE OF THIS SUPPLEMENT IS           , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
90-C, L.P., and supplements the proxy statement/prospectus dated               ,
2001, of Pioneer Natural Resources Company and Pioneer Natural Resources USA,
Inc., by which Pioneer USA is soliciting proxies to be voted at a special
meeting of limited partners of the partnership. The purpose of the special
meeting is for you to vote upon the merger of the partnership with and into
Pioneer USA that, if completed, will result in your receiving common stock of
Pioneer Natural Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 90-C, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000



                                      -1-
   1575


                           PARKER & PARSLEY 90-C, L.P.

                         SUPPLEMENTAL INFORMATION TABLE



                                                                                                       
Aggregate Initial Investment by the Limited Partners(a)                                                   $     12,107

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                               $      7,958

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer USA(a), (b)     $      2,939

Merger Value per $1,000 Limited Partner Investment(b), (c)                                                $     243.26

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for                             3.31 times
the past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

      --    as of March 31, 2001(c)                                                                       $     125.95

      --    as of December 31, 2000(c)                                                                    $     131.96

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                                         $     225.46

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                           $     236.05

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)             $        149



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2039, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.


                                      -2-
   1576



                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-26097-09


                           PARKER & PARSLEY 90-C, L.P.
             (Exact name of Registrant as specified in its charter)

                    Delaware                           75-2347262
         -------------------------------         ---------------------
         (State or other jurisdiction of            (I.R.S. Employer
         incorporation or organization)          Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas     75039
----------------------------------------------------------------   ----------
            (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]






   1577



                           PARKER & PARSLEY 90-C, L.P.

                                TABLE OF CONTENTS




                                                                        Page
                          Part I. Financial Information
                                                                

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000......................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000...........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001....................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000...........................    6

            Notes to Financial Statements.............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K..........................   10

            Signatures................................................   11




                                        2
   1578



                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                          Part I. Financial Information

Item 1.     Financial Statements

                                 BALANCE SHEETS



                                                     March 31,      December 31,
                                                       2001             2000
                                                    -----------     -----------
                                                    (Unaudited)
                                                              
                 ASSETS

Current assets:
  Cash                                              $    147,262    $    162,620
  Accounts receivable - oil and gas sales                170,995         191,950
                                                    ------------    ------------
        Total current assets                             318,257         354,570
                                                    ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                 9,324,542       9,321,783
Accumulated depletion                                 (8,061,760)     (8,040,111)
                                                    ------------    ------------
        Net oil and gas properties                     1,262,782       1,281,672
                                                    ------------    ------------
                                                    $  1,581,039    $  1,636,242
                                                    ============    ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable:
    Affiliate                                       $     28,310    $     22,567
    Other                                                 12,559              --
                                                    ------------    ------------
                                                          40,869          22,567
                                                    ------------    ------------
Partners' capital:
  Managing general partner                                15,352          16,087
  Limited partners (12,107 interests)                  1,524,818       1,597,588
                                                    ------------    ------------
                                                       1,540,170       1,613,675
                                                    ------------    ------------
                                                    $  1,581,039    $  1,636,242
                                                    ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   1579


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)



                                                       Three months ended
                                                            March 31,
                                                     -----------------------
                                                        2001         2000
                                                     ----------   ----------
                                                            

Revenues:
   Oil and gas                                       $  371,240   $  311,387
   Interest                                               2,808        2,324
                                                     ----------   ----------
                                                        374,048      313,711
                                                     ----------   ----------
Costs and expenses:
   Oil and gas production                               153,745      134,566
   General and administrative                            13,096        9,539
   Depletion                                             21,649       22,108
                                                     ----------   ----------
                                                        188,490      166,213
                                                     ----------   ----------
Net income                                           $  185,558   $  147,498
                                                     ==========   ==========
Allocation of net income:
   Managing general partner                          $    1,856   $    1,475
                                                     ==========   ==========
   Limited partners                                  $  183,702   $  146,023
                                                     ==========   ==========
Net income per limited partnership interest          $    15.17   $    12.06
                                                     ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.




                                        4
   1580



                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)




                                   Managing
                                    general        Limited
                                    partner        partners         Total
                                 ------------    ------------    ------------
                                                        

Balance at January 1, 2001       $     16,087    $  1,597,588    $  1,613,675

    Distributions                      (2,591)       (256,472)       (259,063)

    Net income                          1,856         183,702         185,558
                                 ------------    ------------    ------------

Balance at March 31, 2001        $     15,352    $  1,524,818    $  1,540,170
                                 ============    ============    ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5

   1581

                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                      Three months ended
                                                           March 31,
                                                     ----------------------
                                                        2001         2000
                                                     ---------    ---------
                                                              
Cash flows from operating activities:
 Net income                                          $ 185,558    $ 147,498
 Adjustments to reconcile net income to net
    cash provided by operating activities:
      Depletion                                         21,649       22,108
 Changes in assets and liabilities:
      Accounts receivable                               20,955        5,698
      Accounts payable                                  18,302        3,413
                                                     ---------    ---------
       Net cash provided by operating activities       246,464      178,717
                                                     ---------    ---------
Cash flows used in investing activities:
 Additions to oil and gas properties                    (2,759)     (11,065)

Cash flows used in financing activities:
 Cash distributions to partners                       (259,063)    (166,511)
                                                     ---------    ---------
Net increase (decrease) in cash                        (15,358)       1,141
Cash at beginning of period                            162,620      164,100
                                                     ---------    ---------
Cash at end of period                                $ 147,262    $ 165,241
                                                     =========    =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        6

   1582



                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 90-C, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 19% to $371,240 for the three
months ended March 31, 2001 as compared to $311,387 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 9,339
barrels of oil, 1,379 barrels of natural gas liquids ("NGLs") and 13,106 mcf of
gas were sold, or 12,902 barrel of oil equivalents ("BOEs"). For the three



                                        7

   1583



months ended March 31, 2000, 9,323 barrels of oil, 3,126 barrels of NGLs and
10,341 mcf of gas were sold, or 14,173 BOEs.

The average price received per barrel of oil increased $.92, or 3%, from $27.16
for the three months ended March 31, 2000 to $28.08 for the same period in 2001.
The average price received per barrel of NGLs increased $6.00, or 46%, from
$12.95 for the three months ended March 31, 2000 to $18.95 for the same period
in 2001. The average price received per mcf of gas increased 270% from $1.71
during the three months ended March 31, 2000 to $6.33 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $188,490 for the three months ended March
31, 2001 as compared to $166,213 for the same period in 2000, an increase of
$22,277, or 13%. This increase was primarily due to increases in production
costs and general and administrative expenses ("G&A"), offset by a decline in
depletion.

Production costs were $153,745 for the three months ended March 31, 2001 and
$134,566 for the same period in 2000, resulting in an increase of $19,179, or
14%. The increase was primarily due to additional well maintenance costs
incurred to stimulate well production and higher production taxes associated
with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 37% from $9,539 for the three months ended March 31, 2000 to $13,096
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual of tax preparation fees.

Depletion was $21,649 for the three months ended March 31, 2001 as compared to
$22,108 for the same period in 2000, a decrease of $459, or 2%. This decrease
was primarily due to positive revisions to proved reserves on one well during
the three months ended March 31, 2001.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $67,747 during the three
months ended March 31, 2001 from the same period in 2000. The increase was
primarily attributable to an increase of $60,337 in oil and gas sales receipts
and a reduction in working capital of $30,146, offset by increases in production
costs of $19,179 and G&A expenses of $3,557. The increase in oil and gas
receipts resulted from the increase in commodity prices during 2001 which

                                        8

   1584



contributed an additional $75,502 to oil and gas receipts, offset by $15,165
resulting from the decline in production during 2001 as compared to the same
period in 2000. The increase in production costs was primarily due to additional
well maintenance costs incurred to stimulate well production and higher
production taxes associated with higher oil and gas prices. The increase in G&A
was primarily due to a higher percentage of the managing general partner's G&A
being allocated (limited to 3% of oil and gas revenues) as a result of increased
oil and gas revenues and an increase in the accrual of tax preparation fees.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 were related to expenditures for upgrades of oil and gas
equipment on active properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $259,063, of which $2,591 was distributed to the managing general partner
and $256,472 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $166,511, of which $1,665 was
distributed to the managing general partner and $164,846 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)      "Item 2. Management's Discussion and Analysis of Financial Condition
         and Results of Operations" contains forward looking statements that
         involve risks and uncertainties. Accordingly, no assurances can be
         given that the actual events and results will not be materially
         different than the anticipated results described in the forward looking
         statements.


                                       9


   1585



                           Part II. Other Information


Item 6.          Exhibits and Reports on Form 8-K

(a)      Exhibits - none

(b)      Reports on Form 8-K - none.










                                        10

   1586


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 90-C, L.P.



                                   By:      Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 11, 2001               By:      /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer











                                       11

   1587
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-26097-09


                           PARKER & PARSLEY 90-C, L.P.
             (Exact name of Registrant as specified in its charter)

         DELAWARE                                       75-2347262
--------------------------------                  -------------------------
(State or other jurisdiction of                        (I.R.S. Employer
incorporation or organization)                      Identification Number)



                                                                           
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                 75039
----------------------------------------------------------------              ------------
          (Address of principal executive offices)                            (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
          Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$12,080,000.

       As of March 8, 2001, the number of outstanding limited partnership
interests was 12,107.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None
Parts I and II of this annual report on Form 10-K (the "Report") contain forward
looking statements that involve risks and uncertainties. Accordingly, no
assurances can be given that the actual events and results will not be
materially different than the anticipated results described in the forward
looking statements. See "Item 1. Business" for a description of various factors
that could materially affect the ability of the Partnership to achieve the
anticipated results described in the forward looking statements.
   1588






                                     PART I

ITEM 1.        BUSINESS

Parker & Parsley 90-C, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 12,107 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 64% was attributable to sales made to
Plains Marketing, L.P. Pioneer USA is of the opinion that the loss of any one
purchaser would not have an adverse effect on its ability to sell its oil,
natural gas liquids ("NGLs") and gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial liability due to pollution and other
environmental damages. Although the Partnership believes that



                                       2
   1589


its business operations do not impair environmental quality and that its costs
of complying with any applicable environmental regulations are not currently
significant, the Partnership cannot predict what, if any, effect these
environmental regulations may have on its current or future operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.       PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas are located. Such property interests are often subject to
landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 44
oil and gas wells. One well was sold and one well was plugged and abandoned due
to uneconomical operations. At December 31, 2000, the Partnership had 42
producing oil and gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998 and changes in such quantities for
the years then ended, see Note 7 of Notes to Financial Statements included in
"Item 8. Financial Statements and Supplementary Data" below. Such reserves have
been evaluated by Williamson Petroleum Consultants, Inc., an independent
petroleum consultant.

ITEM 3.       LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.       SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.




                                       3
   1590


                                     PART II


ITEM 5.       MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
                DISTRIBUTIONS

At March 8, 2001, the Partnership had 12,107 outstanding limited partnership
interests held of record by 901 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, $791,434 and $218,354, respectively,
of such revenue-related distributions were made to the limited partners.

ITEM 6.         SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                        2000         1999         1998         1997         1996
                                     ----------   ----------   ----------   ----------   -----------
                                                                          
Operating results:
-----------------
  Oil and gas sales                  $1,474,499   $  864,722   $  692,090   $1,063,396   $ 1,346,937
                                     ==========   ==========   ==========   ==========   ===========

  Impairment of oil and gas
    properties                       $       --   $       --   $  298,622   $  127,213   $        --
                                     ==========   ==========   ==========   ==========   ===========

  Net income (loss)                  $  818,778   $  220,855   $ (416,064)  $  168,261   $   577,803
                                     ==========   ==========   ==========   ==========   ===========

  Allocation of net income
    (loss):
    Managing general partner         $    8,188   $    2,209   $   (4,161)  $    1,683   $     5,778
                                     ==========   ==========   ==========   ==========   ===========

    Limited partners                 $  810,590   $  218,646   $ (411,903)  $  166,578   $   572,025
                                     ==========   ==========   ==========   ==========   ===========

  Limited partners' net income
    (loss) per limited
    partnership interest             $    66.95   $    18.06   $   (34.02)  $    13.76   $     47.25
                                     ==========   ==========   ==========   ==========   ===========

  Limited partners' cash
    distributions per limited
    partnership interest             $    65.37   $    18.04   $    17.30   $    47.53   $     51.98
                                     ==========   ==========   ==========   ==========   ===========

At year end:
-------------
  Identifiable assets                $1,636,242   $1,621,156   $1,617,114   $2,261,689   $ 2,664,141
                                     ==========   ==========   ==========   ==========   ===========





                                       4
   1591


ITEM 7.        MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
                 RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 71% to $1,474,499 for 2000 as
compared to $864,722 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 37,944 barrels
of oil, 14,742 barrels of natural gas liquids ("NGLs") and 48,907 mcf of gas
were sold, or 60,837 barrel of oil equivalents ("BOEs"). In 1999, 37,886 barrels
of oil, 14,547 barrels of NGLs and 47,265 mcf of gas were sold, or 60,311 BOEs.
Due to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.21, or 71%, from
$17.13 in 1999 to $29.34 in 2000. The average price received per barrel of NGLs
increased $5.60, or 60%, from $9.31 in 1999 to $14.91 in 2000. The average price
received per mcf of gas increased 70% from $1.70 in 1999 to $2.89 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Gains on disposition of assets of $624 and $167 recognized during 2000 and 1999,
respectively, were due to equipment credits received on a fully depleted well in
each year.

Total costs and expenses increased in 2000 to $669,449 as compared to $650,544
in 1999, an increase of $18,905, or 3%. This increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $537,048 in 2000 and $477,835 in 1999, resulting in an
increase of $59,213, or 12%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period G&A increased
47% from $33,223 in 1999 to $48,801 in 2000 primarily due to a higher percentage
of the managing general partner's G&A being allocated (limited to 3% of oil and
gas revenues) as a result of increased oil and gas revenues. The Partnership
paid the managing general partner $44,112 in 2000 and $25,818 in 1999 for G&A
incurred on behalf of the Partnership. The remaining G&A was paid directly by
the Partnership. The managing general partner determines the allocated expenses
based upon the level of activity of the Partnership relative to the
non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.






                                       5
   1592


Depletion was $83,600 in 2000 compared to $139,486 in 1999, representing a
decrease of $55,886, or 40%. This decrease was primarily due to a 50,718 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 25% to $864,722 from
$692,090 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 37,886 barrels of oil,
14,547 barrels of NGLs and 47,265 mcf of gas were sold, or 60,311 BOEs. In 1998,
39,380 barrels of oil, 13,978 barrels of NGLs and 48,787 mcf of gas were sold,
or 61,489 BOEs.

The average price received per barrel of oil increased $3.89, or 29%, from
$13.24 in 1998 to $17.13 in 1999. The average price received per barrel of NGLs
increased $2.51, or 37%, from $6.80 in 1998 to $9.31 in 1999. The average price
received per mcf of gas increased 10% from $1.55 in 1998 to $1.70 in 1999.

Total costs and expenses decreased in 1999 to $650,544 as compared to $1,115,454
in 1998, a decrease of $464,910, or 42%. This decrease was due to declines in
the impairment of oil and gas properties, depletion and production costs, offset
by an increase in G&A.

Production costs were $477,835 in 1999 and $505,571 in 1998, resulting in a
$27,736 decrease, or 5%. The decrease was due to declines in well maintenance
costs and ad valorem taxes, offset by an increase in production taxes

During this period G&A increased 37% from $24,190 in 1998 to $33,223 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $25,818 in
1999 and $20,639 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $298,622 related to its oil and gas properties during 1998.

Depletion was $139,486 in 1999 compared to $287,071 in 1998. This represented a
decrease of $147,585, or 51%. This decrease was primarily the result of an
increase in proved reserves of 332,733 barrels of oil during 1999 as a result of
higher commodity prices and a reduction in the Partnership's net depletable
basis from charges taken in accordance with SFAS 121 during the fourth quarter
of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998,



                                       6
   1593

weather patterns, regional economic recessions and political matters combined to
cause worldwide oil supplies to exceed demand resulting in a substantial decline
in oil prices. Also during 1998, but to a lesser extent, market prices for
natural gas declined. During 1999 and 2000, the Organization of Petroleum
Exporting Countries ("OPEC") and certain other crude oil exporting nations
announced reductions in their planned export volumes. Those announcements,
together with the enactment of the announced reductions in export volumes, had a
positive impact on world oil prices, as have overall natural gas supply and
demand fundamentals on North American natural gas prices. Although the favorable
commodity price environment and stable field service cost environment is
expected to continue during 2001, there is no assurance that commodity prices
will not return to a less favorable level or that field service costs will not
escalate in the future, both of which could negatively impact the Partnership's
future results of operations and cash distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $532,008 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $616,371, offset by increases in production costs paid
of $59,213, G&A expenses paid of $15,578 and working capital of $9,572. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $607,017 to oil and gas receipts and
an increase of $9,354 resulting from the increase in production during 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active oil and gas properties.

Proceeds from disposition of assets of $624 and $167 recognized during 2000 and
1999, respectively, were related to equipment credits received on a fully
depleted well in each year.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $799,428, of which $7,994 was
distributed to the managing general partner and $791,434 to the limited
partners. In 1999, cash distributions to the partners were $220,560, of which
$2,206 was distributed to the managing general partner and $218,354 to the
limited partners.





                                       7
   1594


ITEM 8.      FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS


                                                                                         Page
                                                                                         ----
                                                                                     
Financial Statements of Parker & Parsley 90-C, L.P.:
 Independent Auditors' Report.........................................................     9
 Balance Sheets as of December 31, 2000 and 1999......................................    10
 Statements of Operations for the Years Ended December 31,
   2000, 1999 and 1998................................................................    11
 Statements of Partners' Capital for the Years Ended
   December 31, 2000, 1999 and 1998...................................................    12
 Statements of Cash Flows for the Years Ended December 31,
   2000, 1999 and 1998................................................................    13
 Notes to Financial Statements........................................................    14





                                       8
   1595




                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90-C, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90-C, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90-C, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                   Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       9
   1596


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                   2000             1999
                                                             ---------------- ----------------
              ASSETS
              ------

Current assets:
                                                                          
  Cash                                                         $   162,620      $   164,100
  Accounts receivable - oil and gas sales                          191,950          128,379
                                                                 ---------        ---------

       Total current assets                                        354,570          292,479
                                                                 ---------        ---------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                           9,321,783        9,285,188
Accumulated depletion                                           (8,040,111)      (7,956,511)
                                                                 ---------        ---------

       Net oil and gas properties                                1,281,672        1,328,677
                                                                 ---------        ---------

                                                               $ 1,636,242      $ 1,621,156
                                                                 =========        =========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                 $    22,567      $    26,831

Partners' capital:
  Managing general partner                                          16,087           15,893
  Limited partners (12,107 interests)                            1,597,588        1,578,432
                                                                 ---------        ---------

                                                                 1,613,675        1,594,325

                                                               $ 1,636,242      $ 1,621,156
                                                                 =========        =========

















   The accompanying notes are an integral part of these financial statements.



                                       10
   1597


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                         2000          1999          1998
                                                     -----------   -----------   -----------

Revenues:
                                                                        
  Oil and gas                                        $ 1,474,499   $   864,722   $   692,090
  Interest                                                13,104         6,510         7,300
  Gain on disposition of assets                              624           167            --
                                                     -----------   -----------   -----------

                                                       1,488,227       871,399       699,390
                                                     -----------   -----------   -----------

Costs and expenses:
  Oil and gas production                                 537,048       477,835       505,571
  General and administrative                              48,801        33,223        24,190
  Impairment of oil and gas properties                        --            --       298,622
  Depletion                                               83,600       139,486       287,071
                                                     -----------   -----------   -----------

                                                         669,449       650,544     1,115,454
                                                     -----------   -----------   -----------

Net income (loss)                                    $   818,778   $   220,855   $  (416,064)
                                                     ===========   ===========   ===========

Allocation of net income (loss):
  Managing general partner                           $     8,188   $     2,209   $    (4,161)
                                                     ===========   ===========   ===========

  Limited partners                                   $   810,590   $   218,646   $  (411,903)
                                                     ===========   ===========   ===========

Net income (loss) per limited partnership interest   $     66.95   $     18.06   $    (34.02)
                                                     ===========   ===========   ===========




















   The accompanying notes are an integral part of these financial statements.



                                       11
   1598


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                     Managing
                                                      general       Limited
                                                      partner       partners         Total
                                                  -------------- -------------- ----------------


                                                                       
Partners' capital at January 1, 1998              $  22,166      $2,199,485     $2,221,651

   Distributions                                     (2,115)       (209,442)      (211,557)

   Net loss                                          (4,161)       (411,903)      (416,064)
                                                    -------        --------       --------

Partners' capital at December 31, 1998               15,890       1,578,140      1,594,030

   Distributions                                     (2,206)       (218,354)      (220,560)

   Net income                                         2,209         218,646        220,855
                                                    -------        --------       --------

Partners' capital at December 31, 1999               15,893       1,578,432      1,594,325

   Distributions                                     (7,994)       (791,434)      (799,428)

   Net income                                         8,188         810,590        818,778
                                                    -------        --------       --------

Partners' capital at December 31, 2000            $  16,087      $1,597,588     $1,613,675
                                                   ========       =========      =========






















   The accompanying notes are an integral part of these financial statements.



                                       12
   1599


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                        2000          1999           1998
                                                   ------------  -------------- ---------------
                                                                       
Cash flows from operating activities:
   Net income (loss)                               $ 818,778     $ 220,855      $(416,064)
   Adjustments to reconcile net income (loss)
     to net cash provided by operating
     activities:
       Impairment of oil and gas properties              -             -          298,622
       Depletion                                      83,600       139,486        287,071
       Gain on disposition of assets                    (624)         (167)           -
   Changes in assets and liabilities:
       Accounts receivable                           (63,571)      (62,010)        45,989
       Accounts payable                               (4,264)        3,747        (16,954)
                                                     -------       -------        -------

         Net cash provided by operating
           activities                                833,919       301,911        198,664
                                                     -------       -------        -------

Cash flows from investing activities:
   Additions to oil and gas properties               (36,595)      (16,900)       (21,456)
   Proceeds from disposition of assets                   624           167            -
                                                     -------       -------        -------

         Net cash used in investing activities       (35,971)      (16,733)       (21,456)
                                                     -------       -------        -------

Cash flows used in financing activities:
   Cash distributions to partners                   (799,428)     (220,560)      (211,557)
                                                     --------      --------       --------

Net increase (decrease) in cash                       (1,480)       64,618        (34,349)
Cash at beginning of year                            164,100        99,482        133,831
                                                     -------       -------        -------

Cash at end of year                                $ 162,620     $ 164,100      $  99,482
                                                    ========      ========       ========


















   The accompanying notes are an integral part of these financial statements.



                                       13
   1600


                           PARKER & PARSLEY 90-C, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1.       ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 90-C, L.P. (the "Partnership") is a limited partnership
organized in 1990 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2.       SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

      Net income (loss) per limited partnership interest - The net income (loss)
per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

      Income taxes - A Federal income tax provision has not been included in the
financial statements as the income (loss) of the Partnership is included in the
individual Federal income tax returns of the respective partners.



                                       14
   1601

      Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

      General and administrative expenses - General and administrative expenses
are allocated in part to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

      Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

      Environmental - The Partnership is subject to extensive federal, state and
local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

      Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.       IMPAIRMENT OF LONG-LIVED ASSETS

      In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $298,622 related to
its proved oil and gas properties during 1998.



                                       15
   1602

NOTE 4.       INCOME TAXES

      The financial statement basis of the Partnership's net assets and
liabilities was $81,171 less than the tax basis at December 31, 2000.

      The following is a reconciliation of net income (loss) per statements of
operations with the net income (loss) per Federal income tax returns for the
years ended December 31:



                                                           2000         1999         1998
                                                         ---------    ---------    ---------
                                                                          
    Net income (loss) per statements of operations       $ 818,778    $ 220,855    $(416,064)
    Depletion and depreciation provisions for tax
      reporting purposes less than amounts for
      financial reporting purposes                          64,630      123,267       81,152
    Impairment of oil and gas properties for financial
      reporting purposes                                        --           --      298,622
    Intangible development costs capitalized for
      financial reporting purposes and expensed for
      tax reporting purposes                                  (619)          --           --
    Other, net                                              (1,775)      (4,424)       4,552
                                                         ---------    ---------    ---------

          Net income (loss) per Federal income
            tax return                                   $ 881,014    $ 339,698    $ (31,738)
                                                         =========    =========    =========


NOTE 5.       OIL AND GAS PRODUCING ACTIVITIES

      The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                      2000          1999           1998
                                                   -----------  -------------  --------------
                                                                       
      Development costs                            $  36,595     $  16,900      $  21,456
                                                    ========      ========       ========


               Capitalized oil and gas properties consist of the following:



                                                                                  2000           1999
                                                                              -----------    -----------
                                                                                       
    Proved properties:
      Property acquisition costs                                              $   364,450    $   364,450
      Completed wells and equipment                                             8,957,333      8,920,738
                                                                              -----------    -----------

                                                                                9,321,783      9,285,188
    Accumulated depletion                                                      (8,040,111)    (7,956,511)
                                                                              -----------    -----------

          Net oil and gas properties                                          $ 1,281,672    $ 1,328,677
                                                                              ===========    ===========


NOTE 6.      RELATED PARTY TRANSACTIONS

    Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:




                                                                     2000          1999           1998
                                                                 ------------ -------------- --------------
                                                                                      
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                               $ 210,287     $  203,686     $ 199,461

    Reimbursement of general and administrative
      expenses                                                    $  44,112     $   25,818     $  20,639




                                       16
   1603

      The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA
and P&P Employees 90-C Conv., L.P. ("EMPL") (the "Entities"), Parker & Parsley
90-C Conv., L.P. and the Partnership (the "Partnerships") are parties to the
Program agreement. EMPL is a limited partnership organized for the benefit of
certain employees of Pioneer USA. EMPL was merged with Pioneer USA on December
28, 2000.

      The costs and revenues of the Program are allocated to Pioneer USA and the
Partnerships as follows:


                                                              Pioneer USA (1)  Partnerships(2)
                                                              ---------------  ---------------
                                                                           
    Revenues:
      Proceeds from disposition of depreciable and depletable
        properties:
        First three years                                       14.141414%       85.858586%
        After first three years                                 19.191919%       80.808081%
      All other revenues:
        First three years                                       14.141414%       85.858586%
        After first three years                                 19.191919%       80.808081%
    Costs and expenses:
      Lease acquisition costs, drilling and completion costs
        and all other costs                                      9.090909%       90.909091%
      Operating costs, reporting and legal expenses and
        general and administrative expenses:
        First three years                                       14.141414%       85.858586%
        After first three years                                 19.191919%       80.808081%


      (1)   Excludes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 27 limited partner interests
            owned by Pioneer USA.

      (2)   The allocation between the Partnership and Parker & Parsley 90-C
            Conv., L.P. is 61.650881% and 38.349119%, respectively.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

      The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                                               Oil and NGLs         Gas
                                                                  (bbls)           (mcf)
                                                              -------------     ------------
                                                                           
    Net proved reserves at January 1, 1998                       682,212           685,617
    Revisions                                                   (327,935)         (275,264)
    Production                                                   (53,358)          (48,787)
                                                                --------          --------

    Net proved reserves at December 31, 1998                     300,919           361,566
    Revisions                                                    472,259           575,173
    Production                                                   (52,433)          (47,265)
                                                                --------          --------

    Net proved reserves at December 31, 1999                     720,745           889,474
    Revisions                                                     82,135           (88,650)
    Production                                                   (52,686)          (48,907)
                                                                --------          --------

    Net proved reserves at December 31, 2000                     750,194           751,917
                                                                ========          ========




                                       17
   1604

      As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.22 per barrel of NGLs and $7.80 per mcf of gas,
discounted at 10% was approximately $5,217,000 and undiscounted was $10,234,000.

      Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

     The standardized measure of discounted future net cash flows is computed by
applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

     Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                              For the years ended December 31,
                                                             ----------------------------------
                                                               2000        1999        1998
                                                             --------    --------    --------
                                                                      (in thousands)
                                                                            
Oil and gas producing activities:
  Future cash inflows                                        $ 22,838    $ 17,942    $  3,279
  Future production costs                                     (12,604)    (10,399)     (2,609)
                                                             --------    --------    --------

                                                               10,234       7,543         670
  10% annual discount factor                                   (5,017)     (3,552)       (187)
                                                             --------    --------    --------

  Standardized measure of discounted future net cash flows   $  5,217    $  3,991    $    483
                                                             ========    ========    ========





                                       18
   1605



                                                            For the years ended December 31,
                                                       ----------------------------------------
                                                           2000         1999          1998
                                                         --------     ---------     --------
                                                                   (in thousands)
  Oil and Gas Producing Activities:
                                                                         
    Oil and gas sales, net of production costs         $     (937)  $      (387)  $     (187)
    Net changes in prices and production costs              1,497         1,742       (1,792)
    Revisions of previous quantity estimates                  417         3,560         (381)
    Accretion of discount                                     399            48          268
    Changes in production rates, timing and other            (150)       (1,455)        (105)
                                                         --------     ---------     --------

    Change in present value of future net revenues          1,226         3,508       (2,197)
                                                         --------     ---------     --------

    Balance, beginning of year                              3,991           483        2,680
                                                         --------     ---------     --------

    Balance, end of year                               $    5,217   $     3,991   $      483
                                                        =========    ==========    =========


NOTE 8.      MAJOR CUSTOMERS

     The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:


                                                     2000          1999           1998
                                                   --------      --------       --------

                                                                         
              Plains Marketing, L.P.                  64%            62%            -
              Genesis Crude Oil, L.P.                  -              -            69%
              Western Gas Resources, Inc.              2%             3%           13%


      At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $78,327 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

      Pioneer USA is of the opinion that the loss of any one purchaser would not
have an adverse effect on the ability of the Partnership to sell its oil, NGLs
and gas production.

NOTE 9.       PARTNERSHIP AGREEMENT

      The following is a brief summary of the more significant provisions of the
limited partnership agreement:

      Managing general partner - The managing general partner of the Partnership
      is Pioneer USA. Pioneer USA has the power and authority to manage, control
      and administer all Program and Partnership affairs. As managing general
      partner and operator of the Partnership's properties, all production
      expenses are incurred by Pioneer USA and billed to the Partnership. The
      majority of the Partnership's oil and gas revenues are received directly
      by the Partnership, however, a portion of the oil and gas revenue is
      initially received by Pioneer USA prior to being paid to the Partnership.
      Under the Partnership agreement, the managing general partner pays 1% of
      the Partnership's acquisition, drilling and completion costs and 1% of its
      operating and general and administrative expenses. In return, it is
      allocated 1% of the Partnership's revenues.

                                       19
   1606

      Limited partner liability - The maximum amount of liability of any limited
      partner is the total contributions of such partner plus his share of any
      undistributed profits.

      Initial capital contributions - The limited partners entered into
      subscription agreements for aggregate capital contributions of
      $12,107,000. The managing general partner is required to contribute
      amounts equal to 1% of initial Partnership capital less commission and
      organization and offering costs allocated to the limited partners and to
      contribute amounts necessary to pay costs and expenses allocated to it
      under the Partnership agreement to the extent its share of revenues does
      not cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
             AND FINANCIAL DISCLOSURE

None.



                                       20
   1607


                                    PART III

ITEM 10.   DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                       Age at
                                    December 31,
       Name                             2000                       Position
       ----                             ----                       --------

                                                  
Scott D. Sheffield                      48              President

Timothy L. Dove                         44              Executive Vice President, Chief
                                                          Financial Officer and Director

Dennis E. Fagerstone                    51              Executive Vice President and Director

Mark L. Withrow                         53              Executive Vice President, General
                                                          Counsel and Director

Danny Kellum                            46              Executive Vice President - Domestic
                                                          Operations and Director

Rich Dealy                              34              Vice President and Chief Accounting
                                                          Officer


      Scott D. Sheffield. Mr. Sheffield is a graduate of The University of Texas
with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.




                                       21
   1608


      Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

      Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School of
Mines with a B.S. in Petroleum Engineering, became an Executive Vice President
of Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. He served as Executive Vice President and Chief
Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until August 1997.
From October 1996 to February 1997, Mr. Fagerstone served as Senior Vice
President and Chief Operating Officer of Mesa and from May 1991 to October 1996,
he served as Vice President - Exploration and Production of Mesa. From June 1988
to May 1991, Mr. Fagerstone served as Vice President - Operations of Mesa.

      Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

      Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

      Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University with
a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.




                                       22
   1609



ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by Pioneer USA, the managing general partner. The
Partnership participates in oil and gas activities through an income tax
partnership (the "Program") pursuant to the Program agreement. Under the Program
agreement, Pioneer USA pays approximately 10% of the Program's acquisition,
drilling and completion costs and approximately 15% during the first three years
and approximately 20% after three years of its operating and general and
administrative expenses. In return, they are allocated approximately 15% during
the first three years and approximately 20% after three years of the Program's
revenues.

The Partnership does not directly pay any salaries of the executive officers or
employees of Pioneer USA, but does pay a portion of Pioneer USA's general and
administrative expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 27 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:





                                       23
   1610




                                                        2000          1999           1998
                                                   ------------- -------------  -------------
                                                                       
    Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                $ 210,287     $ 203,686      $199,461

    Reimbursement of general and administrative
      expenses                                     $  44,112     $  25,818      $ 20,639


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.



                                       24
   1611


                                     PART IV

ITEM 14.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)   1.   Financial statements

           The following are filed as part of this Report:

               Independent Auditors' Report

               Balance sheets as of December 31, 2000 and 1999

               Statements of operations for the years ended December 31, 2000,
                 1999 and 1998

               Statements of partners' capital for the years ended December 31,
                 2000, 1999 and 1998

               Statements of cash flows for the years ended December 31, 2000,
                 1999 and 1998

               Notes to financial statements

      2.   Financial statement schedules

           All financial statement schedules have been omitted since the
           required information is in the financial statements or notes thereto,
           or is not applicable nor required.

(b)   Reports on Form 8-K

None.

(c)   Exhibits

      The exhibits listed on the accompanying index to exhibits are filed or
      incorporated by reference as part of this Report.



                                       25
   1612


                               S I G N A T U R E S

      Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                          PARKER & PARSLEY 90-C, L.P.

Dated: March 26, 2001               By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                -------------------------------
                                                Scott D. Sheffield, President

      Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                       
/s/ Scott D. Sheffield               President of Pioneer USA                 March 26, 2001
-------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                  Executive Vice President, Chief          March 26, 2001
-------------------------------      Financial Officer and Director of
Timothy L. Dove                      Pioneer USA


/s/ Dennis E. Fagerstone             Executive Vice President and             March 26, 2001
-------------------------------      Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                  Executive Vice President, General        March 26, 2001
-------------------------------      Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                     Executive Vice President - Domestic      March 26, 2001
-------------------------------      Operations and Director of Pioneer
Danny Kellum                         USA


/s/ Rich Dealy                       Vice President and Chief Accounting      March 26, 2001
-------------------------------      Officer of Pioneer USA
Rich Dealy




                                       26
   1613


                                     PARKER & PARSLEY 90-C, L.P.

                                INDEX TO EXHIBITS

      The following documents are incorporated by reference in response to Item
14(c):



     Exhibit No.                         Description                              Page
     -----------                         -----------                              ----

                                                                           
       3(a)               Form of Agreement of Limited Partnership                  -
                          of Parker & Parsley 90-C, L.P. incorporated
                          by reference to Exhibit A of the Post-Effective
                          Amendment No. 1 of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(b)               Form of Limited Partner Subscription Agreement            -
                          incorporated by reference to Exhibit C of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Form of General Partner Subscription Agreement            -
                          incorporated by reference to Exhibit D of the
                          Post-Effective Amendment No. 1 of the
                          Partnership's Registration Statement on Form
                          S-1 (Registration No. 33-26097)

       4(b)               Power of Attorney incorporated by reference to            -
                          Exhibit B of Amendment No. 1 of the Partnership's
                          Registration Statement on Form S-1
                          (Registration No. 33-26097)

       4(c)               Specimen Certificate of Limited Partnership               -
                          Interest incorporated by reference to Exhibit 4c
                          of the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)

      10(b)               Form of Development Drilling Program                      -
                          Agreement incorporated by reference to Exhibit
                          B of the Post-Effective Amendment No. 1 of
                          the Partnership's Registration Statement on
                          Form S-1 (Registration No. 33-26097)






                                       27
   1614





                           PARKER & PARSLEY 90-C, L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  311,387   $1,474,499   $  864,722   $  692,090   $1,063,396   $1,346,937
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  298,622   $  127,213   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  147,498   $  818,778   $  220,855   $ (416,064)  $  168,261   $  577,803
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
      Managing general
         partner                   $          $    1,475   $    8,188   $    2,209   $   (4,161)  $    1,683   $    5,778
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

      Limited partners             $          $  146,023   $  810,590   $  218,646   $ (411,903)  $  166,578   $  572,025
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net income
    (loss) per limited
    partnership interest           $          $    12.06   $    66.95   $    18.06   $   (34.02)  $    13.76   $    47.25
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    13.62   $    65.37   $    18.04   $    17.30   $    47.53   $    51.98
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,605,556   $1,636,242   $1,621,156   $1,617,114   $2,261,689   $2,664,141
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1615
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED      , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS      , 2001

                                   ----------


    This document contains important information specific to Parker & Parsley
Private Investment 90, L.P., and supplements the proxy statement/prospectus
dated       , 2001, of Pioneer Natural Resources Company and Pioneer Natural
Resources USA, Inc., by which Pioneer USA is soliciting proxies to be voted at
a special meeting of limited partners of the partnership. The purpose of the
special meeting is for you to vote upon the merger of the partnership with and
into Pioneer USA that, if completed, will result in your receiving common stock
of Pioneer Natural Resources Company for your partnership interests.


    This document contains the following information concerning Parker & Parsley
Private Investment 90, L.P.:

    o    A table containing:

         --       the aggregate initial investment by the limited partners


         --       the aggregate historical limited partner distributions through
                  July 31, 2001

         --       the merger value attributable to partnership interests of
                  limited partners, excluding Pioneer USA

         --       the merger value per $1,000 limited partner investment

         --       the merger value per $1,000 limited partner investment as a
                  multiple of distributions for the past four quarterly
                  distributions including the distribution in July 2001


         --       the book value per $1,000 limited partner investment as of
                  March 31, 2001 and as of December 31, 2000


         --       the going concern value per $1,000 limited partner investment

         --       the liquidation value per $1,000 limited partner investment


         --       the ordinary tax loss per $1,000 limited partner investment in
                  year of initial investment


    o    Information about:

         --       the legal opinion for the limited partners

         --       the term of the partnership

    o    The partnership's financial statements, including management's
         discussion and analysis of financial condition and results of
         operations, for the three months ended March 31, 2001

    o    The partnership's financial statements, including management's
         discussion and analysis of financial condition and results of
         operations, for the year ended December 31, 2000


    o    Selected historical financial data for the partnership for the three
         months ended March 31, 2001 and 2000 and the five years ended December
         31, 2000

                                      -1-


   1616
                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                            
Aggregate Initial Investment by the Limited Partners(a)                                        $  10,970

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                    $   9,030

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer      $   3,386
USA(a), (b)

Merger Value per $1,000 Limited Partner Investment(b),(c)                                      $  310.40

Merger Value per $1,000 Limited Partner Investment as a Multiple of                                 3.31 times
Distributions for the past four quarterly distributions including the
distribution in July 2001(b),(c)

Book Value per $1,000 Limited Partner Investment:

     --   as of March 31, 2001(c)                                                              $  151.57

     --   as of December 31, 2000(c)                                                           $  156.96

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                              $  290.55

Liquidation Value per $1,000 Limited Partner Investment(c),(e)                                 $  301.15

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial                     $     165
Investment(c),(f)


----------
(a) Stated in thousands.


(b) The merger value for the partnership is equal to the sum of the present
    value of estimated future net revenues from the partnership's estimated oil
    and gas reserves and its net working capital, in each case as of March 31,
    2001, less its pro rata share, based on its reserve value, of the estimated
    expenses and fees of the mergers of all of the partnerships and less the
    cash distribution on or about July 9, 2001, by the partnership to its
    partners.

(c) Interests in some partnerships were sold in units at prices other than
    $1,000. We have presented this information based on a $1,000 initial
    investment for ease of use and comparison among partnerships. You should not
    assume that the amount shown per $1,000 investment is the same as the value
    or amount attributable to a single unit investment.

(d) The going concern value for the partnership is based upon: (1) the sum of
    (A) the estimated net cash flow from the sale of the partnership's reserves
    during a 10-year operating period and (B) the estimated residual value from
    the sale of the partnership's remaining reserves at the end of the operating
    period, in each case using the same pricing and discount rate as in the
    merger value calculation, less (2) partnership level general and
    administrative expenses.

(e) The liquidation value for the partnership is based upon the sale of the
    partnership's reserves at the reserve value, less liquidation expenses which
    are estimated to be the sum of (1) the partnership's pro rata share of the
    merger expenses and fees described in footnote (b) above and (2) 3% of the
    partnership's reserve value. The liquidation expenses represent estimated
    costs to retain an investment banker or broker to sell the assets of the
    partnership and the legal and other closing costs associated with such
    transaction, including the wind-down costs of the partnership.

(f) Your ability to use your distributive share of the partnership's loss to
    offset your other income may have been subject to certain limitations at
    your level as a partner, and you may therefore wish to consult your tax
    advisor to determine the additional value, if any, actually realized by you
    in your particular circumstances.

          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

    The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

    The term of the partnership is until December 31, 2040, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                       -2-


   1617

                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   1618



                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS





                                                   March 31,     December 31,
                                                     2001            2000
                                                 ------------    ------------
                                                 (Unaudited)
                                                           
                 ASSETS

Current assets:
  Cash                                           $    160,171    $    168,054
  Accounts receivable - oil and gas sales             181,731         197,750
                                                 ------------    ------------
        Total current assets                          341,902         365,804
                                                 ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              8,465,268       8,464,366
Accumulated depletion                              (7,095,922)     (7,073,249)
                                                 ------------    ------------
        Net oil and gas properties                  1,369,346       1,391,117
                                                 ------------    ------------
                                                 $  1,711,248    $  1,756,921
                                                 ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $     27,519    $     13,453

Partners' capital:
  Managing general partner                             21,051          21,649
  Limited partners (274.25 interests)               1,662,678       1,721,819
                                                 ------------    ------------
                                                    1,683,729       1,743,468
                                                 ------------    ------------
                                                 $  1,711,248    $  1,756,921
                                                 ============    ============



The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   1619

                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  396,909   $  337,608
  Interest                                         2,920        2,426
                                              ----------   ----------
                                                 399,829      340,034
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                         120,499      112,552
  General and administrative                      11,777       10,128
  Depletion                                       22,673       31,828
                                              ----------   ----------
                                                 154,949      154,508
                                              ----------   ----------
Net income                                    $  244,880   $  185,526
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $    2,449   $    1,855
                                              ==========   ==========
  Limited partners                            $  242,431   $  183,671
                                              ==========   ==========
Net income per limited partnership interest   $   883.98   $   669.72
                                              ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   1620

                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                               Managing
                                general        Limited
                                partner        partners          Total
                             ------------    ------------    ------------
                                                    
Balance at January 1, 2001   $     21,649    $  1,721,819    $  1,743,468

    Distributions                  (3,047)       (301,572)       (304,619)

    Net income                      2,449         242,431         244,880
                             ------------    ------------    ------------

Balance at March 31, 2001    $     21,051    $  1,662,678    $  1,683,729
                             ============    ============    ============




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   1621

                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                       Three months ended
                                                            March 31,
                                                     ------------------------
                                                        2001          2000
                                                     ----------    ----------
                                                             
Cash flows from operating activities:
  Net income                                         $  244,880    $  185,526
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                         22,673        31,828
  Changes in assets and liabilities:
       Accounts receivable                               16,019       (22,065)
       Accounts payable                                  14,066           632
                                                     ----------    ----------
         Net cash provided by operating activities      297,638       195,921
                                                     ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                      (902)       (2,428)

Cash flows used in financing activities:
  Cash distributions to partners                       (304,619)     (166,714)
                                                     ----------    ----------
Net increase (decrease) in cash                          (7,883)       26,779
Cash at beginning of period                             168,054       174,341
                                                     ----------    ----------
Cash at end of period                                $  160,171    $  201,120
                                                     ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   1622

                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.  Organization and nature of operations

Parker & Parsley Private Investment 90, L.P. (the "Partnership") was organized
in 1990 as a general partnership under the laws of the State of Texas and was
converted to a Delaware limited partnership in 1991.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 18% to $396,909 for the three
months ended March 31, 2001 as compared to $337,608 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decline in production. For the three months ended March 31, 2001, 9,409
barrels of oil, 2,026 barrels of natural gas liquids ("NGLs") and 14,913 mcf of
gas were sold, or 13,921 barrel of oil equivalents ("BOEs"). For the three



                                        6
   1623

months ended March 31, 2000, 9,901 barrels of oil, 3,207 barrels of NGLs and
12,754 mcf of gas were sold, or 15,234 BOEs.

The average price received per barrel of oil increased $1.00, or 4%, from $27.27
for the three months ended March 31, 2000 to $28.27 for the same period in 2001.
The average price received per barrel of NGLs increased $5.75, or 41%, from
$14.06 for the three months ended March 31, 2000 to $19.81 for the same period
in 2001. The average price received per mcf of gas increased 244% from $1.77
during the three months ended March 31, 2000 to $6.09 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $154,949 for the three months ended March
31, 2001 as compared to $154,508 for the same period in 2000, an increase of
$441. This increase was primarily due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $120,499 for the three months ended March 31, 2001 and
$112,552 for the same period in 2000 resulting in a $7,947 increase, or 7%. The
increase was primarily due to higher production taxes associated with higher oil
and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 16% from $10,128 for the three months ended March 31, 2000 to $11,777
for the same period in 2001 primarily due to an increase in the accrual for tax
preparation fees

Depletion was $22,673 for the three months ended March 31, 2001 as compared to
$31,828 for the same period in 2000, a decrease of $9,155, or 29%. This decrease
was due to positive revisions to proved reserves during the three months ended
March 31, 2001 as a result of higher commodity prices and a decline in oil
production of 492 barrels for the three months ended March 31, 2001 as compared
to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $101,717 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $59,795 and a
reduction in working capital of $51,518, offset by increases in production costs
of $7,947 and G&A expenses of $1,649. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an



                                        7
   1624

additional $83,969 to oil and gas receipts, offset by $24,174 resulting from the
decline in production during 2001 as compared to the same period in 2000. The
increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to an increase
in the accrual for tax preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2001 and 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $304,619, of which $3,047 was distributed to the managing general partner
and $301,572 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $166,714, of which $1,667 was
distributed to the managing general partner and $165,047 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results
     of Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   1625


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999




   1626



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley Private Investment 90, L.P.
 (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley Private Investment 90,
L.P. as of December 31, 2000 and 1999, and the related statements of operations,
partners' capital and cash flows for each of the three years in the period ended
December 31, 2000. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley Private
Investment 90, L.P. as of December 31, 2000 and 1999, and the results of its
operations and its cash flows for each of the three years in the period ended
December 31, 2000, in conformity with accounting principles generally accepted
in the United States.



                                             Ernst & Young LLP


Dallas, Texas
March 9, 2001



                                       2
   1627


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                            2000               1999
                                                         -----------        -----------
                                                                      
               ASSETS
               ------

Current assets:
  Cash                                                   $   168,054        $   174,341
  Accounts receivable - oil and gas sales                    197,750            117,410
                                                         -----------        -----------

          Total current assets                               365,804            291,751
                                                         -----------        -----------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                     8,464,366          8,438,988
Accumulated depletion                                     (7,073,249)        (6,916,963)
                                                         -----------        -----------

          Net oil and gas properties                       1,391,117          1,522,025
                                                         -----------        -----------

                                                         $ 1,756,921        $ 1,813,776
                                                         ===========        ===========

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                           $    13,453        $    24,649

Partners' capital:
  Managing general partner                                    21,649             22,105
  Limited partners (274.25 interests)                      1,721,819          1,767,022
                                                         -----------        -----------

                                                           1,743,468          1,789,127
                                                         -----------        -----------

                                                         $ 1,756,921        $ 1,813,776
                                                         ===========        ===========





   The accompanying notes are an integral part of these financial statements.


                                       3
   1628


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                                 2000              1999               1998
                                                              -----------       -----------       -----------
                                                                                         
Revenues:

  Oil and gas                                                 $ 1,508,541       $   776,849       $   648,378
  Interest                                                         14,348             7,221             9,116
  Gain on disposition of assets                                     2,385                 -                 -
                                                              -----------       -----------       -----------

                                                                1,525,274           784,070           657,494
                                                              -----------       -----------       -----------

Costs and expenses:
  Oil and gas production                                          502,676           379,923           481,924
  General and administrative                                       41,729            29,997            20,196
  Impairment of oil and gas properties                             49,757                 -           373,422
  Depletion                                                       106,529           143,268           224,780
                                                              -----------       -----------       -----------

                                                                  700,691           553,188         1,100,322
                                                              -----------       -----------       -----------

Net income (loss)                                             $   824,583       $   230,882       $  (442,828)
                                                              ===========       ===========       ===========

Allocation of net income (loss):
  Managing general partner                                    $     8,246       $     2,309       $    (4,428)
                                                              ===========       ===========       ===========

  Limited partners                                            $   816,337       $   228,573       $  (438,400)
                                                              ===========       ===========       ===========

Net income (loss) per limited partnership interest            $  2,976.62       $    833.45       $ (1,598.54)
                                                              ===========       ===========       ===========





   The accompanying notes are an integral part of these financial statements.


                                       4
   1629


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                                    Managing
                                                     general           Limited
                                                     partner           partners             Total
                                                   -----------        -----------        -----------
                                                                                
Partners' capital at January 1, 1998               $    29,418        $ 2,491,033        $ 2,520,451

   Distributions                                        (2,635)          (260,830)          (263,465)

   Net loss                                             (4,428)          (438,400)          (442,828)
                                                   -----------        -----------        -----------

Partners' capital at December 31, 1998                  22,355          1,791,803          1,814,158

   Distributions                                        (2,559)          (253,354)          (255,913)

   Net income                                            2,309            228,573            230,882
                                                   -----------        -----------        -----------

Partners' capital at December 31, 1999                  22,105          1,767,022          1,789,127

   Distributions                                        (8,702)          (861,540)          (870,242)

   Net income                                            8,246            816,337            824,583
                                                   -----------        -----------        -----------

Partners' capital at December 31, 2000             $    21,649        $ 1,721,819        $ 1,743,468
                                                   ===========        ===========        ===========





   The accompanying notes are an integral part of these financial statements.


                                       5
   1630


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                                 2000            1999              1998
                                                              ---------        ---------        ---------
                                                                                       

Cash flows from operating activities:
  Net income (loss)                                           $ 824,583        $ 230,882        $(442,828)
  Adjustments to reconcile net income (loss)to
     net cash provided by operating activities:
       Impairment of oil and gas properties                      49,757                -          373,422
       Depletion                                                106,529          143,268          224,780
       Gain on disposition of assets                             (2,385)               -                -
  Changes in assets and liabilities:
       Accounts receivable                                      (80,340)         (50,462)          48,403
       Accounts payable                                         (11,196)           4,017           (8,903)
                                                              ---------        ---------        ---------

          Net cash provided by operating activities             886,948          327,705          194,874
                                                              ---------        ---------        ---------

Cash flows from investing activities:
  Additions to oil and gas properties                           (25,378)         (14,048)         (11,793)
  Proceeds from asset dispositions                                2,385            2,124           11,927
                                                              ---------        ---------        ---------

          Net cash provided by (used in) investing
            activities                                          (22,993)         (11,924)             134
                                                              ---------        ---------        ---------

Cash flows used in financing activities:
  Cash distributions to partners                               (870,242)        (255,913)        (263,465)
                                                              ---------        ---------        ---------

Net increase (decrease) in cash                                  (6,287)          59,868          (68,457)
Cash at beginning of year                                       174,341          114,473          182,930
                                                              ---------        ---------        ---------

Cash at end of year                                           $ 168,054        $ 174,341        $ 114,473
                                                              =========        =========        =========





   The accompanying notes are an integral part of these financial statements.



                                       6
   1631


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.         ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley Private Investment 90, L.P. (the "Partnership") was
organized in 1990 as a general partnership under the laws of the State of Texas
and was converted to a Delaware limited partnership in 1991. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.         SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.



                                       7
   1632


        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non- partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally discounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.         IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $49,757 and $373,422
related to its proved oil and gas properties during 2000 and 1998, respectively.


                                       8
   1633


NOTE 4.         INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $139,996 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                2000             1999            1998
                                                              ---------        ---------       ---------
                                                                                      

Net income (loss) per statements of operations                $ 824,583        $ 230,882       $(442,828)
Depletion and depreciation for tax reporting purposes
   less than amounts for financial reporting purposes            93,056          131,771         204,399
Impairment of oil and gas properties for financial
   reporting purposes                                            49,757                -         373,422
Other, net                                                       (1,853)             432          13,939
                                                              ---------        ---------       ---------

   Net income per Federal income tax returns                  $ 965,543        $ 363,085       $ 148,932
                                                              =========        =========       =========


NOTE 5.         OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                           2000             1999              1998
                                        ----------        ---------        ----------
                                                                  

Development costs                       $   25,378        $  14,048        $   11,793
                                        ==========        =========        ==========


        Capitalized oil and gas properties consist of the following:



                                                      2000                1999
                                                   -----------        -----------
                                                                

Proved properties:
   Property acquisition costs                      $    98,110        $    98,110
   Completed wells and equipment                     8,366,256          8,340,878
                                                   -----------        -----------

                                                     8,464,366          8,438,988
Accumulated depletion                               (7,073,249)        (6,916,963)
                                                   -----------        -----------

            Net oil and gas properties             $ 1,391,117        $ 1,522,025
                                                   ===========        ===========




                                       9
   1634


NOTE 6.         RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                       2000            1999             1998
                                                     ---------       ---------       ---------
                                                                            

Payment of lease operating and supervision
  charges in accordance with standard industry
  operating agreements                               $ 186,568       $ 174,796       $ 187,435

Reimbursement of general and administrative
  expenses                                           $  37,554       $  23,205       $  16,483


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 90 Private Conv., L.P. ("EMPL") and the Partnership are parties to
the Program agreement. EMPL is a limited partnership organized for the benefit
of certain employees of Pioneer USA. EMPL was merged with Pioneer USA on
December 28, 2000.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                           Pioneer USA (1)         Partnership
                                                                           ---------------       ---------------
                                                                                           
Revenues:
   Proceeds from disposition of depreciable and
     depletable properties -
        First three years                                                     14.141414%          85.858586%
        After three years                                                     19.191919%          80.808081%
   All other revenues -
        First three years                                                     14.141414%          85.858586%
        After three years                                                     19.191919%          80.808081%
Costs and expenses:
   Lease acquisition costs, drilling and completion costs                      9.090909%          90.909091%
   Operating costs, reporting and legal expenses and
     general and administrative expenses -
        First three years                                                     14.141414%          85.858586%
        After three years                                                     19.191919%          80.808081%


(1)   Excludes Pioneer USA's 1% general partner ownership which is allocated at
      the Partnership level.

NOTE 7.         OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.



                                                   Oil and NGLs         Gas
                                                      (bbls)           (mcf)
                                                   ------------      ---------
                                                               

Net proved reserves at January 1, 1998                745,340          883,417
Revisions                                            (342,345)        (365,103)
Production                                            (49,468)         (54,218)
                                                    ---------        ---------

Net proved reserves at December 31, 1998              353,527          464,096
Revisions                                             394,885          538,864
Production                                            (46,335)         (47,331)
                                                    ---------        ---------

Net proved reserves at December 31, 1999              702,077          955,629
Revisions                                             172,617          (96,553)
Production                                            (52,913)         (49,484)
                                                    ---------        ---------

Net proved reserves at December 31, 2000              821,781          809,592
                                                    =========        =========




                                       10
   1635


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.49 per barrel of NGLs and $7.81 per mcf of gas,
discounted at 10% was approximately $5,749,000 and undiscounted was $12,495,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.




                                                                        For the years ended December 31,
                                                                  -------------------------------------------
                                                                     2000            1999              1998
                                                                  ---------        ---------        ---------
                                                                                (in thousands)
                                                                                           

Oil and gas producing activities:
   Future cash inflows                                            $  25,174        $  17,513        $   3,860
   Future production costs                                          (12,679)          (9,819)          (3,004)
                                                                  ---------        ---------        ---------

                                                                     12,495            7,694              856
   10% annual discount factor                                        (6,746)          (3,770)            (271)
                                                                  ---------        ---------        ---------

   Standardized measure of discounted future net cash flows       $   5,749        $   3,924        $     585
                                                                  =========        =========        =========




                                       11
   1636




                                                            For the years ended December 31,
                                                       ----------------------------------------
                                                         2000            1999            1998
                                                       --------        --------        --------
                                                                    (in thousands)
                                                                              

Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs           $ (1,006)       $   (397)       $   (166)
  Net changes in prices and production costs              1,905           2,019          (1,974)
  Revisions of previous quantity estimates                1,043           2,961            (437)
  Accretion of discount                                     392              58             299
  Changes in production rates, timing and other            (509)         (1,302)           (128)
                                                       --------        --------        --------

  Change in present value of future net revenues          1,825           3,339          (2,406)
                                                       --------        --------        --------

  Balance, beginning of year                              3,924             585           2,991
                                                       --------        --------        --------

  Balance, end of year                                 $  5,749        $  3,924        $    585
                                                       ========        ========        ========


NOTE 8.         MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:




                                                     2000            1999             1998
                                                   --------        --------         --------
                                                                           

Plains Marketing, L.P.                                71%              69%               -
Genesis Crude Oil, L.P.                                -                -               64%
Western Gas Resources, Inc.                            3%               4%              17%


        At December 31, 2000, the amount receivable from Plains Marketing, L.P.
was $93,082 which is included in the caption "Accounts receivable - oil and gas
sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.         PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being paid to
        the Partnership. Under the Partnership agreement, the managing general
        partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating and general and administrative
        expenses. The managing general partner is also responsible for 1% of
        guaranty and loan commitment fees. In return, it is allocated 1% of the
        Partnership's revenues.



                                       12
   1637


        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $10,970,000. The
        managing general partner is required to contribute amounts equal to 1%
        of initial Partnership capital less commission, organization and
        offering costs allocated to the limited partners and to contribute
        amounts necessary to pay costs and expenses allocated to it under the
        Partnership agreement to the extent that its share of revenues does not
        cover such costs.



                                       13

   1638


                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)


THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 94% to $1,508,541 for 2000 as
compared to $776,849 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 39,040 barrels
of oil, 13,873 barrels of natural gas liquids ("NGLs") and 49,484 mcf of gas
were sold, or 61,160 barrel of oil equivalents ("BOEs"). In 1999, 32,789 barrels
of oil, 13,546 barrels of NGLs and 47,331 mcf of gas were sold, or 54,224 BOEs.
Due to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.05, or 70%, from
$17.30 in 1999 to $29.35 in 2000. The average price received per barrel of NGLs
increased $6.36, or 67%, from $9.46 in 1999 to $15.82 in 2000. The average price
received per mcf of gas increased 69% from $1.72 in 1999 to $2.90 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $700,691 as compared to $553,188
in 1999, an increase of $147,503, or 27%. The increase was primarily due to
increases in the impairment of oil and gas properties, production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $502,676 in 2000 and $379,923 in 1999, resulting in a
$122,753 increase, or 32%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
39% from $29,997 in 1999 to $41,729 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $37,554 in 2000 and $23,205 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long- Lived Assets and for Long-Lived Assets
to be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $49,757 related to its oil and gas properties during 2000.

Depletion was $106,529 in 2000 as compared to $143,268 in 1999, representing a
decrease of $36,739, or 26%. This decrease was primarily due to a 148,753
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices, offset by an increase in oil production of 6,251 barrels for
the period ended December 31, 2000 compared to the same period in 1999.


   1639


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 20% to $776,849 from
$648,378 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 32,789 barrels of oil,
13,546 barrels of NGLs and 47,331 mcf of gas were sold, or 54,224 BOEs. In 1998,
35,555 barrels of oil, 13,913 barrels of NGLs and 54,218 mcf of gas were sold,
or 58,504 BOEs.

The average price received per barrel of oil increased $4.11, or 31%, from
$13.19 in 1998 to $17.30 in 1999. The average price received per barrel of NGLs
increased $2.69, or 40%, from $6.77 in 1998 to $9.46 in 1999. The average price
received per mcf of gas increased 10% from $1.57 in 1998 to $1.72 in 1999.

Total costs and expenses decreased in 1999 to $553,188 as compared to $1,100,322
in 1998, a decrease of $547,134, or 50%. The decrease was primarily due to
declines in the impairment of oil and gas properties, production costs and
depletion, offset by an increase in G&A.

Production costs were $379,923 in 1999 and $481,924 in 1998, resulting in a
$102,001 decrease, or 21%. The decrease was due to declines in well maintenance
costs and ad valorem taxes.

During this period, G&A increased 49% from $20,196 in 1998 to $29,997 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $23,205 in
1999 and $16,483 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized a non-cash SFAS 121 charge of $373,422 related to its
oil and gas properties during 1998.

Depletion was $143,268 in 1999 compared to $224,780 in 1998, representing a
decrease of $81,512, or 36%. This decrease was the result of an increase in
proved reserves of 266,736 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.



   1640


Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $559,243 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $738,819, offset by increases in production costs paid
of $122,753, G&A expenses paid of $11,732 and working capital of $45,091. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $543,958 to oil and gas receipts and
an increase of $194,861 resulting from the increase in production during 2000.
The increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and well maintenance costs incurred to
stimulate well production. The increase in G&A was primarily due to higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active properties.

Proceeds from asset dispositions of $2,385 and $2,124 recognized during 2000 and
1999, respectively, were due to equipment credits received on active properties.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $870,242, of which $8,702 was
distributed to the managing general partner and $861,540 to the limited
partners. In 1999, cash distributions to the partners were $255,913, of which
$2,559 was distributed to the managing general partner and $253,354 to the
limited partners.





   1641





                  PARKER & PARSLEY PRIVATE INVESTMENT 90, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  337,608   $1,508,541   $  776,849   $  648,378   $1,043,119   $1,237,784
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   49,757   $       --   $  373,422   $       --   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  185,526   $  824,583   $  230,882   $ (442,828)  $  403,823   $  571,998
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $    1,855   $    8,246   $    2,309   $   (4,428)  $    4,038   $    5,720
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $  183,671   $  816,337   $  228,573   $ (438,400)  $  399,785   $  566,278
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   669.72   $ 2,976.62   $   833.45   $(1,598.54)  $ 1,457.74   $ 2,064.82
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   601.81   $ 3,141.44   $   923.81   $   951.07   $ 2,289.37   $ 2,184.00
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $1,833,220   $1,756,921   $1,813,776   $1,834,790   $2,549,986   $2,769,711
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========





   1642
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

            PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.,
                         A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
90 Spraberry Private Development, L.P., and supplements the proxy
statement/prospectus dated      , 2001, of Pioneer Natural Resources Company and
Pioneer Natural Resources USA, Inc., by which Pioneer USA is soliciting proxies
to be voted at a special meeting of limited partners of the partnership. The
purpose of the special meeting is for you to vote upon the merger of the
partnership with and into Pioneer USA that, if completed, will result in your
receiving common stock of Pioneer Natural Resources Company for your partnership
interests.


     This document contains the following information concerning Parker &
Parsley 90 Spraberry Private Development, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the three months ended March 31, 2001

     o    The partnership's financial statements, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000


     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-

   1643
             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $   5,200

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   3,954

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   1,500
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  288.51

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          4.07 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $  143.56

          --  as of December 31, 2000 (c)                                                     $  141.88

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  269.40

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  279.85

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     168
(c), (f)


----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2040, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-
   1644

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.

                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS

                                 March 31, 2001


   1645



             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS





                                                   March 31,     December 31,
                                                     2001            2000
                                                 ------------    ------------
                                                 (Unaudited)
                                                           
                 ASSETS

Current assets:
  Cash                                           $     63,837    $     47,337
  Accounts receivable - oil and gas sales              92,965          91,915
                                                 ------------    ------------
        Total current assets                          156,802         139,252
                                                 ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method              3,666,171       3,666,171
Accumulated depletion                              (3,054,713)     (3,046,352)
                                                 ------------    ------------
        Net oil and gas properties                    611,458         619,819
                                                 ------------    ------------
                                                 $    768,260    $    759,071
                                                 ============    ============

LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                   $     12,899    $     12,584

Partners' capital:
  Managing general partner                              8,826           8,737
  Limited partners (130 interests)                    746,535         737,750
                                                 ------------    ------------
                                                      755,361         746,487
                                                 ------------    ------------
                                                 $    768,260    $    759,071
                                                 ============    ============




The financial information included as of March 31, 2001 has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        2
   1646

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  183,614   $  133,917
  Interest                                         1,073        1,133
                                              ----------   ----------
                                                 184,687      135,050
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                          53,740       58,485
  General and administrative                       6,374        4,365
  Depletion                                        8,361       13,382
                                              ----------   ----------
                                                  68,475       76,232
                                              ----------   ----------
Net income                                    $  116,212   $   58,818
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $    1,162   $      588
                                              ==========   ==========
  Limited partners                            $  115,050   $   58,230
                                              ==========   ==========
Net income per limited partnership interest   $   885.00   $   447.92
                                              ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3
   1647

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)





                              Managing
                               general      Limited
                               partner      partners        Total
                             ----------    ----------    ----------
                                                
Balance at January 1, 2001   $    8,737    $  737,750    $  746,487

    Distributions                (1,073)     (106,265)     (107,338)

    Net income                    1,162       115,050       116,212
                             ----------    ----------    ----------

Balance at March 31, 2001    $    8,826    $  746,535    $  755,361
                             ==========    ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        4
   1648

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                         Three months ended
                                                              March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
  Net income                                           $  116,212    $   58,818
  Adjustments to reconcile net income to net
    cash provided by operating activities:
       Depletion                                            8,361        13,382
  Changes in assets and liabilities:
       Accounts receivable                                 (1,050)       (3,777)
       Accounts payable                                       315        10,468
                                                       ----------    ----------
           Net cash provided by operating activities      123,838        78,891
                                                       ----------    ----------
Cash flows used in investing activities:
  Additions to oil and gas properties                          --        (1,181)

Cash flows used in financing activities:
  Cash distributions to partners                         (107,338)      (87,613)
                                                       ----------    ----------
Net increase (decrease) in cash                            16,500        (9,903)
Cash at beginning of period                                47,337        84,843
                                                       ----------    ----------
Cash at end of period                                  $   63,837    $   74,940
                                                       ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        5
   1649

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)


Note 1.  Organization and nature of operations

Parker & Parsley 90 Spraberry Private Development, L.P. (the "Partnership") was
organized in 1990 as a general partnership under the laws of the State of Texas
and was converted to a Delaware limited partnership in 1991.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.  Basis of presentation

In the opinion of management, the unaudited financial statements of Parker &
Parsley 90 Spraberry Private Development, L.P. (the "Partnership") as of March
31, 2001 include all adjustments and accruals consisting only of normal
recurring accrual adjustments which are necessary for a fair presentation of the
results for the interim period. These interim results are not necessarily
indicative of results for a full year.

Certain information and footnote disclosure normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in these interim financial statements. The
financial statements should be read in conjunction with the financial statements
and the notes thereto contained in the Partnership's report for the year ended
December 31, 2000, a copy of which is available upon request by writing to Rich
Dealy, Vice President and Chief Accounting Officer, 5205 North O'Connor
Boulevard, 1400 Williams Square West, Irving, Texas 75039-3746.

Management's Discussion and Analysis of Financial Condition and
     Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 37% to $183,614 for the three
months ended March 31, 2001 as compared to $133,917 for the same period in 2000.
The increase in revenues resulted from higher average prices received and an
increase in production. For the three months ended March 31, 2001, 4,046 barrels
of oil, 1,147 barrels of natural gas liquids ("NGLs") and 8,177 mcf of gas were



                                        6
   1650

sold, or 6,556 barrel of oil equivalents ("BOEs"). For the three months ended
March 31, 2000, 4,139 barrels of oil, 1,076 barrels of NGLs and 3,949 mcf of gas
were sold, or 5,873 BOEs.

The average price received per barrel of oil increased $.97, or 4%, from $26.99
for the three months ended March 31, 2000 to $27.96 for the same period in 2001.
The average price received per barrel of NGLs increased $4.80, or 33%, from
$14.49 for the three months ended March 31, 2000 to $19.29 for the same period
in 2001. The average price received per mcf of gas increased 252% from $1.68
during the three months ended March 31, 2000 to $5.91 for the same period in
2001. The market price for oil and gas has been extremely volatile in the past
decade, and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received during the three
months ended March 31, 2001.

Costs and Expenses:

Total costs and expenses decreased to $68,475 for the three months ended March
31, 2001 as compared to $76,232 for the same period in 2000, a decrease of
$7,757, or 10%. This decrease was primarily due to declines in depletion and
production costs, offset by an increase in general and administrative expenses
("G&A").

Production costs were $53,740 for the three months ended March 31, 2001 and
$58,485 for the same period in 2000 resulting in a $4,745 decrease, or 8%. The
decrease was due to lower well maintenance costs, offset by higher production
taxes associated with higher oil and gas prices.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 46% from $4,365 for the three months ended March 31, 2000 to $6,374
for the same period in 2001, primarily due to a higher percentage of the
managing general partner's G&A being allocated (limited to 3% of oil and gas
revenues) as a result of increased oil and gas revenues and an increase in the
accrual for tax preparation fees.

Depletion was $8,361 for the three months ended March 31, 2001 as compared to
$13,382 for the same period in 2000, a decrease of $5,021, or 38%. This decrease
was primarily due to positive revisions to proved reserves during the three
months ended March 31, 2001 as a result of higher commodity prices and a decline
in oil production of 93 barrels for the period ended March 31, 2001 as compared
to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $44,947 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. This
increase was due to an increase in oil and gas sales receipts of $49,637 and a



                                        7
   1651

decrease in production costs of $4,745, offset by an increase in G&A expenses of
$2,009 and working capital of $7,426. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $25,873 to oil and gas receipts and $23,764 resulting from an
increase in production during 2001 as compared to the same period in 2000. The
decrease in production costs was due to lower well maintenance costs, offset by
higher production taxes associated with higher oil and gas prices. The increase
in G&A was primarily due to a higher percentage of the managing general
partner's G&A being allocated (limited to 3% of oil and gas revenues) as a
result of increased oil and gas revenues and an increase in the accrual of tax
preparation fees.

Net Cash Used in Investing Activities

For the three months ended March 31, 2000, the Partnership's investing
activities included expenditures related to equipment upgrades on active oil and
gas properties.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $107,338, of which $1,073 was distributed to the managing general partner
and $106,265 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $87,613, of which $876 was distributed
to the managing general partner and $86,737 to the limited partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, the majority approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Management's Discussion and Analysis of Financial Condition and Results of
     Operations" contains forward looking statements that involve risks and
     uncertainties. Accordingly, no assurances can be given that the actual
     events and results will not be materially different than the anticipated
     results described in the forward looking statements.



                                        8
   1652
             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)


                              FINANCIAL STATEMENTS
                                      WITH
                          INDEPENDENT AUDITORS' REPORT


                           December 31, 2000 and 1999

   1653

                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 90 Spraberry Private Development, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 90 Spraberry Private
Development, L.P. as of December 31, 2000 and 1999, and the related statements
of operations, partners' capital and cash flows for each of the three years in
the period ended December 31, 2000. These financial statements are the
responsibility of the Partnership's management. Our responsibility is to express
an opinion on these financial statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 90 Spraberry
Private Development, L.P. as of December 31, 2000 and 1999, and the results of
its operations and its cash flows for each of the three years in the period
ended December 31, 2000, in conformity with accounting principles generally
accepted in the United States.



                                                   Ernst & Young LLP


Dallas, Texas
March 9, 2001


                                       2
   1654

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31




                                                       2000             1999
                                                   -----------      -----------
                                                              
              ASSETS
              ------

Current assets:
 Cash                                              $    47,337      $    84,843
 Accounts receivable - oil and gas sales                91,915           49,977
                                                   -----------      -----------

         Total current assets                          139,252          134,820
                                                   -----------      -----------

Oil and gas properties - at cost, based on the
 successful efforts accounting method                3,666,171        3,660,488
Accumulated depletion                               (3,046,352)      (3,005,158)
                                                   -----------      -----------

         Net oil and gas properties                    619,819          655,330
                                                   -----------      -----------

                                                   $   759,071      $   790,150
                                                   ===========      ===========


LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
 Accounts payable - affiliate                      $    12,584      $    81,557

Partners' capital:
 Managing general partner                                8,737            8,358
 Limited partners (130 interests)                      737,750          700,235
                                                   -----------      -----------

                                                       746,487          708,593
                                                   -----------      -----------

                                                   $   759,071      $   790,150
                                                   ===========      ===========



   The accompanying notes are an integral part of these financial statements.


                                       3
   1655

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31




                                                          2000          1999          1998
                                                       ---------     ---------     ----------
                                                                          
Revenues:
  Oil and gas                                          $ 638,385     $ 345,743     $  275,856
  Interest                                                 5,441         3,213          3,779
  Gain on disposition of assets                               --            --            213
                                                       ---------     ---------     ----------

                                                         643,826       348,956        279,848
                                                       ---------     ---------     ----------

Costs and expenses:
  Oil and gas production                                 235,823       177,422        184,952
  General and administrative                              20,910        14,767         10,935
  Impairment of oil and gas properties                        --            --         90,823
  Depletion                                               41,194        84,045        126,372
                                                       ---------     ---------     ----------

                                                         297,927       276,234        413,082
                                                       ---------     ---------     ----------

Net income (loss)                                      $ 345,899     $  72,722     $ (133,234)
                                                       =========     =========     ==========

Allocation of net income (loss):
  Managing general partner                             $   3,459     $     727     $   (1,332)
                                                       =========     =========     ==========

  Limited partners                                     $ 342,440     $  71,995     $ (131,902)
                                                       =========     =========     ==========

Net income (loss) per limited partnership interest     $2,634.15     $  553.81     $(1,014.63)
                                                       =========     =========     ==========



   The accompanying notes are an integral part of these financial statements.


                                       4
   1656

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL




                                             Managing
                                             general         Limited
                                             partner         partners           Total
                                           -----------      -----------      -----------

                                                                    
Partners' capital at January 1, 1998       $    11,813      $ 1,042,323      $ 1,054,136

  Distributions                                 (1,443)        (142,847)        (144,290)

  Net loss                                      (1,332)        (131,902)        (133,234)
                                           -----------      -----------      -----------

Partners' capital at December 31, 1998           9,038          767,574          776,612

  Distributions                                 (1,407)        (139,334)        (140,741)

  Net income                                       727           71,995           72,722
                                           -----------      -----------      -----------

Partners' capital at December 31, 1999           8,358          700,235          708,593

  Distributions                                 (3,080)        (304,925)        (308,005)

  Net income                                     3,459          342,440          345,899
                                           -----------      -----------      -----------

Partners' capital at December 31, 2000     $     8,737      $   737,750      $   746,487
                                           ===========      ===========      ===========



   The accompanying notes are an integral part of these financial statements.


                                       5
   1657

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                           2000           1999           1998
                                                        ---------      ---------      ---------
                                                                             
Cash flows from operating activities:
  Net income (loss)                                     $ 345,899      $  72,722      $(133,234)
     Adjustments to reconcile net income (loss) to
       net cash provided by operating activities:
          Impairment of oil and gas properties                 --             --         90,823
          Depletion                                        41,194         84,045        126,372
          Gain on disposition of assets                        --             --           (213)
     Changes in assets and liabilities:
       Accounts receivable                                (41,938)       (22,812)        21,422
       Accounts payable                                   (68,973)        39,718         31,154
                                                        ---------      ---------      ---------

          Net cash provided by operating activities       276,182        173,673        136,324
                                                        ---------      ---------      ---------

Cash flows from investing activities:
  Additions to oil and gas properties                      (5,683)        (2,042)        (7,821)
  Proceeds from asset dispositions                             --          3,269            213
                                                        ---------      ---------      ---------

          Net cash provided by (used in)
             investing activities                          (5,683)         1,227         (7,608)
                                                        ---------      ---------      ---------

Cash flows used in financing activities:
  Cash distributions to partners                         (308,005)      (140,741)      (144,290)
                                                        ---------      ---------      ---------

Net increase (decrease) in cash                           (37,506)        34,159        (15,574)
Cash at beginning of year                                  84,843         50,684         66,258
                                                        ---------      ---------      ---------

Cash at end of year                                     $  47,337      $  84,843      $  50,684
                                                        =========      =========      =========



   The accompanying notes are an integral part of these financial statements.


                                       6
   1658

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

        Parker & Parsley 90 Spraberry Private Development, L.P. (the
"Partnership") was organized in 1990 as a general partnership under the laws of
the State of Texas and was converted to a Delaware limited partnership in 1991.
The Partnership's managing general partner is Pioneer Natural Resources USA,
Inc. ("Pioneer USA").

        The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

        A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

        Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

        Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

        Use of estimates in the preparation of financial statements -
Preparation of the accompanying financial statements in conformity with
generally accepted accounting principles requires management to make estimates
and assumptions that affect the reported amounts of assets and liabilities and
disclosure of contingent assets and liabilities at the date of the financial
statements and the reported amounts of revenues and expenses during the
reporting periods. Actual results could differ from those estimates.

        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.


                                       7
   1659

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $90,823 related to its
proved oil and gas properties during 1998.


                                       8
   1660

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $43,760 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                            2000           1999          1998
                                                       ---------      ---------     ---------

                                                                           
Net income (loss) per statements of operations         $ 345,899      $  72,722     $(133,234)
Impairment of oil and gas properties for financial
  reporting purposes                                           -              -        90,823
Depletion, depreciation and amortization for tax
  reporting purposes less than amounts for
  financial reporting purposes                            36,539         79,135       110,651
Other, net                                               (76,555)        39,044        36,173
                                                       ---------      ---------     ---------

Net income per Federal income tax returns              $ 305,883      $ 190,901     $ 104,413
                                                       =========      =========     =========


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the net costs incurred, whether
capitalized or expensed, related to the Partnership's oil and gas producing
activities for the years ended December 31:



                         2000          1999       1998
                      ---------     ---------     ------

                                         
Development costs     $   5,683     $   2,042     $7,821
                      =========     =========     ======


        Capitalized oil and gas properties consist of the following:



                                        2000             1999
                                    -----------      -----------
                                               
Proved properties:
  Property acquisition costs        $    19,608      $    19,608
  Completed wells and equipment       3,646,563        3,640,880
                                    -----------      -----------

                                      3,666,171        3,660,488
Accumulated depletion                (3,046,352)      (3,005,158)
                                    -----------      -----------

  Net oil and gas properties        $   619,819      $   655,330
                                    ===========      ===========



                                       9
   1661

NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                          2000        1999        1998
                                                         -------     -------     -------
                                                                        
Payment of lease operating and supervision
  charges in accordance with standard industry
  operating agreements                                   $88,496     $85,512     $81,995

Reimbursement of general and administrative expenses     $18,935     $11,455     $ 9,241


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 90 Spraberry Private Conv., L.P. ("EMPL") and the Partnership are
parties to the Program agreement. EMPL is a limited partnership organized for
the benefit of certain employees of Pioneer USA. EMPL was merged with Pioneer
USA on December 28, 2000.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                             Pioneer USA (1)   Partnership
                                                             ---------------   -----------
                                                                         
Revenues:
  Proceeds from disposition of depreciable and
    depletable properties -
      First three years                                         14.141414%      85.858586%
      After three years                                         19.191919%      80.808081%
  All other revenues -
      First three years                                         14.141414%      85.858586%
      After three years                                         19.191919%      80.808081%
Costs and expenses:
  Lease acquisition costs, drilling and completion costs         9.090909%      90.909091%
  Operating costs, reporting and legal expenses and
    general and administrative expenses -
      First three years                                         14.141414%      85.858586%
      After three years                                         19.191919%      80.808081%


    (1) Excludes Pioneer USA's 1% general partner ownership which is allocated
        at the Partnership level.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.


                                       10
   1662



                                              Oil and NGLs          Gas
                                                 (bbls)            (mcf)
                                              ------------       --------

                                                           
Net proved reserves at January 1, 1998           270,590          306,642
Revisions                                       (126,717)        (142,535)
Production                                       (20,835)         (24,095)
                                                --------         --------

Net proved reserves at December 31, 1998         123,038          140,012
Revisions                                        214,995          265,098
Production                                       (20,688)         (19,579)
                                                --------         --------

Net proved reserves at December 31, 1999         317,345          385,531
Revisions                                        122,969           18,001
Production                                       (22,593)         (22,121)
                                                --------         --------

Net proved reserves at December 31, 2000         417,721          381,411
                                                ========         ========


        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.12 per barrel of NGLs and $7.64 per mcf of gas,
discounted at 10% was approximately $2,575,000 and undiscounted was $5,966,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

        The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

        Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.



                                                                        For the years ended December 31,
                                                                  ------------------------------------------
                                                                    2000             1999             1998
                                                                  --------         --------         --------
                                                                                (in thousands)
                                                                                           
Oil and gas producing activities:
  Future cash inflows                                             $ 12,670         $  7,807         $  1,314
  Future production costs                                           (6,704)          (4,572)          (1,058)
                                                                  --------         --------         --------

                                                                     5,966            3,235              256
  10% annual discount factor                                        (3,391)          (1,487)             (67)
                                                                  --------         --------         --------

  Standardized measure of discounted future net cash flows        $  2,575         $  1,748         $    189
                                                                  ========         ========         ========



                                       11
   1663



                                                      For the years ended December 31,
                                                     ---------------------------------
                                                      2000         1999         1998
                                                     -------      -------      -------
                                                             (in thousands)
                                                                      
Oil and Gas Producing Activities:
  Oil and gas sales, net of production costs         $  (403)     $  (168)     $   (91)
  Net changes in prices and production costs             840          719         (692)
  Revisions of previous quantity estimates               844        1,623         (150)
  Accretion of discount                                  175           19          106
  Changes in production rates, timing and other         (629)        (634)         (48)
                                                     -------      -------      -------

  Change in present value of future net revenues         827        1,559         (875)
                                                     -------      -------      -------

  Balance, beginning of year                           1,748          189        1,064
                                                     -------      -------      -------

  Balance, end of year                               $ 2,575      $ 1,748      $   189
                                                     =======      =======      =======


NOTE 8. MAJOR CUSTOMERS

        The following table reflects the major customers of the Partnership's
oil and gas sales (a major customer is defined as a customer whose sales exceed
10% of total sales) during the years ended December 31:



                                              2000       1999       1998
                                            --------   --------   --------
                                                         
        Plains Marketing, L.P.                 56%         50%        -
        TEPPCO Crude Oil LLC                   10%         10%        -
        Genesis Crude Oil, L.P.                 -           -        47%
        Phillips Petroleum Company             17%         14%       12%
        Western Gas Resources, Inc.             2%          3%        9%


        At December 31, 2000, the amounts receivable from Plains Marketing,
L.P., Phillips Petroleum Company and TEPPCO Crude Oil LLC were $29,695, $12,633
and $4,023, respectively, which are included in the caption "Accounts receivable
- oil and gas sales" in the accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.


NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the Partnership agreement:

        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Program and Partnership affairs. As
        managing general partner and operator of the Partnership's properties,
        all production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a portion of the oil and
        gas revenue is initially received by Pioneer USA prior to being


                                       12
   1664

        paid to the Partnership. Under the Partnership agreement, the managing
        general partner pays 1% of the Partnership's acquisition, drilling and
        completion costs and 1% of its operating, general and administrative
        expenses. The managing general partner is also responsible for 1% of
        guaranty and loan commitment fees. In return, it is allocated 1% of the
        Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The partners entered into subscription
        agreements for aggregate capital contributions of $5,200,000. Pioneer
        USA is required to contribute amounts equal to 1% of initial Partnership
        capital less commission and organization and offering costs allocated to
        the limited partners and to contribute amounts necessary to pay costs
        and expenses allocated to it under the Partnership agreement to the
        extent that its share of revenues does not cover such costs.


                                       13
   1665

             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.
                        (A DELAWARE LIMITED PARTNERSHIP)

THIS REPORT CONTAINS FORWARD LOOKING STATEMENTS THAT INVOLVE RISKS AND
UNCERTAINTIES. ACCORDINGLY, NO ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS
AND RESULTS WILL NOT BE MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS
DESCRIBED IN THE FORWARD LOOKING STATEMENTS.

MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
   RESULTS OF OPERATIONS

In September 2000, restated financial statements for 1999 and 1998 were issued
to the partners to correct a revenue allocation error for one well in the
Partnership. The 1999 and 1998 amounts contained in the following discussion of
financial condition and the results of operation are based on the restated
amounts.

Results of operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 85% to $638,385 from 2000 as
compared to $345,743 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 16,344 barrels
of oil, 6,249 barrels of natural gas liquids ("NGLs") and 22,121 mcf of gas were
sold, or 26,280 barrel of oil equivalents ("BOEs"). In 1999, 15,384 barrels of
oil, 5,304 barrels of NGLs and 19,579 mcf of gas were sold, or 23,951 BOEs. Due
to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.13, or 71%, from
$17.04 in 1999 to $29.17 in 2000. The average price received per barrel of NGLs
increased $5.86, or 60%, from $9.70 in 1999 to $15.56 in 2000. The average price
received per mcf of gas increased 76% from $1.65 in 1999 to $2.91 in 2000. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

Total costs and expenses increased in 2000 to $297,927 as compared to $276,234
in 1999, an increase of $21,693, or 8%. The increase was due to increases in
production costs and general and administrative expenses ("G&A"), offset by a
decline in depletion.

Production costs were $235,823 in 2000 and $177,422 in 1999, resulting in a
$58,401 increase, or 33%. The increase was primarily due to higher production
taxes associated with higher oil and gas prices and additional well maintenance
costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A increased
42% from $14,767 in 1999 to $20,910 in 2000, primarily due to a higher
percentage of the managing general partner's G&A being allocated (limited to 3%
of oil and gas revenues) as a result of increased oil and gas revenues. The
Partnership paid the managing general partner $18,935 in 2000 and $11,455 in
1999 for G&A incurred on behalf of the Partnership. The remaining G&A was paid
directly by the Partnership. The managing general partner determines the
allocated expenses based upon the level of activity of the Partnership relative
to the non-partnership activities of the managing general partner. The method of
allocation has been consistent over the past several years with certain
modifications incorporated to reflect changes in Pioneer USA's overall business
activities.

Depletion was $41,194 in 2000 as compared to $84,045 in 1999, representing a
decrease of $42,851, or 51%. This decrease was primarily due to a 106,156
barrels of oil increase in proved reserves during 2000 as a result of higher
commodity prices.



   1666
1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 25% to $345,743 from
$275,856 in 1998. The increase in revenues resulted from higher average prices
received and an increase in production. In 1999, 15,384 barrels of oil, 5,304
barrels of NGLs and 19,579 mcf of gas were sold, or 23,951 BOEs. In 1998, 15,196
barrels of oil, 5,639 barrels of NGLs and 24,095 mcf of gas were sold, or 24,851
BOEs.

The average price received per barrel of oil increased $3.98, or 30%, from
$13.06 in 1998 to $17.04 in 1999. The average price received per barrel of NGLs
increased $2.81, or 41%, from $6.89 in 1998 to $9.70 in 1999. The average price
received per mcf of gas increased 3% from $1.60 in 1998 to $1.65 in 1999.

Gain on disposition of assets of $213 recognized during 1998 was related to
equipment salvage received on a well plugged and abandoned in a prior year.

Total costs and expenses decreased in 1999 to $276,234 as compared to $413,082
in 1998, a decrease of $136,848, or 33%. The decrease was due to reductions in
the impairment of oil and gas properties, depletion and production costs, offset
by an increase in G&A.

Production costs were $177,422 in 1999 and $184,952 in 1998, resulting in a
$7,530 decrease, or 4%. The decrease was due to reductions in well maintenance
costs and ad valorem taxes.

During this period, G&A increased 35% from $10,935 in 1998 to $14,767 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $11,455 in
1999 and $9,241 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $90,823 related to its oil and gas properties during 1998.

Depletion was $84,045 in 1999 compared to $126,372 in 1998, representing a
decrease of $42,327, or 33%. This decrease was primarily due to an increase in
proved reserves of 151,444 barrels of oil during 1999 as a result of higher
commodity prices and a reduction in the Partnership's net depletable basis from
charges taken in accordance with SFAS 121 during the fourth quarter of 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.


   1667

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $102,509 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $294,870, offset by increases in production costs paid
of $58,401, G&A expenses paid of $6,143 and working capital of $127,817. The
increase in oil and gas receipts resulted from the increase in commodity prices
during 2000 which contributed an additional $244,760 to oil and gas receipts and
an increase of $50,110 resulting from the increase in production during 2000.
The increase in production costs was primarily due to increased production taxes
associated with higher oil and gas prices and additional well maintenance costs
incurred to stimulate well production. The increase in G&A was primarily due to
higher percentage of the managing general partner's G&A being allocated (limited
to 3% of oil and gas revenues) as a result of increased oil and gas revenues.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on active properties.

Proceeds from asset dispositions of $3,269 in 1999 were due to equipment credits
received on active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $308,005, of which $3,080 was
distributed to the managing general partner and $304,925 to the limited
partners. In 1999, cash distributions to the partners were $140,741, of which
$1,407 was distributed to the managing general partner and $139,334 to the
limited partners.

   1668




             PARKER & PARSLEY 90 SPRABERRY PRIVATE DEVELOPMENT, L.P.


SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
                                                                        (Restated)   (Restated)
Operating results:
  Oil and gas sales                $          $  144,982   $  638,385   $  345,743   $  275,856   $  432,783   $  522,399
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $   90,823   $  257,009   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $   69,372   $  345,899   $   72,722   $ (133,234)  $ (152,931)  $  203,213
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net
    income (loss):
         Managing general
           partner                 $          $      694   $    3,459   $      727   $   (1,332)  $   (1,529)  $    2,032
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

         Limited partners          $          $   68,678   $  342,440   $   71,995   $ (131,902)  $ (151,402)  $  201,181
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $   528.29   $ 2,634.15   $   553.81   $(1,014.63)  $(1,164.63)  $ 1,547.55
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $   667.21   $ 2,345.58   $ 1,071.80   $ 1,098.82   $ 1,762.53   $ 1,836.00
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Total assets                     $          $  770,965   $  759,071   $  790,150   $  818,273   $1,064,821   $1,450,363
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========



   1669
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 91-A, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                 PROXY STATEMENT/PROSPECTUS DATED        , 2001

                                   ----------

                  THE DATE OF THIS SUPPLEMENT IS        , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
91-A, L.P., and supplements the proxy statement/prospectus dated        , 2001,
of Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 91-A, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000


                                       -1-
   1670
                           PARKER & PARSLEY 91-A, L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                             
Aggregate Initial Investment by the Limited Partners(a)                                         $   11,620

Aggregate Historical Limited Partner Distributions through July 31, 2001(a)                     $    9,928

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding
Pioneer USA(a), (b)                                                                             $    4,644

Merger Value per $1,000 Limited Partner Investment(b), (c)                                      $   401.24

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the             3.64 times
past four quarterly distributions including the distribution in July 2001(b), (c)

Book Value per $1,000 Limited Partner Investment:

        -- as of March 31, 2001(c)                                                              $   199.81

        -- as of December 31, 2000(c)                                                           $   206.61

Going Concern Value per $1,000 Limited Partner Investment(c), (d)                               $   376.51

Liquidation Value per $1,000 Limited Partner Investment(c), (e)                                 $   389.20

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment(c), (f)   $      158



----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2041, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                       -2-
   1671

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-38582-01


                           PARKER & PARSLEY 91-A, L.P.
             (Exact name of Registrant as specified in its charter)

                        Delaware                              75-2387572
            ----------------------------------          ---------------------
             (State or other jurisdiction of               (I.R.S. Employer
             incorporation or organization)             Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas     75039
----------------------------------------------------------------   ----------
            (Address of principal executive offices)               (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                         if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                Yes [x]  No [ ]






   1672



                           PARKER & PARSLEY 91-A, L.P.

                                TABLE OF CONTENTS




                                                                         Page

                                                                      
                          Part I. Financial Information

Item 1.     Financial Statements

            Balance Sheets as of March 31, 2001 and
               December 31, 2000.....................................    3

            Statements of Operations for the three months
              ended March 31, 2001 and 2000..........................    4

            Statement of Partners' Capital for the three months
              ended March 31, 2001...................................    5

            Statements of Cash Flows for the three months
              ended March 31, 2001 and 2000..........................    6

            Notes to Financial Statements............................    7

Item 2.     Management's Discussion and Analysis of Financial
              Condition and Results of Operations....................    7


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K.........................    9

            Signatures...............................................   10



                                        2

   1673



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                          Part 1. Financial Information

Item 1.      Financial Statements

                                 BALANCE SHEETS



                                                       March 31,    December 31,
                                                         2001          2000
                                                     -----------    -----------
                                                     (Unaudited)
                                                              
                 ASSETS
Current assets:
  Cash                                                $  203,216     $  219,827
  Accounts receivable - oil and gas sales                235,350        255,270
                                                      ----------     ----------
        Total current assets                             438,566        475,097
                                                      ----------     ----------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                 9,711,989      9,710,132
Accumulated depletion                                 (7,761,138)    (7,727,573)
                                                      ----------     ----------
        Net oil and gas properties                     1,950,851      1,982,559
                                                      ----------     ----------
                                                      $2,389,417     $2,457,656
                                                      ==========     ==========
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                        $   44,084     $   32,513

Partners' capital:
  Managing general partner                                23,497         24,295
  Limited partners (11,620 interests)                  2,321,836      2,400,848
                                                      ----------     ----------
                                                       2,345,333      2,425,143
                                                      ----------     ----------
                                                      $2,389,417     $2,457,656
                                                      ==========     ==========




  The financial information included as of March 31, 2001 has been prepared by
  the managing general partner without audit by independent public accountants.

   The accompanying notes are an integral part of these financial statements.



                                        3

   1674



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)





                                                      Three months ended
                                                           March 31,
                                                   -------------------------
                                                      2001           2000
                                                   ----------     ----------
                                                            
Revenues:
  Oil and gas                                       $ 452,460      $ 424,423
  Interest                                              3,530          3,363
                                                    ---------      ---------
                                                      455,990        427,786
                                                    ---------      ---------
Costs and expenses:
  Oil and gas production                              160,852        147,769
  General and administrative                           21,056         10,466
  Depletion                                            33,565         48,206
                                                    ---------      ---------
                                                      215,473        206,441
                                                    ---------      ---------
Net income                                          $ 240,517      $ 221,345
                                                    =========      =========

Allocation of net income:
  Managing general partner                          $   2,405      $   2,213
                                                    =========      =========
  Limited partners                                  $ 238,112      $ 219,132
                                                    =========      =========
Net income per limited partnership interest         $   20.49      $   18.86
                                                    =========      =========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        4

   1675



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)







                                  Managing
                                  general           Limited
                                  partner           partners           Total
                                -----------       -----------       -----------


                                                           
Balance at January 1, 2001      $    24,295       $ 2,400,848       $ 2,425,143

    Distributions                    (3,203)         (317,124)         (320,327)

    Net income                        2,405           238,112           240,517
                                -----------       -----------       -----------

Balance at March 31, 2001       $    23,497       $ 2,321,836       $ 2,345,333
                                ===========       ===========       ===========







         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        5

   1676



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)




                                                          Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------     ---------
                                                                
Cash flows from operating activities:
  Net income                                            $ 240,517      $221,345
  Adjustment to reconcile net income to net
    cash provided by operating activities:
       Depletion                                           33,565        48,206
  Changes in assets and liabilities:
       Accounts receivable                                 19,920       (25,246)
       Accounts payable                                    11,571       (13,066)
                                                        ---------      --------
          Net cash provided by operating activities       305,573       231,239
                                                        ---------      --------
Cash flows from investing activities:
  Additions to oil and gas properties                      (1,857)       (4,637)
  Proceeds from disposition of assets                          --         8,812
                                                        ---------      --------
          Net cash provided by (used in) investing
            activities                                     (1,857)        4,175
                                                        ---------      --------
Cash flows used in financing activities:
  Cash distributions to partners                         (320,327)     (243,701)
                                                        ---------      --------
Net decrease in cash                                      (16,611)       (8,287)
Cash at beginning of period                               219,827       226,846
                                                        ---------      --------
Cash at end of period                                   $ 203,216      $218,559
                                                        =========      ========





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.

                                        6

   1677



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of organization

Parker & Parsley 91-A, L.P. (the "Partnership") is a limited partnership
organized in 1991 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's Report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
            and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues increased 7% to $452,460 for the three
months ended March 31, 2001 as compared to $424,423 for the same period in 2000.
The increase in revenues resulted from higher average prices received, offset by
a decrease in production. For the three months ended March 31, 2001, 10,545
barrels of oil, 2,575 barrels of natural gas liquids ("NGLs") and 19,051 mcf of
gas were sold, or 16,295 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 11,360 barrels of oil, 4,839 barrels of NGLs and
22,979 mcf of gas were sold, or 20,029 BOEs.

                                        7

   1678




The average price received per barrel of oil increased slightly from $27.88 for
the three months ended March 31, 2000 to $27.99 for the same period in 2001. The
average price received per barrel of NGLs increased $1.21, or 9%, from $13.65
for the three months ended March 31, 2000 to $14.86 for the same period in 2001.
The average price received per mcf of gas increased 245% from $1.81 during the
three months ended March 31, 2000 to $6.25 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Costs and Expenses:

Total costs and expenses increased to $215,473 for the three months ended March
31, 2001 as compared to $206,441 for the same period in 2000, an increase of
$9,032, or 4%. This increase was due to increases in production costs and
general and administrative expenses ("G&A"), offset by a decline in depletion.

Production costs were $160,852 for the three months ended March 31, 2001 and
$147,769 for the same period in 2000 resulting in a $13,083 increase, or 9%.
This increase was primarily due to additional well maintenance costs incurred to
stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 101% from $10,466 for the three months ended March 31, 2000 to $21,056
for the same period in 2001. The G&A increase was primarily due to an increase
in the accrual for tax preparation and monitoring service fees.

Depletion was $33,565 for the three months ended March 31, 2001 as compared to
$48,206 for the same period in 2000, a decrease of $14,641, or 30%. This
decrease was primarily due to positive revisions to proved reserves during the
three months ended March 31, 2001 as a result of higher commodity prices, a
reduction in the Partnership's net depletable basis from charges taken in
accordance with Statement of Financial Accounting Standards No. 121, "Accounting
for the Impairment of Long-Lived Assets and for Long-Lived Assets to be Disposed
Of" ("SFAS 121") during the fourth quarter of 2000 and a decline in oil
production of 815 barrels for the three months ended March 31, 2001 as compared
to the same period in 2000.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $74,334 for the three months
ended March 31, 2001 from the same period in 2000. The increase was primarily
attributable to an increase of $28,204 in oil and gas sales receipts and a
reduction in working capital of $69,803, offset by increases in production costs
of $13,083 and G&A expenses of $10,590. The increase in oil and gas receipts
resulted from the increase in commodity prices during 2001 which contributed an
additional $109,197 to oil and gas receipts, offset by $80,993 resulting from
the decline in production during 2001 as compared to the same period in 2000.

                                        8

   1679



The increase in production costs was primarily due to increased well maintenance
costs incurred to stimulate well production. The G&A increase was primarily due
to the accrual for tax preparation and monitoring service fees.

Net Cash Provided by (Used in) Investing Activities

The Partnership's principal investing activities during the three months ended
March 31, 2001 and 2000 were related to the upgrades of oil and gas equipment on
active properties.

Proceeds from asset dispositions of $8,812 recognized during 2000 were from
equipment credits received on one active well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $320,327, of which $3,203 was distributed to the managing general partner
and $317,124 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $243,701, of which $2,437 was
distributed to the managing general partner and $241,264 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, requires a 66-2/3% approval of the
limited partnership interests in each partnership and the resolution of Security
and Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

     (a)   Exhibits - none

     (b)   Reports on Form 8-K - none.

                                        9

   1680


                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)



                                   SIGNATURES



       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 91-A, L.P.


                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 14, 2001                By:     /s/ Rich Dealy
                                            ---------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer



                                       10



   1681
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-38582-01


                           PARKER & PARSLEY 91-A, L.P.
             (Exact name of Registrant as specified in its charter)


                                                                           
               DELAWARE                                                                  75-2387572
   -------------------------------                                               --------------------------
   (State or other jurisdiction of                                                  (I.R.S. Employer
   incorporation or organization)                                                Identification Number)


1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                            75039
----------------------------------------------------------------                        -------------
          (Address of principal executive offices)                                        (Zip code)


       Registrant's Telephone Number, including area code: (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
                   Securities registered pursuant to Section
                               12(g) of the Act:
                LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)
                -----------------------------------------------

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$11,575,000.

       As of March 8, 2001, the number of outstanding limited partnership
interests was 11,620.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None

PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.
   1682

                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 91-A, L.P. (the "Partnership") is a limited partnership
organized in 1991 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 11,620 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 38% and 16% were attributable to sales
made to Plains Marketing, L.P. and TEPPCO Crude Oil LLC, respectively. Pioneer
USA is of the opinion that the loss of any one purchaser would not have an
adverse effect on its ability to sell its oil, natural gas liquids ("NGLs") and
gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial


                                        2

   1683

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2.    PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 48
oil and gas wells. One well has been plugged and abandoned. At December 31,
2000, the Partnership had 47 wells producing.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, see Note 7 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
below. Such reserves have been evaluated by Williamson Petroleum Consultants,
Inc., an independent petroleum consultant.

ITEM 3.    LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4.    SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.





                                        3

   1684

                                     PART II


ITEM 5.    MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
            DISTRIBUTIONS

At March 8, 2001, the Partnership had 11,620 outstanding limited partnership
interests held of record by 724 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations are distributed to the partners
at least quarterly in accordance with the limited partnership agreement. During
the years ended December 31, 2000 and 1999, distributions of $1,162,365 and
$432,629, respectively, were made to the limited partners.

ITEM 6.    SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                        2000            1999             1998            1997            1996
                                   -------------    -------------    ------------    -------------   -------------

                                                                                     
Operating results:
-----------------
  Oil and gas sales                $   1,899,948    $   1,140,335    $    955,645    $   1,411,247   $   1,629,975
                                    ============     ============     ===========     ============    ============

  Impairment of oil and gas
    properties                     $      12,824    $      66,898    $    306,043    $     485,158   $          -
                                    ============     ============     ===========     ============    ============

  Net income (loss)                $   1,115,704    $     266,803    $   (280,631)   $      (7,029)  $     654,054
                                    ============     ============     ===========     ============    ============

  Allocation of net income
   (loss):
     Managing general partner      $      11,157    $       2,668    $     (2,806)   $         (70)  $       6,540
                                    ============     ============     ===========     ============    ============

     Limited partners              $   1,104,547    $     264,135    $   (277,825)   $      (6,959)  $     647,514
                                    ============     ============     ===========     ============    ============

  Limited partners' net income
    (loss) per limited
    partnership interest           $       95.06    $       22.73    $     (23.91)   $        (.60)  $       55.72
                                    ============     ============     ===========     ============    ============

  Limited partners' cash
    distributions per limited
    partnership interest           $      100.03    $       37.23    $      36.77    $       75.11   $       70.97
                                    ============     ============     ===========     ============    ============

At year end:
-----------
  Identifiable assets              $   2,457,656    $   2,531,606    $  2,667,803    $   3,402,546   $   4,289,878
                                    ============     ============     ===========     ============    ============




                                        4

   1685
ITEM 7.    MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
            RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 67% to $1,899,948 for 2000 as
compared to $1,140,335 in 1999. The increase in revenues resulted from higher
average prices received, offset by a decline in production. In 2000, 43,704
barrels of oil, 20,425 barrels of natural gas liquids ("NGLs") and 94,315 mcf of
gas were sold, or 79,848 barrel of oil equivalents ("BOEs"). In 1999, 44,203
barrels of oil, 20,617 barrels of NGLs and 100,615 mcf of gas were sold, or
81,589 BOEs. Due to the decline characteristics of the Partnership's oil and gas
properties, management expects a certain amount of decline in production in the
future until the Partnership's economically recoverable reserves are fully
depleted.

The average price received per barrel of oil increased $12.33, or 70%, from
$17.57 in 1999 to $29.90 in 2000. The average price received per barrel of NGLs
increased $5.60, or 60%, from $9.34 in 1999 to $14.94 in 2000. The average price
received per mcf of gas increased 80% from $1.70 in 1999 to $3.06 in 2000. The
market price for oil and gas has been extremely volatile in the past decade and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received in 2000.

A gain on disposition of assets of $1,096 recognized during 1999 was from
equipment credits received on one temporarily abandoned property.

Total costs and expenses decreased in 2000 to $802,130 as compared to $884,937
in 1999, a decrease of $82,807, or 9%. The decrease was due to declines in
depletion, the impairment of oil and gas properties and general and
administrative expenses ("G&A"), offset by an increase in production costs.

Production costs were $589,344 in 2000 and $514,994 in 1999, resulting in an
increase of $74,350, or 14%. This increase was primarily due to higher
production taxes associated with higher oil and gas prices and additional well
maintenance costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A decreased
21% from $75,454 in 1999 to $59,962 in 2000. The Partnership paid the managing
general partner $41,213 in 2000 and $34,110 in 1999 for G&A incurred on behalf
of the Partnership. The remaining G&A was paid directly by the Partnership. The
managing general partner determines the allocated expenses based upon the level
of activity of the Partnership relative to the non-partnership activities of the
managing general partner. The method of allocation has been consistent over the
past several years with certain modifications incorporated to reflect changes in
Pioneer USA's overall business activities.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized
non-cash charges of $12,824 and $66,898 related to its oil and gas properties
during 2000 and 1999, respectively.

                                        5

   1686
Depletion decreased in 2000 to $140,000 as compared to $227,591 in 1999,
representing a decrease of $87,591, or 38%. This decrease was primarily due to a
127,977 barrels of oil increase in proved reserves during 2000 as a result of
higher commodity prices and a reduction in the Partnership's net depletable
basis from charges taken in accordance with SFAS 121 during the fourth quarter
of 1999.

1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 19% to $1,140,335 from
$955,645 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 44,203 barrels of oil,
20,617 barrels of NGLs and 100,615 mcf of gas were sold, or 81,589 BOEs. In
1998, 49,403 barrels of oil, 21,220 barrels of NGLs and 108,617 mcf of gas were
sold, or 88,726 BOEs.

The average price received per barrel of oil increased $4.42, or 34%, from
$13.15 in 1998 to $17.57 in 1999. The average price received per barrel of NGLs
increased $2.90, or 45%, from $6.44 in 1998 to $9.34 in 1999. The average price
received per mcf of gas increased 9% from $1.56 in 1998 to $1.70 in 1999.

A gain on disposition of assets of $1,096 recognized during 1999 was from
equipment credits received on one temporarily abandoned property.

Total costs and expenses decreased in 1999 to $884,937 as compared to $1,247,302
in 1998, a decrease of $362,365, or 29%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $514,994 in 1999 and $535,948 in 1998, resulting in a
decrease of $20,954, or 4%. This decrease resulted from declines in ad valorem
taxes, well maintenance costs and workover costs, offset by an increase in
production taxes due to increased oil and gas revenues.

During this period, G&A increased 72% from $43,977 in 1998 to $75,454 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $34,110 in
1999 and $24,415 in 1998 for G&A incurred on behalf of the Partnership.

The Partnership recognized non-cash SFAS 121 charges of $66,898 and $306,043
related to its oil and gas properties during 1999 and 1998, respectively.

Depletion decreased in 1999 to $227,591 as compared to $361,334 in 1998. This
represented a decrease of $133,743, or 37%. This decrease was the result of an
increase in proved reserves of 281,767 barrels of oil during 1999 as a result of
higher commodity prices, a reduction in the Partnership's net depletable basis
from charges taken in accordance with SFAS 121 during the fourth quarter of 1998
and a decline in oil production of 5,200 barrels for the period ended December
31, 1999 compared to the same period in 1998.

Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998,


                                        6

   1687
weather patterns, regional economic recessions and political matters combined to
cause worldwide oil supplies to exceed demand resulting in a substantial decline
in oil prices. Also during 1998, but to a lesser extent, market prices for
natural gas declined. During 1999 and 2000, the Organization of Petroleum
Exporting Countries ("OPEC") and certain other crude oil exporting nations
announced reductions in their planned export volumes. Those announcements,
together with the enactment of the announced reductions in export volumes, had a
positive impact on world oil prices, as have overall natural gas supply and
demand fundamentals on North American natural gas prices. Although the favorable
commodity price environment and stable field service cost environment is
expected to continue during 2001, there is no assurance that commodity prices
will not return to a less favorable level or that field service costs will not
escalate in the future, both of which could negatively impact the Partnership's
future results of operations and cash distributions.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $647,967 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $767,190 and a decline in G&A expenses paid of
$15,492, offset by an increase in production costs paid of $74,350 and working
capital of $60,365. The increase in oil and gas receipts resulted from the
increase in commodity prices during 2000 which contributed an additional
$804,227 to oil and gas receipts, offset by $37,037 resulting from the decline
in production during 2000. The increase in production costs was primarily due to
increased production taxes associated with higher oil and gas prices and
additional well maintenance costs incurred to stimulate well production.

Net Cash Used in Investing Activities

The Partnership's investing activities during 2000 and 1999 included
expenditures related to equipment upgrades on various oil and gas properties.

Proceeds from asset dispositions of $11,549 and $1,096 recognized during 2000
and 1999, respectively, were from the disposition of oil and gas equipment on
active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $1,174,106, of which $11,741
was distributed to the managing general partner and $1,162,365 to the limited
partners. In 1999, cash distributions to the partners were $436,999, of which
$4,370 was distributed to the managing general partner and $432,629 to the
limited partners.


                                        7

   1688



ITEM 8.    FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                               Page
                                                                               ----

                                                                           
Financial Statements of Parker & Parsley 91-A, L.P.:
  Independent Auditors' Report.............................................      9
  Balance Sheets as of December 31, 2000 and 1999..........................     10
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998....................................................     11
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998.......................................     12
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998....................................................     13
  Notes to Financial Statements............................................     14










                                        8

   1689



                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 91-A, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 91-A, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 91-A, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.



                                                 Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                        9

   1690



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                                 2000                1999
                                                                            --------------      -------------
                 ASSETS
                 ------

                                                                                          
Current assets:
  Cash                                                                      $      219,827      $     226,846
  Accounts receivable - oil and gas sales                                          255,270            177,988
                                                                             -------------       ------------

          Total current assets                                                     475,097            404,834
                                                                             -------------       ------------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                           9,710,132          9,701,521
Accumulated depletion                                                           (7,727,573)        (7,574,749)
                                                                             -------------       ------------

          Net oil and gas properties                                             1,982,559          2,126,772
                                                                             -------------       ------------

                                                                            $    2,457,656      $   2,531,606
                                                                             =============       ============

LIABILITIES AND PARTNERS' CAPITAL
---------------------------------

Current liabilities:
  Accounts payable - affiliate                                              $       32,513      $      48,061

Partners' capital:
  Managing general partner                                                          24,295             24,879
  Limited partners (11,620 interests)                                            2,400,848          2,458,666
                                                                             -------------       ------------

                                                                                 2,425,143          2,483,545
                                                                             -------------       ------------

                                                                            $    2,457,656      $   2,531,606
                                                                             =============       ============

















   The accompanying notes are an integral part of these financial statements.

                                       10

   1691



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                                  2000              1999             1998
                                                             -------------     ------------     -------------

                                                                                      
Revenues:
  Oil and gas                                                $   1,899,948     $  1,140,335     $     955,645
  Interest                                                          17,886           10,309            11,026
  Gain on disposition of assets                                        -              1,096               -
                                                              ------------      -----------      ------------

                                                                 1,917,834        1,151,740           966,671
                                                              ------------      -----------      ------------

Costs and expenses:
  Oil and gas production                                           589,344          514,994           535,948
  General and administrative                                        59,962           75,454            43,977
  Impairment of oil and gas properties                              12,824           66,898           306,043
  Depletion                                                        140,000          227,591           361,334
                                                              ------------      -----------      ------------

                                                                   802,130          884,937         1,247,302
                                                              ------------      -----------      ------------

Net income (loss)                                            $   1,115,704     $    266,803     $    (280,631)
                                                              ============      ===========      ============

Allocation of net income (loss):
  Managing general partner                                   $      11,157     $      2,668     $      (2,806)
                                                              ============      ===========      ============

  Limited partners                                           $   1,104,547     $    264,135     $    (277,825)
                                                              ============      ===========      ============

Net income (loss) per limited partners' interest             $       95.06     $      22.73     $      (23.91)
                                                              ============      ===========      ============















   The accompanying notes are an integral part of these financial statements.

                                       11

   1692



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                               Managing
                                                               general           Limited
                                                               partner           partners            Total
                                                             -----------        -----------      ------------



                                                                                      
Partners' capital at January 1, 1998                        $     33,702       $  3,332,223     $   3,365,925

     Distributions                                                (4,315)          (427,238)         (431,553)

     Net loss                                                     (2,806)          (277,825)         (280,631)
                                                             -----------        -----------      ------------

Partners' capital at December 31, 1998                            26,581          2,627,160         2,653,741

     Distributions                                                (4,370)          (432,629)         (436,999)

     Net income                                                    2,668            264,135           266,803
                                                             -----------        -----------      ------------

Partners' capital at December 31, 1999                            24,879          2,458,666         2,483,545

     Distributions                                               (11,741)        (1,162,365)       (1,174,106)

     Net income                                                   11,157          1,104,547         1,115,704
                                                             -----------        -----------      ------------

Partners' capital at December 31, 2000                      $     24,295       $  2,400,848     $   2,425,143
                                                             ===========        ===========      ============














   The accompanying notes are an integral part of these financial statements.

                                       12

   1693



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31





                                                                 2000              1999             1998
                                                             ------------      ------------     ------------

                                                                                      
Cash flows from operations:
  Net income (loss)                                          $  1,115,704      $    266,803     $   (280,631)
  Adjustment to reconcile net income (loss) to net
     cash provided by operating activities:
       Impairment of oil and gas properties                        12,824            66,898          306,043
       Depletion                                                  140,000           227,591          361,334
       Gain on disposition of assets                                   -             (1,096)              -
  Changes in assets and liabilities:
       Accounts receivable                                        (77,282)          (66,464)          54,318
       Accounts payable                                           (15,548)           33,999          (22,559)
                                                              -----------       -----------      -----------

         Net cash provided by operating
           activities                                           1,175,698           527,731          418,505
                                                              -----------       -----------      -----------

Cash flows from investing activities:
  Additions to oil and gas properties                             (20,160)          (23,360)         (15,294)
  Proceeds from asset disposition                                  11,549             1,096            5,617
                                                              -----------       -----------      -----------

         Net cash used in investing activities                     (8,611)          (22,264)          (9,677)
                                                              -----------       -----------      -----------

Cash flows used in financing activities:
  Cash distributions to partners                               (1,174,106)         (436,999)        (431,553)
                                                              -----------       -----------      -----------

Net increase (decrease) in cash                                    (7,019)           68,468          (22,725)
Cash at beginning of year                                         226,846           158,378          181,103
                                                              -----------       -----------      -----------

Cash at end of year                                          $    219,827      $    226,846     $    158,378
                                                              ===========       ===========      ===========











   The accompanying notes are an integral part of these financial statements.

                                       13

   1694



                           PARKER & PARSLEY 91-A, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998


NOTE 1.    ORGANIZATION AND NATURE OF OPERATIONS

       Parker & Parsley 91-A, L.P. (the "Partnership") is a limited partnership
organized in 1991 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

       The Partnership engages in oil and gas development and production in
Texas and is not involved in any industry segment other than oil and gas.

NOTE 2.    SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

       A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

       Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the unit-of-
production method on a property-by-property basis based on proved oil (dominant
mineral) reserves as evaluated by independent petroleum consultants. The
carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

       Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

       Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.

       Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

       Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.


                                       14

   1695



       Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

       General and administrative expenses - General and administrative expenses
are allocated, in part, to the Partnership by the managing general partner.
Allocated expenses are determined by the managing general partner based upon the
level of activity of the Partnership relative to the non-partnership activities
of the managing general partner. The method of allocation has been consistent
over the past several years with certain modifications incorporated to reflect
changes in Pioneer USA's overall business activities.

       Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

       Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

       Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3.    IMPAIRMENT OF LONG-LIVED ASSETS

       In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized non-cash impairment provisions of $12,824, $66,898 and
$306,043 related to its proved oil and gas properties during 2000, 1999 and
1998, respectively.

                                       15

   1696




NOTE 4.    INCOME TAXES

       The financial statement basis of the Partnership's net assets and
liabilities was $946,627 greater than the tax basis at December 31, 2000.

       The following is a reconciliation of net income (loss) per statements of
operations with the net income per Federal income tax returns for the years
ended December 31:



                                                                 2000              1999              1998
                                                            -------------     -------------     ------------

                                                                                      
Net income (loss) per statements of operations              $   1,115,704     $     266,803     $   (280,631)
Depletion and depreciation provisions for tax
   reporting purposes (greater than) less than
   amounts for financial reporting purposes                       120,160           106,971          (11,376)
Impairment of oil and gas properties for financial
   reporting purposes                                              12,824            66,898          306,043
Other, net                                                          8,901            (4,139)           8,462
                                                             ------------      ------------      -----------

     Net income per Federal income tax
       returns                                              $   1,257,589     $     436,533     $     22,498
                                                             ============      ============      ===========


NOTE 5.    OIL AND GAS PRODUCING ACTIVITIES

       The following is a summary of the costs incurred, whether capitalized or
expensed, related to the Partnership's oil and gas producing activities for the
years ended December 31:



                                                                 2000              1999              1998
                                                            -------------     -------------     ------------

                                                                                      
     Development costs                                      $      20,160     $      23,360     $     15,294
                                                             ============      ============      ===========


       Capitalized oil and gas properties consist of the following:



                                                                               2000                  1999
                                                                          --------------        -------------

                                                                                         
     Property acquisition costs                                           $      343,666        $     343,666
     Completed wells and equipment                                             9,366,466            9,357,855
                                                                           -------------         ------------

                                                                               9,710,132            9,701,521
       Accumulated depletion                                                  (7,727,573)          (7,574,749)
                                                                           -------------         ------------

                Net oil and gas properties                                $    1,982,559        $   2,126,772
                                                                           =============         ============


NOTE 6.    RELATED PARTY TRANSACTIONS

       Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                                                   2000              1999             1998
                                                              --------------    --------------   --------------

                                                                                       
   Payment of lease operating and supervision
     charges in accordance with standard industry
     operating agreements                                     $   202,739       $   213,969      $   210,197

   Reimbursement of general and administrative
     expenses                                                 $    41,213       $    34,110      $    24,415




                                       16

   1697

       The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 91-A GP ("EMPL") and the Partnership are parties to the Program
agreement. EMPL is a general partnership organized for the benefit of certain
employees of Pioneer USA. EMPL was merged with Pioneer USA on December 28, 2000.

       The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                           Pioneer USA (1)       Partnership (1)
                                                                           ---------------       ---------------

                                                                                           
     Revenues:
       Proceeds from disposition of depreciable and depletable
         properties                                                           34.3434343%         65.6565657%
       All other revenues                                                     34.3434343%         65.6565657%

     Costs and expenses:
       Lease acquisition costs, drilling and completion costs
         and all other costs                                                  24.2424242%         75.7575758%
       Operating costs, reporting and legal expenses and
         general and administrative expenses                                  34.3434343%         65.6565657%


      (1)   Includes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 45 limited partner interests
            owned by Pioneer USA.

NOTE 7.    OIL AND GAS INFORMATION (UNAUDITED)

       The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                                                            Oil and NGLs              Gas
                                                                               (bbls)                (mcf)
                                                                           -------------          ------------


                                                                                            
   Net proved reserves at January 1, 1998                                        909,941             1,063,660
   Revisions                                                                    (333,709)             (228,660)
   Production                                                                    (70,623)             (108,617)
                                                                           -------------          ------------

   Net proved reserves at December 31, 1998                                      505,609               726,383
   Revisions                                                                     430,559               692,465
   Production                                                                    (64,820)             (100,615)
                                                                           -------------          ------------

   Net proved reserves at December 31, 1999                                      871,348             1,318,233
   Revisions                                                                     171,624               199,837
   Production                                                                    (64,129)              (94,315)
                                                                           -------------          ------------

   Net proved reserves at December 31, 2000                                      978,843             1,423,755
                                                                           =============          ============






                                       17

   1698
       As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.72
per barrel of oil, $12.21 per barrel of NGLs and $7.85 per mcf of gas,
discounted at 10% was approximately $8,217,000 and undiscounted was $17,966,000.

       Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

      The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

      Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider probable reserves, anticipated
future oil and gas prices, interest rates, changes in development and production
costs and risks associated with future production. Because of these and other
considerations, any estimate of fair value is necessarily subjective and
imprecise.



                                                                          For the years ended December 31,
                                                                  ----------------------------------------------
                                                                       2000             1999            1998
                                                                  -------------    -------------   -------------
                                                                                   (in thousands)
                                                                                         
Oil and gas producing activities:
   Future cash inflows                                            $      32,836    $      21,453   $       5,509
   Future production costs                                              (14,870)         (11,854)         (4,104)
                                                                   ------------     ------------    ------------

                                                                         17,966            9,599           1,405
   10% annual discount factor                                            (9,749)          (4,661)           (456)
                                                                   ------------     ------------    ------------

   Standardized measure of discounted future net cash flows       $       8,217    $       4,938   $         949
                                                                   ============     ============    ============





                                       18

   1699






                                                                          For the years ended December 31,
                                                                  ----------------------------------------------
                                                                       2000             1999            1998
                                                                  -------------    -------------   -------------
                                                                                  (in thousands)
                                                                                         
   Oil and Gas Producing Activities:
     Oil and gas sales, net of production costs                   $      (1,311)   $        (625)  $        (420)
     Net changes in prices and production costs                           3,414            2,743          (2,438)
     Revisions of previous quantity estimates                             1,558            3,245            (441)
     Accretion of discount                                                  494               95             391
     Changes in production rates, timing and other                         (876)          (1,469)            (48)
                                                                   ------------     ------------    ------------

     Change in present value of future net revenues                       3,279            3,989          (2,956)
                                                                   ------------     ------------    ------------

     Balance, beginning of year                                           4,938              949           3,905
                                                                   ------------     ------------    ------------

     Balance, end of year                                         $       8,217    $       4,938   $         949
                                                                   ============     ============    ============


NOTE 8.    MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership`s oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the years ended December 31:



                                                                2000              1999             1998
                                                              --------          --------         --------

                                                                                          
                Plains Marketing, L.P.                           38%               36%                -
                TEPPCO Crude Oil LLC                             16%               17%                -
                Genesis Crude Oil, L.P.                           -                 -                52%
                Western Gas Resources, Inc.                       3%                5%               19%


       At December 31, 2000, the amounts receivable from Plains Marketing, L.P.
and TEPPCO Crude Oil LLC were $64,973 and $19,274, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

       Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9.    PARTNERSHIP AGREEMENT

       The following is a brief summary of the more significant provisions of
the limited partnership agreement:

       Managing general partner - The managing general partner of the
       Partnership is Pioneer USA. Pioneer USA has the power and authority to
       manage, control and administer all Partnership affairs. As managing
       general partner and operator of the Partnership's properties, all
       production expenses are incurred by Pioneer USA and billed to the
       Partnership. The majority of the Partnership's oil and gas revenues are
       received directly by the Partnership, however, a portion of the oil and
       gas revenue is initially received by Pioneer USA prior to being paid to
       the Partnership. Under the limited partnership agreement, the managing
       general partner pays 1%



                                       19

   1700




       of the Partnership's acquisition, drilling and completion costs, and 1%
       of its operating and general and administrative expenses. In return it
       is allocated 1% of the Partnership's revenues.

          Limited partner liability - The maximum amount of liability of any
          limited partner is the total contributions of such partner plus his
          share of any undistributed profits.

          Initial capital contributions - The limited partners entered into
          subscription agreements for aggregate capital contributions of
          $11,620,000. The managing general partner is required to contribute
          amounts equal to 1% of initial Partnership capital less sales
          commission costs allocated to the limited partners and to contribute
          amounts necessary to pay costs and expenses allocated to it under the
          partnership agreement to the extent its share of revenues does not
          cover such costs.

ITEM 9.    CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
           AND FINANCIAL DISCLOSURE

None.



                                       20

   1701



                                    PART III


ITEM 10.   DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                               Age at
                                             December 31,
        Name                                    2000                              Position
        ----                                    ----                              --------

                                                           
Scott D. Sheffield                               48                 President

Timothy L. Dove                                  44                 Executive Vice President, Chief
                                                                      Financial Officer and Director

Dennis E. Fagerstone                             51                 Executive Vice President and Director

Mark L. Withrow                                  53                 Executive Vice President, General
                                                                      Counsel and Director

Danny Kellum                                     46                 Executive Vice President - Domestic
                                                                      Operations and Director

Rich Dealy                                       34                 Vice President and Chief Accounting
                                                                      Officer


         Scott D. Sheffield.  Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.

                                       21

   1702



       Timothy L. Dove.  Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

       Dennis E. Fagerstone.  Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

       Mark L. Withrow.  Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

       Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

       Rich Dealy.  Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.


                                       22

   1703



ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by the managing general partner. The Partnership
participates in oil and gas activities through an income tax partnership (the
"Program") pursuant to the Program agreement. Under the Program agreement,
Pioneer USA pays approximately 25% of the Program's acquisition, drilling and
completion costs and approximately 35% of its operating and general and
administrative expenses. In return, they are allocated approximately 35% of the
Program's revenues.

The Partnership does not directly pay any salaries of the executive officers or
employees of Pioneer USA, but does pay a portion of Pioneer USA's general and
administrative expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)    Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 45 limited partner interests at January 1, 2001.

(b)    Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13.   CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:






                                       23

   1704





                                                                2000               1999              1998
                                                             -----------        -----------       -----------
                                                                                       
   Payment of lease operating and supervision
      charges in accordance with standard
      industry operating agreements                          $   202,739        $   213,969       $   210,197

   Reimbursement of general and administrative
      expenses                                               $    41,213        $    34,110       $    24,415


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation in oil and gas activities of the
Program.



                                       24

   1705



                                     PART IV

ITEM 14.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)    1.     Financial statements

              The following are filed as part of this Report:

                    Independent Auditors' Report

                    Balance sheets as of December 31, 2000 and 1999

                    Statements of operations for the years ended December 31,
                      2000, 1999 and 1998

                    Statements of partners' capital for the years ended December
                      31, 2000, 1999 and 1998

                    Statements of cash flows for the years ended December 31,
                      2000, 1999 and 1998

                    Notes to financial statements

       2.     Financial statement schedules

              All financial statement schedules have been omitted since the
              required information is in the financial statements or notes
              thereto, or is not applicable nor required.

(b)    Reports on Form 8-K

None.

(c)    Exhibits

       The exhibits listed on the accompanying index to exhibits are filed or
       incorporated by reference as part of this Report.


                                       25

   1706



                               S I G N A T U R E S


       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                          PARKER & PARSLEY 91-A, L.P.

Dated:  March 26, 2001              By:   Pioneer Natural Resources USA, Inc.
                                            Managing General Partner


                                          By:   /s/ Scott D. Sheffield
                                                ------------------------------
                                                Scott D. Sheffield, President

       Pursuant to the requirements of the Securities Exchange Act of 1934, this
Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                                       
/s/ Scott D. Sheffield                      President of Pioneer USA                            March 26, 2001
-------------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                         Executive Vice President, Chief                     March 26, 2001
-------------------------------------       Financial Officer and Director of
Timothy L. Dove                             Pioneer USA


/s/ Dennis E. Fagerstone                    Executive Vice President and                        March 26, 2001
-------------------------------------       Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                         Executive Vice President, General                   March 26, 2001
-------------------------------------       Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                            Executive Vice President - Domestic                March 26, 2001
-------------------------------------       Operations and Director of Pioneer
Danny Kellum                                USA


/s/ Rich Dealy                              Vice President and Chief Accounting                 March 26, 2001
-------------------------------------       Officer of Pioneer USA
Rich Dealy



                                       26

   1707


                           PARKER & PARSLEY 91-A, L.P.

                                INDEX TO EXHIBITS


       The following documents are incorporated by reference in response to Item
14(c):



Exhibit No.                              Description                                   Page
-----------                              -----------                                   ----

                                                                                  
   3(a)                    Form of Agreement of Limited Partnership                       -
                           of Parker & Parsley 91-A, L.P. incorporated
                           by reference to Exhibit A of the Partnership's
                           Registration Statement on Form S-1
                           (Registration No. 33-38582) (hereinafter
                           called the Partnership's Registration Statement)

   4(b)                    Form of Limited Partner Subscription Agreement                 -
                           incorporated by reference to Exhibit C of the
                           Partnership's Registration Statement

   4(b)                    Form of General Partner Subscription Agreement                 -
                           incorporated by reference to Exhibit D of the
                           Partnership's Registration Statement

   4(b)                    Power of Attorney incorporated by reference to                 -
                           Exhibit B of the Partnership's Registration
                           Statement

   4(c)                    Specimen Certificate of Limited Partnership                  -
                           Interest incorporated by reference to Exhibit 4.3
                           of Amendment No. 2 of the Partnership's
                           Registration Statement

  10(b)                    Development Drilling Program Agreement                       -
                           incorporated by reference to Exhibit B of the
                           Partnership's Registration Statement





                                       27


   1708



                           PARKER & PARSLEY 91-A, L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  424,423   $1,899,948   $1,140,335   $  955,645   $1,411,247   $1,629,975
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $   12,824   $   66,898   $  306,043   $  485,158   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  221,345   $1,115,704   $  266,803   $ (280,631)  $   (7,029)  $  654,054
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
   (loss):
     Managing general
       partner                     $          $    2,213   $   11,157   $    2,668   $   (2,806)  $      (70)  $    6,540
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

     Limited partners              $          $  219,132   $1,104,547   $  264,135   $ (277,825)  $   (6,959)  $  647,514
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per
    limited partnership
    interest                       $          $    18.86   $    95.06   $    22.73   $   (23.91)  $     (.60)  $    55.72
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    20.76   $   100.03   $    37.23   $    36.77   $    75.11   $    70.97
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $2,496,184   $2,457,656   $2,531,606   $2,667,803   $3,402,546   $4,289,878
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1709
                        PIONEER NATURAL RESOURCES COMPANY
                       PIONEER NATURAL RESOURCES USA, INC.
                            1400 WILLIAMS SQUARE WEST
                            5205 NORTH O'CONNOR BLVD.
                               IRVING, TEXAS 75039

                            SUPPLEMENTAL INFORMATION

                                       OF

           PARKER & PARSLEY 91-B, L.P., A DELAWARE LIMITED PARTNERSHIP

                                       TO

                  PROXY STATEMENT/PROSPECTUS DATED       , 2001

                                   ----------

                   THE DATE OF THIS SUPPLEMENT IS       , 2001

                                   ----------


     This document contains important information specific to Parker & Parsley
91-B, L.P., and supplements the proxy statement/prospectus dated      , 2001, of
Pioneer Natural Resources Company and Pioneer Natural Resources USA, Inc., by
which Pioneer USA is soliciting proxies to be voted at a special meeting of
limited partners of the partnership. The purpose of the special meeting is for
you to vote upon the merger of the partnership with and into Pioneer USA that,
if completed, will result in your receiving common stock of Pioneer Natural
Resources Company for your partnership interests.


     This document contains the following information concerning Parker &
Parsley 91-B, L.P.:

     o    A table containing:

          --   the aggregate initial investment by the limited partners


          --   the aggregate historical limited partner distributions through
               July 31, 2001

          --   the merger value attributable to partnership interests of limited
               partners, excluding Pioneer USA

          --   the merger value per $1,000 limited partner investment

          --   the merger value per $1,000 limited partner investment as a
               multiple of distributions for the past four quarterly
               distributions including the distribution in July 2001


          --   the book value per $1,000 limited partner investment as of March
               31, 2001 and as of December 31, 2000


          --   the going concern value per $1,000 limited partner investment

          --   the liquidation value per $1,000 limited partner investment


          --   the ordinary tax loss per $1,000 limited partner investment in
               year of initial investment


     o    Information about:

          --   the legal opinion for the limited partners

          --   the term of the partnership


     o    The partnership's quarterly report on Form 10-Q, including
          management's discussion and analysis of financial condition and
          results of operations, for the three months ended March 31, 2001

     o    The partnership's annual report on Form 10-K, including management's
          discussion and analysis of financial condition and results of
          operations, for the year ended December 31, 2000

     o    Selected historical financial data for the partnership for the three
          months ended March 31, 2001 and 2000 and the five years ended December
          31, 2000

                                      -1-
   1710
                           PARKER & PARSLEY 91-B, L.P.

                         SUPPLEMENTAL INFORMATION TABLE


                                                                                           
Aggregate Initial Investment by the Limited Partners (a)                                      $  11,249

Aggregate Historical Limited Partner Distributions through July 31, 2001 (a)                  $   8,297

Merger Value Attributable to Partnership Interests of Limited Partners, Excluding Pioneer     $   4,976
USA (a), (b)

Merger Value per $1,000 Limited Partner Investment (b), (c)                                   $  442.73

Merger Value per $1,000 Limited Partner Investment as a Multiple of Distributions for the          3.71 times
past four quarterly distributions including the distribution in July 2001 (b), (c)

Book Value per $1,000 Limited Partner Investment:

          --  as of March 31, 2001 (c)                                                        $  155.30

          --  as of December 31, 2000 (c)                                                     $  160.69

Going Concern Value per $1,000 Limited Partner Investment (c), (d)                            $  415.14

Liquidation Value per $1,000 Limited Partner Investment (c), (e)                              $  429.56

Ordinary Tax Loss per $1,000 Limited Partner Investment in Year of Initial Investment         $     142
(c), (f)


----------

(a)  Stated in thousands.


(b)  The merger value for the partnership is equal to the sum of the present
     value of estimated future net revenues from the partnership's estimated oil
     and gas reserves and its net working capital, in each case as of March 31,
     2001, less its pro rata share, based on its reserve value, of the estimated
     expenses and fees of the mergers of all of the partnerships and less the
     cash distribution on or about July 9, 2001, by the partnership to its
     partners.

(c)  Interests in some partnerships were sold in units at prices other than
     $1,000. We have presented this information based on a $1,000 initial
     investment for ease of use and comparison among partnerships. You should
     not assume that the amount shown per $1,000 investment is the same as the
     value or amount attributable to a single unit investment.

(d)  The going concern value for the partnership is based upon: (1) the sum of
     (A) the estimated net cash flow from the sale of the partnership's reserves
     during a 10-year operating period and (B) the estimated residual value from
     the sale of the partnership's remaining reserves at the end of the
     operating period, in each case using the same pricing and discount rate as
     in the merger value calculation, less (2) partnership level general and
     administrative expenses.

(e)  The liquidation value for the partnership is based upon the sale of the
     partnership's reserves at the reserve value, less liquidation expenses
     which are estimated to be the sum of (1) the partnership's pro rata share
     of the merger expenses and fees described in footnote (b) above and (2) 3%
     of the partnership's reserve value. The liquidation expenses represent
     estimated costs to retain an investment banker or broker to sell the assets
     of the partnership and the legal and other closing costs associated with
     such transaction, including the wind-down costs of the partnership.

(f)  Your ability to use your distributive share of the partnership's loss to
     offset your other income may have been subject to certain limitations at
     your level as a partner, and you may therefore wish to consult your tax
     advisor to determine the additional value, if any, actually realized by you
     in your particular circumstances.


          INFORMATION ABOUT THE LEGAL OPINION FOR THE LIMITED PARTNERS

     The partnership agreement for the partnership requires that special legal
counsel render an opinion on behalf of the limited partners to Pioneer USA that
neither the grant nor the exercise of the right to approve the merger of the
partnership by its limited partners will adversely affect the federal income tax
classification of the partnership or any of its limited partners. Although not
required by the partnership agreement, the opinion will also state that neither
the grant nor exercise of such right will result in the loss of any limited
partner's limited liability. In addition, the counsel designated to render the
opinion is not required to be counsel other than counsel to Pioneer USA or the
partnership. Both the designated counsel and the legal opinion must be approved
by the limited partners. Pioneer USA has retained __________ of Dallas, Texas
for the purpose of rendering this legal opinion on behalf of the limited
partners to Pioneer USA. The merger proposals include an approval of that
counsel and the form of its opinion. A copy of the opinion is attached as an
exhibit to the merger proposals.


                  INFORMATION ABOUT THE TERM OF THE PARTNERSHIP

     The term of the partnership is until December 31, 2041, unless the
partnership is earlier terminated in accordance with the applicable provisions
of its partnership agreement.

                                      -2-

   1711

                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549


                                    FORM 10-Q


                Quarterly Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                  For the quarterly period ended March 31, 2001


                         Commission File No. 33-38582-02


                           PARKER & PARSLEY 91-B, L.P.
             (Exact name of Registrant as specified in its charter)

                   Delaware                            75-2397335
        -------------------------------          ----------------------
        (State or other jurisdiction of             (I.R.S. Employer
        incorporation or organization)           Identification Number)


1400 Williams Square West, 5205 N. O'Connor Blvd., Irving, Texas     75039
----------------------------------------------------------------   ----------
          (Address of principal executive offices)                 (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001

                                 Not applicable
              (Former name, former address and former fiscal year,
                          if changed since last report)


Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

                                 Yes [x] No [ ]



   1712

                           PARKER & PARSLEY 91-B, L.P.

                                TABLE OF CONTENTS




                                                                       Page
                          Part I. Financial Information
                                                                    
Item 1.    Financial Statements

           Balance Sheets as of March 31, 2001 and
              December 31, 2000......................................    3

           Statements of Operations for the three months
             ended March 31, 2001 and 2000...........................    4

           Statement of Partners' Capital for the three months
             ended March 31, 2001....................................    5

           Statements of Cash Flows for the three months
             ended March 31, 2001 and 2000...........................    6

           Notes to Financial Statements.............................    7

Item 2.    Management's Discussion and Analysis of Financial
             Condition and Results of Operations.....................    7


                           Part II. Other Information

Item 6.    Exhibits and Reports on Form 8-K..........................    9

           Signatures................................................   10




                                        2
   1713

                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                          Part 1. Financial Information

Item 1.       Financial Statements

                                 BALANCE SHEETS



                                                       March 31,     December 31,
                                                         2001            2000
                                                     ------------    ------------
                                                      (Unaudited)
              ASSETS
                                                               
Current assets:
  Cash                                               $    235,567    $    185,644
  Accounts receivable - oil and gas sales                 217,892         281,416
                                                     ------------    ------------
         Total current assets                             453,459         467,060
                                                     ------------    ------------
Oil and gas properties - at cost, based on the
  successful efforts accounting method                  9,763,077       9,761,207
Accumulated depletion                                  (8,420,591)     (8,398,807)
                                                     ------------    ------------
         Net oil and gas properties                     1,342,486       1,362,400
                                                     ------------    ------------
                                                     $  1,795,945    $  1,829,460
                                                     ============    ============
LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                       $     34,429    $      6,714

Partners' capital:
  Managing general partner                                 14,582          15,195
  Limited partners (11,249 interests)                   1,746,934       1,807,551
                                                     ------------    ------------
                                                        1,761,516       1,822,746
                                                     ------------    ------------
                                                     $  1,795,945    $  1,829,460
                                                     ============    ============



   The financial information included as of March 31,2001 has been prepared by
   the managing general partner without audit by independent public accountants.

     The accompanying notes are an integral part of these financial statements.


                                        3
   1714

                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                                   (Unaudited)




                                                Three months ended
                                                     March 31,
                                              -----------------------
                                                 2001         2000
                                              ----------   ----------
                                                     
Revenues:
  Oil and gas                                 $  381,877   $  453,588
  Interest                                         3,318        3,209
                                              ----------   ----------
                                                 385,195      456,797
                                              ----------   ----------
Costs and expenses:
  Oil and gas production                         124,783      145,956
  General and administrative                      17,982       11,204
  Depletion                                       21,784       21,965
                                              ----------   ----------
                                                 164,549      179,125
                                              ----------   ----------
Net income                                    $  220,646   $  277,672
                                              ==========   ==========
Allocation of net income:
  Managing general partner                    $    2,206   $    2,777
                                              ==========   ==========
  Limited partners                            $  218,440   $  274,895
                                              ==========   ==========
Net income per limited partnership interest   $    19.42   $    24.44
                                              ==========   ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        4
   1715
                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENT OF PARTNERS' CAPITAL
                                   (Unaudited)



                               Managing
                                general        Limited
                                partner        partners          Total
                             ------------    ------------    ------------
                                                    
Balance at January 1, 2001   $     15,195    $  1,807,551    $  1,822,746

    Distributions                  (2,819)       (279,057)       (281,876)

    Net income                      2,206         218,440         220,646
                             ------------    ------------    ------------

Balance at March 31, 2001    $     14,582    $  1,746,934    $  1,761,516
                             ============    ============    ============





         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        5
   1716

                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                          Three months ended
                                                               March 31,
                                                       ------------------------
                                                          2001          2000
                                                       ----------    ----------
                                                               
Cash flows from operating activities:
   Net income                                          $  220,646    $  277,672
   Adjustment to reconcile net income to net cash
     provided by operating activities:
        Depletion                                          21,784        21,965
   Changes in assets and liabilities:
        Accounts receivable                                63,524       (37,722)
        Accounts payable                                   27,715        (9,223)
                                                       ----------    ----------
           Net cash provided by operating activities      333,669       252,692
                                                       ----------    ----------
Cash flows from investing activities:
   Additions to oil and gas properties                     (2,003)       (5,869)
   Proceeds from dispositions of assets                       133            --
                                                       ----------    ----------
           Net cash used in investing activities           (1,870)       (5,869)
                                                       ----------    ----------
Cash flows used in financing activities:
   Cash distributions to partners                        (281,876)     (248,545)
                                                       ----------    ----------
Net increase (decrease) in cash                            49,923        (1,722)
Cash at beginning of period                               185,644       213,165
                                                       ----------    ----------
Cash at end of period                                  $  235,567    $  211,443
                                                       ==========    ==========




         The financial information included herein has been prepared by the
managing general partner without audit by independent public accountants.

The accompanying notes are an integral part of these financial statements.



                                        6
   1717

                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                                 March 31, 2001
                                   (Unaudited)

Note 1.     Organization and nature of operations

Parker & Parsley 91-B, L.P. (the "Partnership") is a limited partnership
organized in 1991 under the laws of the State of Delaware.

The Partnership engages in oil and gas development and production in Texas and
is not involved in any industry segment other than oil and gas.

Note 2.     Basis of presentation

In the opinion of management, the unaudited financial statements of the
Partnership as of March 31, 2001 include all adjustments and accruals consisting
only of normal recurring accrual adjustments which are necessary for a fair
presentation of the results for the interim period. These interim results are
not necessarily indicative of results for a full year. Certain reclassifications
may have been made to the March 31, 2000 financial statements to conform to the
March 31, 2001 financial statement presentations.

Certain information and footnote disclosures normally included in financial
statements prepared in accordance with generally accepted accounting principles
have been condensed or omitted in this Form 10-Q pursuant to the rules and
regulations of the Securities and Exchange Commission. The financial statements
should be read in conjunction with the financial statements and the notes
thereto contained in the Partnership's report on Form 10-K for the year ended
December 31, 2000, as filed with the Securities and Exchange Commission, a copy
of which is available upon request by writing to Rich Dealy, Vice President and
Chief Accounting Officer, 5205 North O'Connor Boulevard, 1400 Williams Square
West, Irving, Texas 75039-3746.

Item 2.     Management's Discussion and Analysis of Financial Condition
              and Results of Operations(1)

Results of Operations

Revenues:

The Partnership's oil and gas revenues decreased 16% to $381,877 for the three
months ended March 31, 2001 as compared to $453,588 for the same period in 2000.
The decrease in revenues resulted from a decrease in production, offset by
higher average prices received. For the three months ended March 31, 2001, 9,590
barrels of oil, 2,009 barrels of natural gas liquids ("NGLs") and 10,623 mcf of
gas were sold, or 13,370 barrel of oil equivalents ("BOEs"). For the three
months ended March 31, 2000, 12,062 barrels of oil, 4,976 barrels of NGLs and
19,802 mcf of gas were sold, or 20,338 BOEs.

                                        7

   1718

The average price received per barrel of oil increased slightly from $28.53 for
the three months ended March 31, 2000 to $28.83 for the same period in 2001. The
average price received per barrel of NGLs increased $3.34, or 22%, from $15.13
for the three months ended March 31, 2000 to $18.47 for the same period in 2001.
The average price received per mcf of gas increased 272% from $1.73 during the
three months ended March 31, 2000 to $6.43 for the same period in 2001. The
market price for oil and gas has been extremely volatile in the past decade, and
management expects a certain amount of volatility to continue in the foreseeable
future. The Partnership may therefore sell its future oil and gas production at
average prices lower or higher than that received during the three months ended
March 31, 2001.

Costs and Expenses:

Total costs and expenses decreased to $164,549 for the three months ended March
31, 2001 as compared to $179,125 for the same period in 2000, a decrease of
$14,576, or 8%. This decrease was primarily due to declines in production costs
and depletion, offset by an increase in general and administrative expenses
("G&A").

Production costs were $124,783 for the three months ended March 31, 2001 and
$145,956 for the same period in 2000, resulting in a $21,173 decrease, or 15%.
The decrease was primarily due to lower well maintenance and workover costs.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and administrative costs. During this period, G&A
increased 60% from $11,204 for the three months ended March 31, 2000 to $17,982
for the same period in 2001, primarily due to an increase in the accrual for tax
preparation and monitoring service fees.

Depletion was $21,784 for the three months ended March 31, 2001 as compared to
$21,965 for the same period in 2000, a decrease of $181, or 1%. The decrease was
primarily due to a decrease in oil production of 2,472 barrels for the period
ended March 31, 2001 compared to the same period in 2000, offset by a downward
revision to one well's proved reserves during the three months ended March 31,
2001.

Liquidity and Capital Resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $80,977 during the three
months ended March 31, 2001 from the same period ended March 31, 2000. The
increase was primarily attributable to reductions of $138,184 in working capital
and production costs of $21,173, offset by a decline in oil and gas sales
receipts of $71,602 and an increase in G&A expenses of $6,778. The decrease in
production costs was primarily due to lower well maintenance and workover costs.
The decrease in oil and gas receipts resulted from $185,099 from the decline in
production during 2001, offset by $113,497 from the increase in commodity prices
during 2001. The increase in G&A was primarily due to an increase in the accrual
for tax preparation and monitoring service fees.


                                        8
   1719

Net Cash Used in Investing Activities

The Partnership's investing activities during the three months ended March 31,
2001 and 2000 were related to the upgrades of oil and gas equipment on active
properties.

Proceeds from disposition of assets of $133 recognized during the three months
ended March 31, 2001 were related to equipment credits on one active well.

Net Cash Used in Financing Activities

For the three months ended March 31, 2001, cash distributions to the partners
were $281,876, of which $2,819 was distributed to the managing general partner
and $279,057 to the limited partners. For the same period ended March 31, 2000,
cash distributions to the partners were $248,545, of which $2,485 was
distributed to the managing general partner and $246,060 to the limited
partners.

Proposal to acquire partnerships

On April 17, 2001, Pioneer Natural Resources Company ("Pioneer") filed a
preliminary proxy statement/prospectus with the Securities and Exchange
Commission proposing an agreement and plan of merger among Pioneer, Pioneer
Natural Resources USA, Inc. ("Pioneer USA"), a wholly-owned subsidiary of
Pioneer, and the limited partners of 46 Parker & Parsley limited partnerships.
Each partnership that approves the agreement and plan of merger and the other
related merger proposals will merge with and into Pioneer USA, and the
partnership interests of each such partnership will be converted into the right
to receive cash and Pioneer common stock. Pioneer USA is the sole or managing
general partner of the partnerships. The Partnership is one of the 46 Parker &
Parsley limited partnerships being requested to approve the agreement and plan
of merger. The preliminary proxy statement/prospectus is non-binding and is
subject to, among other things, consideration of offers from third parties to
purchase any partnership or its assets, requires 66-2/3% approval of the limited
partnership interests in each partnership and the resolution of Securities and
Exchange Commission review comments. No solicitation will be made using
preliminary materials.

----------

(1)  "Item 2. Management's Discussion and Analysis of Financial Condition and
     Results of Operations" contains forward looking statements that involve
     risks and uncertainties. Accordingly, no assurances can be given that the
     actual events and results will not be materially different than the
     anticipated results described in the forward looking statements.


                           Part II. Other Information

Item 6.     Exhibits and Reports on Form 8-K

     (a)   Exhibits - none

     (b)   Reports on Form 8-K - none.



                                        9
   1720

                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)


                                   SIGNATURES


       Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.


                                            PARKER & PARSLEY 91-B, L.P.


                                    By:     Pioneer Natural Resources USA, Inc.
                                             Managing General Partner



Dated:  May 14, 2001                By:     /s/ Rich Dealy
                                            ----------------------------------
                                            Rich Dealy, Vice President
                                              and Chief Accounting Officer




                                       10
   1721
                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D. C. 20549

                                    FORM 10-K

                  Annual Report Pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934

                   FOR THE FISCAL YEAR ENDED DECEMBER 31, 2000


                         COMMISSION FILE NO. 33-38582-02


                           PARKER & PARSLEY 91-B, L.P.
             (Exact name of Registrant as specified in its charter)

         DELAWARE                                          75-2397335
--------------------------------------               ----------------------
(State or other jurisdiction of                        (I.R.S. Employer
incorporation or organization)                      Identification Number)



                                                                                   
1400 WILLIAMS SQUARE WEST, 5205 N. O'CONNOR BLVD., IRVING, TEXAS                        75039
----------------------------------------------------------------                      -------------
          (Address of principal executive offices)                                     (Zip code)


       Registrant's Telephone Number, including area code : (972) 444-9001


        Securities registered pursuant to Section 12(b) of the Act: NONE
           Securities registered pursuant to Section 12(g) of the Act:
                 LIMITED PARTNERSHIP INTERESTS ($1,000 PER UNIT)

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the Registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. YES / X / NO / /

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of Registrant's knowledge, in definitive proxy or information statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. / X /

No market currently exists for the limited partnership interests of the
Registrant. Based on the original purchase price, the aggregate market value of
limited partnership interests owned by non-affiliates of the Registrant is
$11,239,000.

      As of March 8, 2001, the number of outstanding limited partnership
interests was 11,249.

 The following documents are incorporated by reference into the indicated parts
                    of this Annual Report on Form 10-K: None


PARTS I AND II OF THIS ANNUAL REPORT ON FORM 10-K (THE "REPORT") CONTAIN FORWARD
LOOKING STATEMENTS THAT INVOLVE RISKS AND UNCERTAINTIES. ACCORDINGLY, NO
ASSURANCES CAN BE GIVEN THAT THE ACTUAL EVENTS AND RESULTS WILL NOT BE
MATERIALLY DIFFERENT THAN THE ANTICIPATED RESULTS DESCRIBED IN THE FORWARD
LOOKING STATEMENTS. SEE "ITEM 1. BUSINESS" FOR A DESCRIPTION OF VARIOUS FACTORS
THAT COULD MATERIALLY AFFECT THE ABILITY OF THE PARTNERSHIP TO ACHIEVE THE
ANTICIPATED RESULTS DESCRIBED IN THE FORWARD LOOKING STATEMENTS.
   1722



                                     PART I

ITEM 1.    BUSINESS

Parker & Parsley 91-B, L.P. (the "Partnership") is a limited partnership
organized in 1991 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").
Pioneer USA is a wholly-owned subsidiary of Pioneer Natural Resources Company
("Pioneer"). As of March 8, 2001, the Partnership had 11,249 limited partnership
interests outstanding.

The Partnership does not have any employees of its own. Pioneer USA employs 701
persons, many of whom dedicated a part of their time to the conduct of the
Partnership's business during the period for which this Report is filed. Pioneer
USA is responsible for all management functions.

The Partnership engages in oil and gas development and production and is not
involved in any industry segment other than oil and gas. The Partnership's
production is geographically concentrated in West Texas.

The principal markets during 2000 for the oil produced by the Partnership were
refineries and oil transmission companies that have facilities near the
Partnership's oil producing properties. During 2000, Pioneer USA marketed the
Partnership's gas to a variety of purchasers, none of which accounted for 10% or
more of the Partnership's oil and gas revenues. Of the Partnership's total oil
and gas revenues for 2000, approximately 48% and 22% were attributable to sales
made to Mobil Oil Corporation and Plains Marketing, L.P., respectively. Pioneer
USA is of the opinion that the loss of any one purchaser would not have an
adverse effect on its ability to sell its oil, natural gas liquids ("NGLs") and
gas production.

The Partnership's revenues, profitability, cash flow and future rate of growth
are highly dependent on the prevailing prices of oil and gas, which are affected
by numerous factors beyond the Partnership's control. Oil and gas prices
historically have been very volatile. A substantial or extended decline in the
prices of oil or gas could have a material adverse effect on the Partnership's
revenues, profitability and cash flow and could, under certain circumstances,
result in a reduction in the carrying value of the Partnership's oil and gas
properties.

Oil and gas production operations are subject to various types of regulations by
local, state and federal agencies. The Partnership's operations are also subject
to state conservation laws and regulations, including the establishment of
maximum rates of production from wells and the regulation of spacing, plugging
and abandonment of wells. Each state generally imposes a production or severance
tax with respect to production and sale of oil and gas within their respective
jurisdictions. Noncompliance with the laws and regulations may subject the
Partnership to penalties, damages or other liabilities and compliance may
increase the cost of the Partnership's operations.
The oil and gas business is also subject to environmental hazards such as oil
spills, gas leaks and ruptures and discharges of toxic substances or gases that
could expose the Partnership to substantial



                                       2
   1723

liability due to pollution and other environmental damages. Although the
Partnership believes that its business operations do not impair environmental
quality and that its costs of complying with any applicable environmental
regulations are not currently significant, the Partnership cannot predict what,
if any, effect these environmental regulations may have on its current or future
operations.

Numerous uncertainties exist in estimating quantities of proved reserves and
future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves.

No material part of the Partnership's business is seasonal and the Partnership
conducts no foreign operations.

ITEM 2. PROPERTIES

The Partnership's properties consist of leasehold interests in properties on
which oil and gas wells are located. Such property interests are often subject
to landowner royalties, overriding royalties and other oil and gas leasehold
interests.

Fractional working interests in developmental oil and gas prospects located
primarily in the Spraberry Trend Area of West Texas were acquired by the
Partnership, resulting in the Partnership's participation in the drilling of 29
oil and gas wells. At December 31, 2000, the Partnership had 29 producing oil
and gas wells.

For information relating to the Partnership's estimated proved oil and gas
reserves at December 31, 2000, 1999 and 1998, see Note 7 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data"
below. Such reserves have been evaluated by Williamson Petroleum Consultants,
Inc., an independent petroleum consultant.

ITEM 3. LEGAL PROCEEDINGS

The Partnership from time to time is a party to various legal proceedings
incidental to its business involving claims in oil and gas leases or interests,
other claims for damages in amounts not in excess of 10% of its current assets
and other matters, none of which Pioneer USA believes to be material to the
Partnership.

ITEM 4. SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

There were no matters submitted to a vote of the partners during the fourth
quarter of 2000.







                                       3
   1724


                                     PART II


ITEM 5.   MARKET FOR LIMITED PARTNERSHIP INTERESTS AND LIMITED PARTNERSHIP
          DISTRIBUTIONS

At March 8, 2001, the Partnership had 11,249 outstanding limited partnership
interests held of record by 677 subscribers. There is no established public
trading market for the limited partnership interests. Under the limited
partnership agreement, Pioneer USA has made certain commitments to purchase
partnership interests at a computed value.

Revenues which, in the sole judgement of the managing general partner, are not
required to meet the Partnership's obligations will be distributed to the
partners at least quarterly in accordance with the limited partnership
agreement. During the years ended December 31, 2000 and 1999, $1,324,583 and
$481,274, respectively, of such revenue-related distributions were made to the
limited partners.

ITEM 6.   SELECTED FINANCIAL DATA

The following table sets forth selected financial data for the years ended
December 31:



                                       2000            1999             1998             1997         1996
                                 --------------   -------------   --------------   --------------   ----------
                                                                                     
Operating results:
-------------------
  Oil and gas sales              $    2,046,224   $   1,136,073   $      873,012   $    1,273,373   $1,632,595
                                 ==============   =============   ==============   ==============   ==========

  Impairment of oil and gas
     properties                  $           --   $          --   $      295,542   $      323,078   $       --
                                 ==============   =============   ==============   ==============   ==========

  Net income (loss)              $    1,354,094   $     490,669   $     (177,905)  $      222,730   $  924,002
                                 ==============   =============   ==============   ==============   ==========

  Allocation of net income
    (loss):
      Managing general partner   $       13,541   $       4,907   $       (1,779)  $        2,227   $    9,240
                                 ==============   =============   ==============   ==============   ==========

      Limited partners           $    1,340,553   $     485,762   $     (176,126)  $      220,503   $  914,762
                                 ==============   =============   ==============   ==============   ==========

  Limited partners' net
     income (loss) per limited
     partnership interest        $       119.17   $       43.18   $       (15.66)  $        19.60   $    81.32
                                 ==============   =============   ==============   ==============   ==========

  Limited partners' cash
     distributions per limited
     partnership interest        $       117.75   $       42.78   $        36.76   $        75.32   $    84.40
                                 ==============   =============   ==============   ==============   ==========

At year end:
-------------
  Identifiable assets            $    1,829,460   $   1,843,803   $    1,820,336   $    2,424,808   $3,051,464
                                 ==============   =============   ==============   ==============   ==========








                                       4
   1725


ITEM 7. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND
         RESULTS OF OPERATIONS

Results of Operations

2000 compared to 1999

The Partnership's oil and gas revenues increased 80% to $2,046,224 for 2000 as
compared to $1,136,073 in 1999. The increase in revenues resulted from higher
average prices received and an increase in production. In 2000, 47,684 barrels
of oil, 21,866 barrels of natural gas liquids ("NGLs") and 85,556 mcf of gas
were sold, or 83,809 barrel of oil equivalents ("BOEs"). In 1999, 46,030 barrels
of oil, 19,026 barrels of NGLs and 74,025 mcf of gas were sold, or 77,394 BOEs.
Due to the decline characteristics of the Partnership's oil and gas properties,
management expects a certain amount of decline in production in the future until
the Partnership's economically recoverable reserves are fully depleted.

The average price received per barrel of oil increased $12.19, or 68%, from
$17.90 in 1999 to $30.09 in 2000. The average price received per barrel of NGLs
increased $6.35, or 63%, from $10.15 in 1999 to $16.50 in 2000. The average
price received per mcf of gas increased 82% from $1.61 in 1999 to $2.93 in 2000.
The market price for oil and gas has been extremely volatile in the past decade
and management expects a certain amount of volatility to continue in the
foreseeable future. The Partnership may therefore sell its future oil and gas
production at average prices lower or higher than that received in 2000.

Gain on disposition of assets of $2,273 was recognized during 2000 from
equipment credits received on one fully depleted well.

Total costs and expenses increased in 2000 to $713,527 as compared to $655,625
in 1999, an increase of $57,902, or 9%. The increase was due to an increase in
production costs, offset by decreases in depletion and general and
administrative expenses ("G&A").

Production costs were $576,561 in 2000 and $442,342 in 1999, resulting in an
increase of $134,219, or 30%. This increase was primarily due to higher
production taxes associated with higher oil and gas prices and additional well
maintenance and workover costs incurred to stimulate well production.

G&A's components are independent accounting and engineering fees and managing
general partner personnel and operating costs. During this period, G&A decreased
22% from $68,860 in 1999 to $53,623 in 2000. The Partnership paid the managing
general partner $38,999 in 2000 and $33,982 in 1999 for G&A incurred on behalf
of the Partnership. The remaining G&A was paid directly by the Partnership. The
managing general partner determines the allocated expenses based upon the level
of activity of the Partnership relative to the non-partnership activities of the
managing general partner. The method of allocation has been consistent over the
past several years with certain modifications incorporated to reflect changes in
Pioneer USA's overall business activities.

Depletion was $83,343 in 2000 as compared to $144,423 in 1999, representing a
decrease of $61,080, or 42%. This decrease was primarily due to a 82,084 barrels
of oil increase in proved reserves during 2000 as a result of higher commodity
prices.



                                       5
   1726


1999 compared to 1998

The Partnership's 1999 oil and gas revenues increased 30% to $1,136,073 from
$873,012 in 1998. The increase in revenues resulted from higher average prices
received, offset by a decline in production. In 1999, 46,030 barrels of oil,
19,026 barrels of NGLs and 74,025 mcf of gas were sold, or 77,394 BOEs. In 1998,
49,100 barrels of oil, 17,427 barrels of NGLs and 68,244 mcf of gas were sold,
or 77,901 BOEs.

The average price received per barrel of oil increased $4.57, or 34%, from
$13.33 in 1998 to $17.90 in 1999. The average price received per barrel of NGLs
increased $3.36, or 49%, from $6.79 in 1998 to $10.15 in 1999. The average price
received per mcf of gas increased 10% from $1.47 in 1998 to $1.61 in 1999.

Gain on disposition of assets of $197 recognized in 1998 was attributable to
credits received from the disposal of oil and gas equipment on a saltwater
disposal well that was plugged and abandoned in a prior year.

Total costs and expenses decreased in 1999 to $655,625 as compared to $1,062,299
in 1998, a decrease of $406,674, or 38%. The decrease was due to declines in the
impairment of oil and gas properties, depletion and production costs, offset by
an increase in G&A.

Production costs were $442,342 in 1999 and $464,489 in 1998, resulting in a
$22,147 decrease, or 5%. This decrease was due to lower ad valorem taxes and
well maintenance costs, offset by an increase in production taxes due to
increased oil and gas revenues.

During this period, G&A increased 58% from $43,606 in 1998 to $68,860 in 1999
primarily due to a higher percentage of the managing general partner's G&A being
allocated (limited to 3% of oil and gas revenues) as a result of increased oil
and gas revenues. The Partnership paid the managing general partner $33,982 in
1999 and $27,503 in 1998 for G&A incurred on behalf of the Partnership.

In accordance with Statement of Financial Accounting Standards No. 121,
"Accounting for the Impairment of Long-Lived Assets and for Long-Lived Assets to
be Disposed Of" ("SFAS 121"), the managing general partner reviews the
Partnership's oil and gas properties for impairment whenever events or
circumstances indicate a decline in the recoverability of the carrying value of
the Partnership's assets may have occurred. As a result of the review and
evaluation of its long-lived assets for impairment, the Partnership recognized a
non-cash charge of $295,542 related to its oil and gas properties during 1998.

Depletion was $144,423 in 1999 compared to $258,662 in 1998. This represented a
decrease of $114,239, or 44%. This decrease was primarily the result of an
increase in proved reserves of 362,706 barrels of oil during 1999 as a result of
higher commodity prices, a reduction in the Partnership's net depletable basis
from charges taken in accordance with SFAS 121 during the fourth quarter of
1998.







                                       6
   1727


Petroleum industry

The petroleum industry has been characterized by volatile oil, NGL and natural
gas commodity prices and relatively stable supplier costs during the three years
ended December 31, 2000. During 1998, weather patterns, regional economic
recessions and political matters combined to cause worldwide oil supplies to
exceed demand resulting in a substantial decline in oil prices. Also during
1998, but to a lesser extent, market prices for natural gas declined. During
1999 and 2000, the Organization of Petroleum Exporting Countries ("OPEC") and
certain other crude oil exporting nations announced reductions in their planned
export volumes. Those announcements, together with the enactment of the
announced reductions in export volumes, had a positive impact on world oil
prices, as have overall natural gas supply and demand fundamentals on North
American natural gas prices. Although the favorable commodity price environment
and stable field service cost environment is expected to continue during 2001,
there is no assurance that commodity prices will not return to a less favorable
level or that field service costs will not escalate in the future, both of which
could negatively impact the Partnership's future results of operations and cash
distributions.

Liquidity and capital resources

Net Cash Provided by Operating Activities

Net cash provided by operating activities increased $766,498 during the year
ended December 31, 2000 from 1999. This increase was due to an increase in oil
and gas sales receipts of $919,054 and a decline in G&A expenses paid of
$15,237, offset by increases in production costs paid of $134,219 and working
capital of $33,574. The increase in oil and gas receipts resulted from the
increase in commodity prices during 2000 which contributed an additional
$788,626 to oil and gas receipts and $130,428 resulting from the increase in
production during 2000. The increase in production costs was primarily due to
increased production taxes associated with higher oil and gas prices and
additional well maintenance and workover costs incurred to stimulate well
production.

Net Cash Used in Investing Activities

The Partnership's principal investing activities during 2000 and 1999 were
related to the addition of equipment on various oil and gas properties.

Proceeds from asset dispositions of $2,372 recognized during 2000 were related
to equipment credits on two active wells.

Net Cash Used in Financing Activities

In 2000, cash distributions to the partners were $1,337,963, of which $13,380
was distributed to the managing general partner and $1,324,583 to the limited
partners. In 1999, cash distributions to the partners were $486,135, of which
$4,861 was distributed to the managing general partner and $481,274 to the
limited partners.




                                       7
   1728


ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

                          INDEX TO FINANCIAL STATEMENTS



                                                                                                           Page
                                                                                                           ----
                                                                                                        
Financial Statements of Parker & Parsley 91-B, L.P.:
  Independent Auditors' Report........................................................................         9
  Balance Sheets as of December 31, 2000 and 1999.....................................................        10
  Statements of Operations for the Years Ended December 31,
    2000, 1999 and 1998...............................................................................        11
  Statements of Partners' Capital for the Years Ended
    December 31, 2000, 1999 and 1998..................................................................        12
  Statements of Cash Flows for the Years Ended December 31,
    2000, 1999 and 1998...............................................................................        13
  Notes to Financial Statements.......................................................................        14





                                       8
   1729







                          INDEPENDENT AUDITORS' REPORT



The Partners
Parker & Parsley 91-B, L.P.
  (A Delaware Limited Partnership):

We have audited the balance sheets of Parker & Parsley 91-B, L.P. as of December
31, 2000 and 1999, and the related statements of operations, partners' capital
and cash flows for each of the three years in the period ended December 31,
2000. These financial statements are the responsibility of the Partnership's
management. Our responsibility is to express an opinion on these financial
statements based on our audits.

We conducted our audits in accordance with auditing standards generally accepted
in the United States. Those standards require that we plan and perform the audit
to obtain reasonable assurance about whether the financial statements are free
of material misstatement. An audit includes examining, on a test basis, evidence
supporting the amounts and disclosures in the financial statements. An audit
also includes assessing the accounting principles used and significant estimates
made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our
opinion.

In our opinion, the financial statements referred to above present fairly, in
all material respects, the financial position of Parker & Parsley 91-B, L.P. as
of December 31, 2000 and 1999, and the results of its operations and its cash
flows for each of the three years in the period ended December 31, 2000, in
conformity with accounting principles generally accepted in the United States.




                                             Ernst & Young LLP

Dallas, Texas
March 9, 2001




                                       9
   1730


                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                                 BALANCE SHEETS
                                   December 31





                                                                          2000                   1999
                                                                    ----------------       ----------------
                     ASSETS

Current assets:
                                                                                     
  Cash                                                              $       185,644        $       213,165
  Accounts receivable - oil and gas sales                                   281,416                197,204
                                                                      -------------          -------------

            Total current assets                                            467,060                410,369
                                                                      -------------          -------------

Oil and gas properties - at cost, based on the
  successful efforts accounting method                                    9,761,207              9,748,898
Accumulated depletion                                                    (8,398,807)            (8,315,464)
                                                                      -------------          -------------

            Net oil and gas properties                                    1,362,400              1,433,434
                                                                      -------------          -------------

                                                                    $     1,829,460        $     1,843,803
                                                                     ==============         ==============


LIABILITIES AND PARTNERS' CAPITAL

Current liabilities:
  Accounts payable - affiliate                                      $         6,714        $        37,188

Partners' capital:
  Managing general partner                                                   15,195                 15,034
  Limited partners (11,249 interests)                                     1,807,551              1,791,581
                                                                      -------------          -------------

                                                                          1,822,746              1,806,615
                                                                      -------------          -------------

                                                                    $     1,829,460        $     1,843,803
                                                                     ==============         ==============
















   The accompanying notes are an integral part of these financial statements.




                                       10
   1731


                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF OPERATIONS
                         For the years ended December 31






                                                         2000          1999          1998
                                                     -----------   -----------   -----------
                                                                        
Revenues:
  Oil and gas                                        $ 2,046,224   $ 1,136,073   $   873,012
  Interest                                                19,124        10,221        11,185
  Gain on disposition of assets                            2,273            --           197
                                                     -----------   -----------   -----------

                                                       2,067,621     1,146,294       884,394
                                                     -----------   -----------   -----------

Costs and expenses:
  Oil and gas production                                 576,561       442,342       464,489
  General and administrative                              53,623        68,860        43,606
  Impairment of oil and gas properties                        --            --       295,542
  Depletion                                               83,343       144,423       258,662
                                                     -----------   -----------   -----------

                                                         713,527       655,625     1,062,299
                                                     -----------   -----------   -----------

Net income (loss)                                    $ 1,354,094   $   490,669   $  (177,905)
                                                     ===========   ===========   ===========

Allocation of net income (loss):
  Managing general partner                           $    13,541   $     4,907   $    (1,779)
                                                     ===========   ===========   ===========

  Limited partners                                   $ 1,340,553   $   485,762   $  (176,126)
                                                     ===========   ===========   ===========

Net income (loss) per limited partnership interest   $    119.17   $     43.18   $    (15.66)
                                                     ===========   ===========   ===========








   The accompanying notes are an integral part of these financial statements.



                                       11
   1732


                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                         STATEMENTS OF PARTNERS' CAPITAL






                                                               Managing
                                                                general              Limited
                                                                partner              partners               Total
                                                            --------------        --------------       ----------------


                                                                                              
Partners' capital at January 1, 1998                        $      20,944         $   2,376,754        $    2,397,698

    Distributions                                                  (4,177)             (413,535)             (417,712)

    Net loss                                                       (1,779)             (176,126)             (177,905)
                                                              -----------           -----------          ------------

Partners' capital at December 31, 1998                             14,988             1,787,093             1,802,081

    Distributions                                                  (4,861)             (481,274)             (486,135)

    Net income                                                      4,907               485,762               490,669
                                                              -----------           -----------          ------------

Partners' capital at December 31, 1999                             15,034             1,791,581             1,806,615

    Distributions                                                 (13,380)           (1,324,583)           (1,337,963)

    Net income                                                     13,541             1,340,553             1,354,094
                                                              -----------           -----------          ------------

Partners' capital at December 31, 2000                      $      15,195         $   1,807,551        $    1,822,746
                                                             ============          ============         =============






















   The accompanying notes are an integral part of these financial statements.



                                       12
   1733


                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                            STATEMENTS OF CASH FLOWS
                         For the years ended December 31




                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------
                                                                                                         
Cash flows from operations:
   Net income (loss)                                                    $   1,354,094        $     490,669        $    (177,905)
   Adjustments to reconcile net income (loss)
      to net cash provided by operating activities:
        Impairment of oil and gas properties                                      -                    -                295,542
        Depletion                                                              83,343              144,423              258,662
        Gain on disposition of assets                                          (2,273)                 -                   (197)
   Changes in assets and liabilities:
        Accounts receivable                                                   (84,212)            (100,045)              39,758
        Accounts payable                                                      (30,474)              18,933               (8,855)
                                                                          -----------          -----------          -----------

            Net cash provided by operating activities                       1,320,478              553,980              407,005
                                                                          -----------          -----------          -----------

Cash flows from investing activities:
   Additions to oil and gas properties                                        (12,408)             (19,911)             (24,381)
   Proceeds from asset dispositions                                             2,372                  -                    197
                                                                          -----------          -----------          -----------

            Net cash used in investing activities                             (10,036)             (19,911)             (24,184)
                                                                          -----------          -----------          -----------

Cash flows used in financing activities:
   Cash distributions to partners                                          (1,337,963)            (486,135)            (417,712)
                                                                          -----------          -----------          -----------

Net increase (decrease) in cash                                               (27,521)              47,934              (34,891)
Cash at beginning of year                                                     213,165              165,231              200,122
                                                                          -----------          -----------          -----------

Cash at end of year                                                     $     185,644        $     213,165        $     165,231
                                                                         ============         ============         ============











   The accompanying notes are an integral part of these financial statements.



                                       13
   1734


                           PARKER & PARSLEY 91-B, L.P.
                        (A Delaware Limited Partnership)

                          NOTES TO FINANCIAL STATEMENTS
                        December 31, 2000, 1999 and 1998

NOTE 1. ORGANIZATION AND NATURE OF OPERATIONS

      Parker & Parsley 91-B, L.P. (the "Partnership") is a limited partnership
organized in 1991 under the laws of the State of Delaware. The Partnership's
managing general partner is Pioneer Natural Resources USA, Inc. ("Pioneer USA").

      The Partnership engages in oil and gas development and production in Texas
and is not involved in any industry segment other than oil and gas.

NOTE 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

      A summary of the significant accounting policies consistently applied in
the preparation of the accompanying financial statements follows:

      Oil and gas properties - The Partnership utilizes the successful efforts
method of accounting for its oil and gas properties and equipment. Under this
method, all costs associated with productive wells and nonproductive development
wells are capitalized while nonproductive exploration costs are expensed.
Capitalized costs relating to proved properties are depleted using the
unit-of-production method on a property-by-property basis based on proved oil
(dominant mineral) reserves as evaluated by independent petroleum consultants.
The carrying amounts of properties sold or otherwise disposed of and the related
allowances for depletion are eliminated from the accounts and any gain or loss
is included in results of operations.

      Impairment of long-lived assets - In accordance with Statement of
Financial Accounting Standards No. 121, "Accounting for the Impairment of
Long-Lived Assets and for Long-Lived Assets to be Disposed Of" ("SFAS 121"), the
Partnership reviews its long-lived assets to be held and used on an individual
property basis, including oil and gas properties accounted for under the
successful efforts method of accounting, whenever events or circumstances
indicate that the carrying value of those assets may not be recoverable. An
impairment loss is indicated if the sum of the expected future cash flows is
less than the carrying amount of the assets. In this circumstance, the
Partnership recognizes an impairment loss for the amount by which the carrying
amount of the asset exceeds the estimated fair value of the asset.

      Use of estimates in the preparation of financial statements - Preparation
of the accompanying financial statements in conformity with generally accepted
accounting principles requires management to make estimates and assumptions that
affect the reported amounts of assets and liabilities and disclosure of
contingent assets and liabilities at the date of the financial statements and
the reported amounts of revenues and expenses during the reporting periods.
Actual results could differ from those estimates.


        Net income (loss) per limited partnership interest - The net income
(loss) per limited partnership interest is calculated by using the number of
outstanding limited partnership interests.

        Income taxes - A Federal income tax provision has not been included in
the financial statements as the income of the Partnership is included in the
individual Federal income tax returns of the respective partners.



                                       14
   1735

        Statements of cash flows - For purposes of reporting cash flows, cash
includes depository accounts held by banks.

        General and administrative expenses - General and administrative
expenses are allocated in part to the Partnership by the managing general
partner. Allocated expenses are determined by the managing general partner based
upon the level of activity of the Partnership relative to the non-partnership
activities of the managing general partner. The method of allocation has been
consistent over the past several years with certain modifications incorporated
to reflect changes in Pioneer USA's overall business activities.

        Reclassifications - Certain reclassifications may have been made to the
1999 and 1998 financial statements to conform to the 2000 financial statement
presentations.

        Environmental - The Partnership is subject to extensive federal, state
and local environmental laws and regulations. These laws, which are constantly
changing, regulate the discharge of materials into the environment and may
require the Partnership to remove or mitigate the environmental effects of the
disposal or release of petroleum or chemical substances at various sites.
Environmental expenditures are expensed or capitalized depending on their future
economic benefit. Expenditures that relate to an existing condition caused by
past operations and that have no future economic benefits are expensed.
Liabilities for expenditures of a noncapital nature are recorded when
environmental assessment and/or remediation is probable, and the costs can be
reasonably estimated. Such liabilities are generally undiscounted unless the
timing of cash payments for the liability or component are fixed or reliably
determinable. No such liabilities have been accrued as of December 31, 2000.

        Revenue recognition - The Partnership uses the entitlements method of
accounting for oil, natural gas liquids ("NGLs") and natural gas revenues.

NOTE 3. IMPAIRMENT OF LONG-LIVED ASSETS

        In accordance with SFAS 121, the Partnership reviews its proved oil and
gas properties for impairment whenever events and circumstances indicate a
decline in the recoverability of the carrying value of the Partnership's oil and
gas properties. The Partnership has estimated the expected future cash flows of
its oil and gas properties as of December 31, 2000, 1999 and 1998, based on
proved reserves, and compared such estimated future cash flows to the respective
carrying amount of the oil and gas properties to determine if the carrying
amounts were likely to be recoverable. For those proved oil and gas properties
for which the carrying amount exceeded the estimated future cash flows, an
impairment was determined to exist; therefore, the Partnership adjusted the
carrying amount of those oil and gas properties to their fair value as
determined by discounting their expected future cash flows at a discount rate
commensurate with the risks involved in the industry. As a result, the
Partnership recognized a non-cash impairment provision of $295,542 related to
its proved oil and gas properties during 1998.



                                       15
   1736

NOTE 4. INCOME TAXES

        The financial statement basis of the Partnership's net assets and
liabilities was $367,378 greater than the tax basis at December 31, 2000.

        The following is a reconciliation of net income (loss) per statements of
operations with the net income (loss) per Federal income tax returns for the
years ended December 31:



                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                         
   Net income (loss) per statements of operations                       $    1,354,094       $     490,669        $    (177,905)
   Depletion and depreciation provisions for tax
     reporting purposes greater than amounts for
     financial reporting purposes                                              (27,307)           (115,006)            (139,323)
   Impairment of oil and gas properties for financial
     reporting purposes                                                            -                   -                295,542
   Salvage income                                                                                      -                    -
   Intangible development costs capitalized for
     financial reporting purposes and expensed
     for tax reporting purposes                                                   (328)                -                    -
   Other, net                                                                   (2,832)             (4,142)               4,532
                                                                          ------------         -----------          -----------
            Net income (loss) per Federal income
              tax returns                                               $    1,323,627       $     371,521        $     (17,154)
                                                                         =============        ============         ============


NOTE 5. OIL AND GAS PRODUCING ACTIVITIES

        The following is a summary of the net costs incurred, whether
capitalized or expensed, related to the Partnership's oil and gas producing
activities for the years ended December 31:



                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                         
        Development costs                                               $       12,408       $      19,911        $      24,381
                                                                         =============        ============         ============


        Capitalized oil and gas properties consist of the following:


                                                                                              2000                      1999
                                                                                        ----------------          ----------------

                                                                                                           
     Property acquisition costs                                                         $       949,486          $       949,486
     Completed wells and equipment                                                            8,811,721                8,799,412
                                                                                          -------------            -------------

                                                                                              9,761,207                9,748,898
           Accumulated depletion                                                             (8,398,807)              (8,315,464)
                                                                                          -------------            -------------

                  Net oil and gas properties                                            $     1,362,400          $     1,433,434
                                                                                         ==============           ==============


NOTE 6. RELATED PARTY TRANSACTIONS

        Pursuant to the limited partnership agreement, the Partnership had the
following related party transactions with the managing general partner during
the years ended December 31:



                                       16
   1737






                                                                             2000                 1999                 1998
                                                                        --------------       --------------       --------------

                                                                                                         
       Payment of lease operating and supervision
          charges in accordance with standard
          industry operating agreements                                 $      196,507       $     189,784        $     182,097

       Reimbursement of general and administrative
          expenses                                                      $       38,999       $      33,982        $      27,503


        The Partnership participates in oil and gas activities through an income
tax partnership (the "Program") pursuant to the Program agreement. Pioneer USA,
P&P Employees 91-B GP ("EMPL") and the Partnership are parties to the Program
agreement. EMPL is a general partnership organized for the benefit of certain
employees of Pioneer USA. EMPL was merged with Pioneer USA on December 28, 2000.

        The costs and revenues of the Program are allocated to Pioneer USA and
the Partnership as follows:



                                                                                        Pioneer USA (1)           Partnership (1)
                                                                                        ---------------           ---------------
                                                                                                         
        Revenues:
          Proceeds from disposition of depreciable and
            depletable properties                                                          34.3434343%             65.6565657%
          All other revenues                                                               34.3434343%             65.6565657%

        Costs and expenses:
          Lease acquisition costs, drilling and completion
            costs and all other costs                                                      24.2424242%             75.7575758%
          Operating costs, reporting and legal expenses and
            general and administrative expenses                                            34.3434343%             65.6565657%


      (1)   Includes Pioneer USA's 1% general partner ownership which is
            allocated at the Partnership level and 10 limited partner interests
            owned by Pioneer USA.

NOTE 7. OIL AND GAS INFORMATION (UNAUDITED)

        The following table presents information relating to the Partnership's
estimated proved oil and gas reserves at December 31, 2000, 1999 and 1998 and
changes in such quantities during the years then ended. All of the Partnership's
reserves are proved developed and located within the United States. The
Partnership's reserves are based on an evaluation prepared by Williamson
Petroleum Consultants, Inc., an independent petroleum consultant, using criteria
established by the Securities and Exchange Commission.




                                                     Oil and NGLs            Gas
                                                        (bbls)              (mcf)
                                                      ----------          ----------

                                                                     
Net proved reserves at January 1, 1998                   803,868             767,367
Revisions                                               (224,362)            (91,817)
Production                                               (66,527)            (68,244)
                                                      ----------          ----------

Net proved reserves at December 31, 1998                 512,979             607,306
Revisions                                                550,155             821,693
Production                                               (65,056)            (74,025)
                                                      ----------          ----------

Net proved reserves at December 31, 1999                 998,078           1,354,974
Revisions                                                113,248             (43,847)
Production                                               (69,550)            (85,556)
                                                      ----------          ----------

Net proved reserves at December 31, 2000               1,041,776           1,225,571
                                                      ==========          ==========









                                       17
   1738





        As of December 31, 2000, the estimated present value of future net
revenues of proved reserves, calculated using December 31, 2000 prices of $26.64
per barrel of oil, $13.59 per barrel of NGLs and $7.73 per mcf of gas,
discounted at 10% was approximately $8,364,000 and undiscounted was $17,283,000.

        Numerous uncertainties exist in estimating quantities of proved reserves
and future net revenues therefrom. The estimates of proved reserves and related
future net revenues set forth in this Report are based on various assumptions,
which may ultimately prove to be inaccurate. Therefore, such estimates should
not be construed as estimates of the current market value of the Partnership's
proved reserves. The Partnership emphasizes that reserve estimates are
inherently imprecise and, accordingly, the estimates are expected to change as
future information becomes available.

Disclosures about Oil & Gas Producing Activities

Standardized Measure of Discounted Future Net Cash Flows

       The standardized measure of discounted future net cash flows is computed
by applying year-end prices of oil and gas (with consideration of price changes
only to the extent provided by contractual arrangements) to the estimated future
production of proved oil and gas reserves less estimated future expenditures
(based on year-end costs) to be incurred in developing and producing the proved
reserves, discounted using a rate of 10% per year to reflect the estimated
timing of the future cash flows. A Federal income tax provision has not been
calculated as the income of the Partnership is included in the individual
Federal income tax returns of the respective partners.

       Discounted future cash flow estimates like those shown below are not
intended to represent estimates of the fair value of oil and gas properties.
Estimates of fair value should also consider anticipated future oil and gas
prices, interest rates, changes in development and production costs and risks
associated with future production. Because of these and other considerations,
any estimate of fair value is necessarily subjective and imprecise.






                                                                             For the years ended December 31,
                                                                   -------------------------------------------------------
                                                                         2000                1999               1998
                                                                   ----------------    ----------------   ----------------
                                                                                        (in thousands)
                                                                                                 
Oil and gas producing activities:
   Future cash inflows                                             $        33,121     $       24,943     $         5,585
   Future production costs                                                 (15,838)           (13,003)             (4,101)
                                                                     -------------       ------------       -------------

                                                                            17,283             11,940               1,484
   10% annual discount factor                                               (8,919)            (6,088)               (509)
                                                                     -------------       ------------       -------------

   Standardized measure of discounted future net cash flows        $         8,364     $        5,852     $           975
                                                                    ==============      =============      ==============



                                       18
   1739


                                                                             For the years ended December 31,
                                                                   -------------------------------------------------------
                                                                         2000                1999               1998
                                                                   ----------------    ----------------   ----------------
                                                                                        (in thousands)
                                                                                                 
   Oil and Gas Producing Activities:
      Oil and gas sales, net of production costs                   $        (1,470)    $         (694)    $         (409)
      Net changes in prices and production costs                             2,610              2,945             (1,842)
      Revisions of previous quantity estimates                                 721              4,406               (324)
      Accretion of discount                                                    585                 97                327
      Changes in production rates, timing and other                             66             (1,877)               (45)
                                                                     -------------       ------------       ------------

      Change in present value of future net revenues                         2,512              4,877             (2,293)
                                                                     -------------       ------------       ------------

      Balance, beginning of year                                             5,852                975              3,268
                                                                     -------------       ------------       ------------

      Balance, end of year                                         $         8,364     $        5,852     $          975
                                                                    ==============      =============      =============


NOTE 8.  MAJOR CUSTOMERS

      The following table reflects the major customers of the Partnership's oil
and gas sales (a major customer is defined as a customer whose sales exceed 10%
of total sales) during the periods ended December 31:



                                                                          2000                 1999                 1998
                                                                        --------             --------             --------

                                                                                                         
                  Mobil Oil Corporation                                       48%                  48%                 48%
                  Plains Marketing, L.P.                                      22%                  23%                -
                  Genesis Crude Oil, L.P.                                    -                    -                    26%
                  Western Gas Resources, Inc.                                  4%                   6%                 22%


        At December 31, 2000, the amounts receivable from Mobil Oil Corporation
and Plains Marketing, L.P. were $64,224 and $32,862, respectively, which are
included in the caption "Accounts receivable - oil and gas sales" in the
accompanying Balance Sheet.

        Pioneer USA is of the opinion that the loss of any one purchaser would
not have an adverse effect on the ability of the Partnership to sell its oil,
NGLs and gas production.

NOTE 9. PARTNERSHIP AGREEMENT

        The following is a brief summary of the more significant provisions of
the limited partnership agreement:


        Managing general partner - The managing general partner of the
        Partnership is Pioneer USA. Pioneer USA has the power and authority to
        manage, control and administer all Partnership affairs. As managing
        general partner and operator of the Partnership's properties, all
        production expenses are incurred by Pioneer USA and billed to the
        Partnership. The majority of the Partnership's oil and gas revenues are
        received directly by the Partnership, however, a




                                       19
   1740

        portion of the oil and gas revenue is initially received by Pioneer USA
        prior to being paid to the Partnership. Under the limited partnership
        agreement, the managing general partner pays 1% of the Partnership's
        acquisition, drilling and completion costs, and 1% of its operating and
        general and administrative expenses. In return it is allocated 1% of the
        Partnership's revenues.

        Limited partner liability - The maximum amount of liability of any
        limited partner is the total contributions of such partner plus his
        share of any undistributed profits.

        Initial capital contributions - The limited partners entered into
        subscription agreements for aggregate capital contributions of
        $11,249,000. The managing general partner is required to contribute
        amounts equal to 1% of initial Partnership capital less sales commission
        costs allocated to the limited partners and to contribute amounts
        necessary to pay costs and expenses allocated to it under the
        Partnership agreement to the extent its share of revenues does not cover
        such costs.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING
          AND FINANCIAL DISCLOSURE

None.




                                       20
   1741


                                    PART III


ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE PARTNERSHIP

The Partnership does not have any officers or directors. Under the limited
partnership agreement, the Partnership's managing general partner, Pioneer USA,
is granted the exclusive right and full authority to manage, control and
administer the Partnership's business.

Set forth below are the names, ages and positions of the directors and executive
officers of Pioneer USA. Directors of Pioneer USA are elected to serve until the
next annual meeting of stockholders or until their successors are elected and
qualified.



                                                      Age at
                                                    December 31,
         Name                                          2000                                     Position
         ----                                          ----                                     --------

                                                                          
Scott D. Sheffield                                       48                     President

Timothy L. Dove                                          44                     Executive Vice President, Chief
                                                                                  Financial Officer and Director

Dennis E. Fagerstone                                     51                     Executive Vice President and Director

Mark L. Withrow                                          53                     Executive Vice President, General
                                                                                  Counsel and Director

Danny Kellum                                             46                     Executive Vice President - Domestic
                                                                                  Operations and Director

Rich Dealy                                               34                     Vice President and Chief Accounting
                                                                                  Officer


        Scott D. Sheffield. Mr. Sheffield is a graduate of The University of
Texas with a B.S. in Petroleum Engineering. Since August 1997, he has served as
President, Chief Executive Officer and a director of Pioneer and President of
Pioneer USA. Mr. Sheffield assumed the position of Chairman of the Board of
Pioneer in August 1999. He served as a director of Pioneer USA from August 1997
until his resignation from the board in June 1999. Mr. Sheffield was the
President and a director of Parker & Parsley Petroleum Company ("Parker &
Parsley") from May 1990 until August 1997 and was the Chairman of the Board and
Chief Executive Officer of Parker & Parsley from October 1990 until August 1997.
He was the sole director of Parker & Parsley from May 1990 until October 1990.
Mr. Sheffield joined Parker & Parsley Development Company ("PPDC"), a
predecessor of Parker & Parsley, as a petroleum engineer in 1979. He served as
Vice President - Engineering of PPDC from September 1981 until April 1985 when
he was elected President and a director. In March 1989, Mr. Sheffield was
elected Chairman of the Board and Chief Executive Officer of PPDC. Before
joining PPDC's predecessor, Mr. Sheffield was employed as a production and
reservoir engineer for Amoco Production Company.



                                       21
   1742


        Timothy L. Dove. Mr. Dove earned a B.S. in Mechanical Engineering from
Massachusetts Institute of Technology in 1979 and received his M.B.A. in 1981
from the University of Chicago. He became Executive Vice President - Business
Development of Pioneer and Pioneer USA in August 1997 and was also appointed a
director of Pioneer USA in August 1997. Mr. Dove assumed the position of Chief
Financial Officer of Pioneer and Pioneer USA effective February 1, 2000. Mr.
Dove joined Parker & Parsley in May 1994 as Vice President - International and
was promoted to Senior Vice President - Business Development in October 1996, in
which position he served until August 1997. Prior to joining Parker & Parsley,
Mr. Dove was employed with Diamond Shamrock Corp., and its successor, Maxus
Energy Corp, in various capacities in international exploration and production,
marketing, refining and marketing and planning and development.

        Dennis E. Fagerstone. Mr. Fagerstone, a graduate of the Colorado School
of Mines with a B.S. in Petroleum Engineering, became an Executive Vice
President of Pioneer and Pioneer USA in August 1997. He was also appointed a
director of Pioneer USA in August 1997. He served as Executive Vice President
and Chief Operating Officer of MESA Inc. ("Mesa") from March 1, 1997 until
August 1997. From October 1996 to February 1997, Mr. Fagerstone served as Senior
Vice President and Chief Operating Officer of Mesa and from May 1991 to October
1996, he served as Vice President - Exploration and Production of Mesa. From
June 1988 to May 1991, Mr. Fagerstone served as Vice President - Operations of
Mesa.

        Mark L. Withrow. Mr. Withrow, a graduate of Abilene Christian University
with a B. S. in Accounting and Texas Tech University with a Juris Doctorate
degree, became Executive Vice President, General Counsel and Secretary of
Pioneer and Pioneer USA in August 1997. He was also appointed a director of
Pioneer USA in August 1997. Mr. Withrow was Vice President - General Counsel of
Parker & Parsley from January 1991, when he joined Parker & Parsley, to January
1995, when he was appointed Senior Vice President - General Counsel. He was
Parker & Parsley's Secretary from August 1992 until August 1997. Prior to
joining Parker & Parsley, Mr. Withrow was the managing partner of the law firm
of Turpin, Smith, Dyer, Saxe & MacDonald, Midland, Texas.

        Danny Kellum. Mr. Kellum, who received a Bachelor of Science degree in
Petroleum Engineering from Texas Tech University in 1979, was elected Executive
Vice President - Domestic Operations of Pioneer and Pioneer USA on May 18, 2000
and Director of Pioneer USA on February 1, 2000. From January 2000 until May
2000, Mr. Kellum served as Vice President - Domestic Operations of Pioneer and
Pioneer USA. Mr. Kellum served as Vice President Permian Division of Pioneer and
Pioneer USA from April 1998 until December 1999. From 1989 until 1994 he served
as Spraberry District Manager and as Vice President of the Spraberry and Permian
Division for Parker & Parsley until August of 1997. Mr. Kellum joined Parker &
Parsley as an operations engineer in 1981 after a brief career with Mobil Oil
Corporation.

        Rich Dealy. Mr. Dealy is a graduate of Eastern New Mexico University
with a B.B.A. in Accounting and Finance and is a Certified Public Accountant. He
became Vice President and Chief Accounting Officer of Pioneer and Pioneer USA in
February 1998. Mr. Dealy served as Controller of Pioneer USA from August 1997 to
February 1998. He served as Controller of Parker & Parsley from August 1995 to
August 1997. Mr. Dealy joined Parker & Parsley as an Accounting Manager in July,
1992. He was previously employed with KPMG Peat Marwick as an Audit Senior, in
charge of Parker & Parsley's audit.




                                       22
   1743


ITEM 11.   EXECUTIVE COMPENSATION

The Partnership does not have any directors or officers. Management of the
Partnership is performed by the managing general partner. The Partnership
participates in oil and gas activities through an income tax partnership (the
"Program") pursuant to the Program agreement. Under the Program agreement,
Pioneer USA pays approximately 25% of the Program's acquisition, drilling and
completion costs and approximately 35% of its operating and general and
administrative expenses. In return, they are allocated approximately 35% of the
Program's revenues.

The Partnership does not directly pay any salaries of the executive officers or
employees of Pioneer USA, but does pay a portion of Pioneer USA's general and
administrative expenses of which these salaries are a part.

See Notes 6 and 9 of Notes to Financial Statements included in "Item 8.
Financial Statements and Supplementary Data" for information regarding fees and
reimbursements paid to the managing general partner by the Partnership.

ITEM 12.   SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

(a)        Beneficial owners of more than five percent

The Partnership is not aware of any person who beneficially owns 5% or more of
the outstanding limited partnership interests of the Partnership. Pioneer USA
owned 10 limited partner interests at January 1, 2001.

(b)        Security ownership of management

The Partnership does not have any officers or directors. The managing general
partner of the Partnership, Pioneer USA, has the exclusive right and full
authority to manage, control and administer the Partnership's business. Under
the limited partnership agreement, limited partners holding a majority of the
outstanding limited partnership interests have the right to take certain
actions, including the removal of the managing general partner or any other
general partner. The Partnership is not aware of any current arrangement or
activity which may lead to such removal. The Partnership is not aware of any
officer or director of Pioneer USA who beneficially owns limited partnership
interests in the Partnership.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

Transactions with the managing general partner

Pursuant to the limited partnership agreement, the Partnership had the following
related party transactions with the managing general partner during the years
ended December 31:








                                       23
   1744




                                                                             2000                 1999                 1998
                                                                        -------------        -------------        -------------
                                                                                                         
      Payment of lease operating and supervision
         charges in accordance with standard industry
         operating agreements                                           $     196,507        $    189,784         $    182,097

      Reimbursement of general and administrative
         expenses                                                       $      38,999        $     33,982         $     27,503


Under the limited partnership agreement, the managing general partner pays 1% of
the Partnership's acquisition, drilling and completion costs and 1% of its
operating and general and administrative expenses. In return, it is allocated 1%
of the Partnership's revenues. Also, see Notes 6 and 9 of Notes to Financial
Statements included in "Item 8. Financial Statements and Supplementary Data",
regarding the Partnership's participation with the managing general partner in
oil and gas activities of the Program.




                                       24
   1745


                                     PART IV

ITEM 14.  EXHIBITS, FINANCIAL STATEMENT SCHEDULES AND REPORTS ON FORM 8-K

(a)     1.      Financial statements

                The following are filed as part of this Report:

                 Independent Auditors' Report

                 Balance sheets as of December 31, 2000 and 1999

                 Statements of operations for the years ended December 31, 2000,
                   1999 and 1998

                 Statements of partners' capital for the years ended December
                   31, 2000, 1999 and 1998

                 Statements of cash flows for the years ended December 31, 2000,
                   1999 and 1998

                 Notes to financial statements

        2.      Financial statement schedules

                All financial statement schedules have been omitted since the
                required information is in the financial statements or notes
                thereto, or is not applicable nor required.

(b)     Reports on Form 8-K

None.

(c)     Exhibits

        The exhibits listed on the accompanying index to exhibits are filed or
        incorporated by reference as part of this Report.



                                       25
   1746


                               S I G N A T U R E S


        Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this Report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                     PARKER & PARSLEY 91-B, L.P.

Dated: March 27, 2001          By:   Pioneer Natural Resources USA, Inc.
                                       Managing General Partner


                                     By:      /s/ Scott D. Sheffield
                                              --------------------------------
                                              Scott D. Sheffield, President

        Pursuant to the requirements of the Securities Exchange Act of 1934,
this Report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the date indicated.



                                                                                                        
/s/ Scott D. Sheffield                              President of Pioneer USA                                   March 27, 2001
--------------------------------------------
Scott D. Sheffield


/s/ Timothy L. Dove                                 Executive Vice President, Chief                            March 27, 2001
--------------------------------------------        Financial Officer and Director of
Timothy L. Dove                                     Pioneer USA


/s/ Dennis E. Fagerstone                            Executive Vice President and                               March 27, 2001
--------------------------------------------        Director of Pioneer USA
Dennis E. Fagerstone


/s/ Mark L. Withrow                                 Executive Vice President, General                          March 27, 2001
--------------------------------------------        Counsel and Director of Pioneer USA
Mark L. Withrow


/s/ Danny Kellum                                    Executive Vice President - Domestic                        March 27, 2001
--------------------------------------------        Operations and Director of Pioneer
Danny Kellum                                        USA


/s/ Rich Dealy                                      Vice President and Chief Accounting                        March 27, 2001
--------------------------------------------        Officer of Pioneer USA
Rich Dealy




                                       26
   1747


                           PARKER & PARSLEY 91-B, L.P.

                                INDEX TO EXHIBITS


        The following documents are incorporated by reference in response to
Item 14(c):



         Exhibit No.                              Description                                                            Page
         -----------                              -----------                                                            ----

                                                                                                                  
           3(a)                      Form of Agreement of Limited Partnership                                             -
                                     of Parker & Parsley 91-B, L.P. incorporated
                                     by reference to Exhibit A of the Partnership's
                                     Registration Statement on Form S-1
                                     (Registration No. 33-38582) (hereinafter
                                     called the Partnership's Registration Statement)

           4(b)                      Form of Limited Partner Subscription Agreement                                       -
                                     incorporated by reference to Exhibit C of the
                                     Partnership's Registration Statement

           4(b)                      Form of General Partner Subscription Agreement                                       -
                                     incorporated by reference to Exhibit D of the
                                     Partnership's Registration Statement

           4(b)                      Power of Attorney incorporated by reference to                                       -
                                     Exhibit B of the Partnership's Registration
                                     Statement

           4(c)                      Specimen Certificate of Limited Partnership                                          -
                                     Interest incorporated by reference to Exhibit 4.3
                                     of Amendment No. 2 of the Partnership's
                                     Registration Statement

          10(b)                      Development Drilling Program Agreement                                               -
                                     incorporated by reference to Exhibit B of the
                                     Partnership's Registration Statement





                                       27
   1748





                           PARKER & PARSLEY 91-B, L.P.

SELECTED FINANCIAL DATA

The following selected financial data for the Partnership should be read in
connection with Management's Discussion and Analysis of Financial Condition and
Results of Operations and the financial statements included in the attached
supplemental information.



                                        Three months
                                            ended
                                          March 31,                       Years ended December 31,
                                   ---------------------   --------------------------------------------------------------
                                     2001        2000         2000         1999         1998         1997         1996
                                   --------   ----------   ----------   ----------   ----------   ----------   ----------
                                                                                          
Operating results:
  Oil and gas sales                $          $  453,588   $2,046,224   $1,136,073   $  873,012   $1,273,373   $1,632,595
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Impairment of oil and
    gas properties                 $          $       --   $       --   $       --   $  295,542   $  323,078   $       --
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Net income (loss)                $          $  277,672   $1,354,094   $  490,669   $ (177,905)  $  222,730   $  924,002
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Allocation of net income
    (loss):
       Managing general
         partner                   $          $    2,777   $   13,541   $    4,907   $   (1,779)  $    2,227   $    9,240
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

       Limited partners            $          $  274,895   $1,340,553   $  485,762   $ (176,126)  $  220,503   $  914,762
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' net
    income (loss) per limited
    partnership interest           $          $    24.44   $   119.17   $    43.18   $   (15.66)  $    19.60   $    81.32
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

  Limited partners' cash
    distributions per limited
    partnership interest           $          $    21.87   $   117.75   $    42.78   $    36.76   $    75.32   $    84.40
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========

At year end:
  Identifiable assets              $          $1,863,707   $1,829,460   $1,843,803   $1,820,336   $2,424,808   $3,051,464
                                   ========   ==========   ==========   ==========   ==========   ==========   ==========




   1749
                                     PART II

                     INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 20.  INDEMNIFICATION OF OFFICERS AND DIRECTORS.


     Article Twelfth of the Amended and Restated Certificate of Incorporation of
Pioneer Parent provides that Pioneer Parent must indemnify its officers and
directors to the extent allowed by the Delaware General Corporation Law.
Pursuant to Section 145 of the Delaware General Corporation Law, Pioneer Parent
generally has the power to indemnify its present and former directors and
officers against expenses and liabilities incurred by them in connection with
any suit to which they are, or are threatened to be made, a party by reason of
their serving in those positions so long as they acted in good faith and in a
manner they reasonably believed to be in, or not opposed to, the best interests
of Pioneer Parent, and with respect to any criminal action, they had no
reasonable cause to believe their conduct was unlawful. With respect to suits by
or in the right of Pioneer Parent, however, indemnification is generally limited
to attorneys' fees and other expenses and is not available if the person is
adjudged to be liable to Pioneer Parent unless the court determines that
indemnification is appropriate. The statute expressly provides that the power to
indemnify authorized thereby is not exclusive of any rights granted under any
by-law, agreement, vote of stockholders or disinterested directors, or
otherwise. Pioneer Parent also has the power to purchase and maintain insurance
for its directors and officers. Additionally, Article Twelfth of the Amended and
Restated Certificate of Incorporation of Pioneer Parent provides that, in the
event that an officer or director files suit against Pioneer Parent seeking
indemnification of liabilities or expenses incurred, the burden will be on
Pioneer Parent to prove that the indemnification would not be permitted under
the Delaware General Corporation Law.

     Pioneer Parent has entered into indemnification agreements with each of its
directors and officers. These agreements provide that Pioneer Parent must,
within 30 days of a request, indemnify an officer or director for liabilities
incurred to the fullest extent permitted by the Delaware General Corporation
Law. Pioneer Parent must, within two days of a request, indemnify an officer or
director for expenses incurred in the defense of a claim or other proceeding.
The obligation of Pioneer Parent to provide the indemnification does not apply
if, before the date on which Pioneer Parent must provide the indemnification,
Pioneer Parent's board of directors, or a representative chosen by the board of
directors, concludes that indemnification would be improper under the Delaware
General Corporation Law.

     The preceding discussion of Pioneer Parent's Amended and Restated
Certificate of Incorporation, Section 145 of the Delaware General Corporation
Law, and the indemnification agreements is not intended to be exhaustive and is
qualified in its entirety by such Amended and Restated Certificate of
Incorporation, Section 145 of the Delaware General Corporation Law, and such
indemnification agreements.





                                      II-1
   1750
ITEM 21.  EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

     The following exhibits are filed with the registration statement:




   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         2.1        Agreement and Plan of Merger dated as of       , 2001, among
                    Pioneer Parent, Pioneer USA and the partnerships named
                    therein (included as Appendix F to the proxy
                    statement/prospectus forming a part of this Registration
                    Statement).

         3.1        Amended and Restated Certificate of Incorporation of Pioneer
                    Parent (incorporated by reference to Exhibit 3.1 to Pioneer
                    Parent's Registration Statement on Form S-4 dated June 27,
                    1997, Registration No. 333-26951).

         3.2        Restated Bylaws of Pioneer Parent (incorporated by reference
                    to Exhibit 3.2 to Pioneer Parent's Registration Statement on
                    Form S-4 dated June 27, 1997, Registration No. 333-26951).

         3.3        Certificate of Designations of Special Preferred Voting
                    Stock (incorporated by reference to Exhibit 3.3 of Pioneer
                    Parent's Registration Statement on Form S-3, Registration
                    No. 333-42315, filed with the SEC on December 17, 1997).

         3.4        Terms and Conditions of Exchangeable Shares (incorporated by
                    reference to Annex F to the Definitive Joint Management
                    Information Circular and Proxy Statement of Pioneer Parent
                    and Chauvco, File No. 001-13245, filed with the SEC on
                    November 17, 1997).

         4.1        Form of Certificate of Common Stock, par value $.01 per
                    share, of Pioneer Parent (incorporated by reference to
                    Exhibit 4.1 to Pioneer Parent's Registration Statement on
                    Form S-4 dated June 27, 1997, Registration No. 333-26951).

         4.2        Form of Certificate of Special Preferred Voting Stock
                    (incorporated by reference to Exhibit 4.1 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         4.3        Form of Certificate of Exchangeable Shares (incorporated by
                    reference to Exhibit 4.2 to Pioneer Parent's Current Report
                    on Form 8-K, File No. 001-13245, filed with the SEC on
                    January 2, 1998).

         5.1*       Form of opinion of Vinson & Elkins L.L.P. as to the legality
                    of the securities to be registered.

         8.1*       Form of opinion of Vinson & Elkins L.L.P., regarding tax
                    matters.

         8.2        Form of opinion of      , as special legal counsel to the
                    limited partners, regarding tax matters as required by the
                    partnership agreement of each partnership (included as
                    Exhibit A to Appendix E to the proxy statement/prospectus
                    forming a part of this Registration Statement).

         9.1        Voting and Exchange Trust Agreement dated as of December 18,
                    1997, among Pioneer Parent, Pioneer Natural Resources
                    (Canada) Ltd. and Montreal Trust Company of Canada, as
                    trustee (incorporated by reference to Exhibit 2.4 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         10.1       Indenture dated July 2, 1996, among Pioneer USA (formerly
                    Mesa Operating Co. ("MOC")), as issuer, Pioneer Parent, as
                    guarantor, and Harris Trust and Savings Bank, as trustee,
                    relating to the 11-5/8% Senior Subordinated Discount Notes
                    Due 2006 (incorporated by reference to Exhibit 4.17 to MESA
                    Inc.'s Quarterly Report on Form 10-Q for the period ended
                    June 30, 1996).






                                      II-2
   1751



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.2       First Supplemental Indenture dated as of April 15, 1997,
                    among Pioneer USA (formerly MOC), as issuer, MESA Inc.
                    ("Mesa"), the subsidiary guarantors named therein, Pioneer
                    Parent and Harris Trust and Savings Bank, as trustee, with
                    respect to the indenture identified above as Exhibit 10.1
                    (incorporated by reference to Exhibit 10.1 to Pioneer
                    Parent's Quarterly Report on Form 10-Q for the period ended
                    September 30, 1997, File No. 001-13245).

         10.3       Second Supplemental Indenture dated as of August 7, 1997,
                    among Pioneer USA (formerly MOC), as issuer, Mesa, the
                    subsidiary guarantors named therein, Pioneer Parent and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.1 (incorporated
                    by reference to Exhibit 10.2 to Pioneer Parent's Quarterly
                    Report on Form 10-Q for the period ended September 30, 1997,
                    File No. 001-13245).

         10.4       Third Supplemental Indenture dated as of December 18, 1997,
                    among Pioneer USA, the subsidiary guarantors named therein,
                    Pioneer Parent and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.1 (incorporated by reference to Exhibit 10.12 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.5       Fourth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer USA (formerly MOC), Pioneer Parent, Pioneer
                    NewSub1, Inc. and Harris Trust and Savings Bank, as trustee,
                    with respect to the indenture identified above as Exhibit
                    10.1 (incorporated by reference to Exhibit 10.13 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         10.6       Fifth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer NewSub1, Inc. (as successor to Pioneer USA),
                    Pioneer Parent, Pioneer DebtCo., Inc. and Harris Trust and
                    Savings Bank, as trustee, with respect to the indenture
                    identified above as Exhibit 10.1 (incorporated by reference
                    to Exhibit 10.14 to Pioneer Parent's Current Report on Form
                    8-K, File No. 001-13245, filed with the SEC on January 2,
                    1998).

         10.7       Sixth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer DebtCo. Inc. (as successor to Pioneer NewSub1,
                    Inc.), Pioneer Parent, and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.1 (incorporated by reference to Exhibit 10.15 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.8       Indenture dated July 2, 1996, among Pioneer USA (formerly
                    MOC), as issuer, Pioneer Parent (as Mesa's successor), as
                    guarantor, and Harris Trust and Savings Bank, as trustee,
                    relating to the 10-5/8% Senior Subordinated Notes Due 2006
                    (incorporated by reference to Exhibit 4.18 to Mesa's
                    Quarterly Report on Form 10-Q for the period ended June 30,
                    1996).

         10.9       First Supplemental Indenture dated as of April 15, 1997,
                    among Pioneer USA (formerly MOC), as issuer, Mesa, the
                    subsidiary guarantors named therein, Pioneer Parent and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.8 (incorporated
                    by reference to Exhibit 10.3 to Pioneer Parent's Quarterly
                    Report on Form 10-Q for the period ended September 30, 1997,
                    File No. 001-13245).

         10.10      Second Supplemental Indenture dated as of August 7, 1997,
                    among Pioneer USA (formerly MOC), as issuer, Mesa, the
                    subsidiary guarantors named therein, Pioneer Parent and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.8 (incorporated
                    by reference to Exhibit 10.4 to Pioneer Parent's Quarterly
                    Report on Form 10-Q for the period ended September 30, 1997,
                    File No. 001-13245).





                                      II-3
   1752



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.11      Third Supplemental Indenture dated as of December 18, 1997,
                    among Pioneer USA, the subsidiary guarantors named therein,
                    Pioneer Parent and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.8 (incorporated by reference to Exhibit 10.6 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.12      Fourth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer USA, Pioneer Parent, Pioneer NewSub1, Inc. and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.8 (incorporated
                    by reference to Exhibit 10.7 to Pioneer Parent's Current
                    Report on Form 8-K, File No. 001-13245, filed with the SEC
                    on January 2, 1998).

         10.13      Fifth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer NewSub1, Inc. (as successor to Pioneer USA),
                    Pioneer Parent, Pioneer DebtCo, Inc. and Harris Trust and
                    Savings Bank, as trustee, with respect to the indenture
                    identified above as Exhibit 10.8 (incorporated by reference
                    to Exhibit 10.8 to Pioneer Parent's Current Report on Form
                    8-K, File No. 001-13245, filed with the SEC on January 2,
                    1998).

         10.14      Sixth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer DebtCo, Inc. (as successor to Pioneer NewSub1,
                    Inc.), Pioneer Parent and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.8 (incorporated by reference to Exhibit 10.9 to
                    Pioneer Parent's Current Report on Form 8-K, File No. 001-
                    13245, filed with the SEC on January 2, 1998).

         10.15      Indenture dated April 12, 1995, between Pioneer USA
                    (successor to Parker & Parsley Petroleum Company ("Parker &
                    Parsley")) and The Chase Manhattan Bank (National
                    Association), as trustee (incorporated by reference to
                    Exhibit 4.1 to Parker & Parsley's Current Report on Form 8-K
                    dated April 12, 1995, File No. 1-10695).

         10.16      First Supplemental Indenture dated as of August 7, 1997,
                    among Parker & Parsley, The Chase Manhattan Bank, as
                    trustee, and Pioneer USA, with respect to the indenture
                    identified above as Exhibit 10.15 (incorporated by reference
                    to Exhibit 10.5 to Pioneer Parent's Quarterly Report on Form
                    10-Q for the period ended September 30, 1997, File No.
                    001-13245).

         10.17      Second Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer USA, Pioneer NewSub1, Inc. and The Chase
                    Manhattan Bank, as trustee, with respect to the indenture
                    identified above as Exhibit 10.15 (incorporated by reference
                    to Exhibit 10.17 to Pioneer Parent's Current Report on Form
                    8-K, File No. 001-13245, filed with the SEC on January 2,
                    1998).

         10.18      Third Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer NewSub1, Inc. (as successor to Pioneer USA),
                    Pioneer DebtCo, Inc. and The Chase Manhattan Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.15 (incorporated by reference to Exhibit 10.18 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.19      Fourth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer DebtCo, Inc. (as successor to Pioneer NewSub1,
                    Inc., as successor to Pioneer USA), Pioneer Parent, Pioneer
                    USA and The Chase Manhattan Bank, as trustee, with respect
                    to the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 10.19 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001- 13245,
                    filed with the SEC on January 2, 1998).





                                      II-4
   1753




   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.20      Guarantee dated as of December 30, 1997, by Pioneer USA
                    relating to $150,000,000 in aggregate principal amount of
                    8-7/8% Senior Notes due 2005 and $150,000,000 in aggregate
                    principal amount of 8 1/4% Senior Notes due 2007 issued
                    under the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 10.20 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         10.21      Form of 8-7/8% Senior Notes Due 2005 dated as of April 12,
                    1995, in the aggregate principal amount of $150,000,000,
                    together with Officers' Certificate dated April 12, 1995,
                    establishing the terms of the 8-7/8% Senior Notes Due 2005
                    pursuant to the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 4.2 to Parker &
                    Parsley's Quarterly Report on Form 10-Q for the period ended
                    June 30, 1995, File No. 001-10695).

         10.22      Form of 8 1/4% Senior Notes due 2007 dated as of August 22,
                    1995, in the aggregate principal amount of $150,000,000,
                    together with Officers' Certificate dated August 22, 1995,
                    establishing the terms of the 8 1/4% Senior Notes due 2007
                    pursuant to the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 1.2 to Parker &
                    Parsley's Current Report on Form 8-K dated August 17, 1995,
                    File No. 001-10695).

         10.23      Indenture dated January 13, 1998, between Pioneer Parent and
                    The Bank of New York, as trustee (incorporated by reference
                    to Exhibit 99.1 to Pioneer Parent's and Pioneer USA's
                    Current Report on Form 8-K, File No. 001-13245, filed with
                    the SEC on January 14, 1998).

         10.24      First Supplemental Indenture dated as of January 13, 1998,
                    among Pioneer Parent, Pioneer USA, as the subsidiary
                    guarantor, and The Bank of New York, as trustee, with
                    respect to the indenture identified above as Exhibit 10.23
                    (incorporated by reference to Exhibit 99.2 to Pioneer
                    Parent's and Pioneer USA's Current Report on Form 8-K, File
                    No. 001-13245, filed with the SEC on January 14, 1998).

         10.25      Form of 6.50% Senior Notes Due 2008 of Pioneer Parent
                    (incorporated by reference to Exhibit 99.3 to Pioneer
                    Parent's and Pioneer USA's Current Report on Form 8-K, File
                    No. 001-13245, filed with the SEC on January 14, 1998).

         10.26      Form of 7.20% Senior Notes Due 2028 of Pioneer Parent
                    (incorporated by reference to Exhibit 99.4 to Pioneer
                    Parent's and Pioneer USA's Current Report on Form 8-K, File
                    No. 001-13245, filed with the SEC on January 14, 1998).

         10.27      Guarantee (2008 Notes) dated as of January 13, 1998, entered
                    into by Pioneer USA (incorporated by reference to Exhibit
                    99.5 to Pioneer Parent's and Pioneer USA's Current Report on
                    Form 8-K, File No. 001-13245, filed with the SEC on January
                    14, 1998).

         10.28      Guarantee (2028 Notes) dated as of January 13, 1998, entered
                    into by Pioneer USA (incorporated by reference to Exhibit
                    99.6 to Pioneer Parent's and Pioneer USA's Current Report on
                    Form 8-K, File No. 001-13245, filed with the SEC on January
                    14, 1998).

         10.29      1991 Stock Option Plan of Mesa (incorporated by reference to
                    Exhibit 10(v) to Mesa's Annual Report on Form 10-K for the
                    period ended December 31, 1991).

         10.30      1996 Incentive Plan of Mesa (incorporated by reference to
                    Exhibit 10.28 to Pioneer Parent's Registration Statement on
                    Form S-4 dated June 27, 1997, Registration No. 333-26951).

         10.31      Parker & Parsley Long-Term Incentive Plan dated February 19,
                    1991 (incorporated by reference to Exhibit 4.1 to Parker &
                    Parsley's Registration Statement on Form S-8, Registration
                    No. 33-38971).





                                      II-5
   1754





   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.32      First Amendment to the Parker & Parsley Long-Term Incentive
                    Plan dated August 23, 1991 (incorporated by reference to
                    Exhibit 10.2 to Parker & Parsley's Registration Statement on
                    Form S-1 dated February 28, 1992, Registration No.
                    33-46082).

         10.33      Pioneer Parent's Long-Term Incentive Plan (incorporated by
                    reference to Exhibit 4.1 to Pioneer Parent's Registration
                    Statement on Form S-8, Registration No. 333-35087).

         10.34      First Amendment to Pioneer Parent's Long-Term Incentive
                    Plan, effective as of November 23, 1998 (incorporated by
                    reference to Exhibit 10.72 to Pioneer Parent's Annual Report
                    on Form 10-K for the period ended December 31, 1999, File
                    No. 001-13245.

         10.35      Amendment No. 2 to Pioneer Parent's Long-Term Incentive
                    Plan, effective as of May 20, 1998 (incorporated by
                    reference to Exhibit 10.73 to Pioneer Parent's Annual Report
                    on Form 10-K for the period ended December 31, 1999, File
                    No. 001-13245).

         10.36      Amendment No. 3 to Pioneer Parent's Long-Term Incentive
                    Plan, effective as of February 17, 2000 (incorporated by
                    reference to Exhibit 10.76 to Pioneer Parent's Annual Report
                    on Form 10-K for the period ended December 31, 1999, File
                    No. 001-13245).

         10.37      Pioneer Parent's Employee Stock Purchase Plan (incorporated
                    by reference to Exhibit 4.1 to Pioneer Parent's Registration
                    Statement on Form S-8, Registration No. 333-35165).

         10.38      Amendment No. 1 to Pioneer Parent's Employee Stock Purchase
                    Plan dated December 9, 1998 (incorporated by reference to
                    Pioneer Parent's Annual Report on Form 10-K for the year
                    ended December 31, 1998, File No. 001-13245).

         10.39      Amendment No. 2 to Pioneer Parent's Employee Stock Purchase
                    Plan dated December 14, 1999 (incorporated by reference to
                    Exhibit 10.74 to Pioneer Parent's Annual Report on Form 10-K
                    for the period ended December 31, 1999, File No. 001-13245).

         10.40      Pioneer Parent's Deferred Compensation Retirement Plan
                    (incorporated by reference to Exhibit 4.1 to Pioneer
                    Parent's Registration Statement on Form S-8, Registration
                    No. 333- 39153).

         10.41      Pioneer USA 401(k) Plan (incorporated by reference to
                    Exhibit 4.1 to Pioneer Parent's Registration Statement on
                    Form S-8, Registration No. 333-39249).

         10.42      Pioneer USA Matching Plan (incorporated by reference to
                    Exhibit 10.42 to Pioneer Parent's Annual Report on Form 10-K
                    for the year ended December 31, 1997, File No. 001-13245).

         10.43      Omnibus Amendment to Nonstatutory Stock Option Agreements,
                    included as part of the Parker & Parsley Long-Term Incentive
                    Plan dated as of November 16, 1995, between Parker & Parsley
                    and named executive officers identified on Schedule 1
                    thereto, setting forth additional details relating to the
                    Parker & Parsley Long-Term Incentive Plan (incorporated by
                    reference to Parker & Parsley's Annual Report on Form 10-K
                    for the period ended December 31, 1995, File No. 001-10695).

         10.44      Severance Agreement dated as of August 8, 1997, between
                    Pioneer Parent and Scott D. Sheffield, together with a
                    schedule identifying substantially identical agreements
                    between Pioneer Parent and each of the other named executive
                    officers identified on Schedule I, for the purpose of
                    defining the payment of certain benefits upon the
                    termination of the officer's employment under certain
                    circumstances (incorporated by reference to Exhibit 10.7 to
                    Pioneer Parent's Quarterly Report on Form 10-Q for the
                    period ended September 30, 1997, File No. 001-13245).





                                      II-6
   1755



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.45      Indemnification Agreement dated as of August 8, 1997,
                    between Pioneer Parent and Scott D. Sheffield, together with
                    a schedule identifying substantially identical agreements
                    between Pioneer Parent and each of Pioneer Parent's other
                    directors and named executive officers identified on
                    Schedule I thereto (incorporated by reference to Exhibit
                    10.8 to Pioneer Parent's Quarterly Report on Form 10-Q for
                    the period ended September 30, 1997, File No. 001-13245).

         10.46      "B" Contract Production Allocation Agreement dated July 29,
                    1991, and effective as of January 1, 1991, between Colorado
                    Interstate Gas Company and Mesa Operating Limited
                    Partnership (incorporated by reference to Exhibit 10(r) to
                    Mesa's Annual Report on Form 10-K for the period ended
                    December 31, 1991).

         10.47      Amendment to "B" Contract Production Allocation Agreement
                    effective as of January 1, 1993, between Colorado Interstate
                    Gas Company and Mesa Operating Limited Partnership
                    (incorporated by reference to Exhibit 10.24 to Mesa's
                    Registration Statement on Form S-1, Registration No.
                    33-51909).

         10.48      Voting and Shareholders Agreement dated as of February 8,
                    2000, among Prize Energy Corp. and its stockholders
                    (incorporated by reference to Exhibit 10.1 to Pioneer
                    Parent's statement on Schedule 13D relating to common stock
                    of Prize Energy Corp., filed with the SEC on February 18,
                    2000, File No. 005-54797).

         10.49      Second Supplemental Indenture dated as of April 11, 2000,
                    among Pioneer Parent, Pioneer USA, as the subsidiary
                    guarantor, and the Bank of New York, as trustee, with
                    respect to the Indenture dated January 13, 1998, between
                    Pioneer Parent and The Bank of New York, as trustee
                    (incorporated by reference to Exhibit 10.1 to Pioneer
                    Parent's Quarterly Report on Form 10-Q, filed with the SEC
                    on May 11, 2000).

         10.50      Form of 9-5/8% Senior Notes Due April 1, 2010 dated as of
                    April 11, 2000, in the aggregate principal amount of
                    $425,000,000, together with Trustee's Certificate of
                    Authentication dated April 11, 2000, establishing the terms
                    of the 9-5/8% Senior Notes Due April 1, 2010 pursuant to the
                    Second Supplemental Indenture identified above as Exhibit
                    10.49 (incorporated by reference to Exhibit 10.2 to Pioneer
                    Parent's Quarterly Report on Form 10-Q, filed with the SEC
                    on May 11, 2000).

         10.51      Guarantee, dated as of April 11, 2000, by Pioneer USA, as
                    the subsidiary guarantor, relating to the $425,000,000
                    aggregate principal amount of 9-5/8% Senior Notes Due April
                    1, 2010 issued under the Second Supplemental Indenture
                    identified above as Exhibit 10.49 (incorporated by reference
                    to Exhibit 10.3 to Pioneer Parent's Quarterly Report on Form
                    10-Q, filed with the SEC on May 11, 2000).

         10.52      $575,000,000 Credit Agreement dated as of May 31, 2000,
                    among Pioneer Parent, as the borrower, Bank of America,
                    N.A., as the administrative agent, Credit Suisse First
                    Boston, as the documentation agent, The Chase Manhattan
                    Bank, as the syndication agent, and certain lenders
                    (incorporated by reference to Exhibit 10.4 to Pioneer
                    Parent's Quarterly Report on Form 10-Q, filed with the SEC
                    on August 9, 2000).

         10.53      Agreement and Plan of Merger dated as of November 28, 2000,
                    among Pioneer Parent, Pioneer USA, Parker & Parsley
                    Employees Producing Properties 87-A, Ltd., Parker & Parsley
                    Employees Producing Properties 87-B Ltd., P&P Employees
                    Producing Properties 88-A, L.P., P&P Employees 89-A Conv.,
                    L.P., P&P Employees 89-B Conv., L.P., P&P Employees Private
                    89, L.P., P&P Employees 90-A Conv., L.P., P& P Employees
                    90-B Conv., L.P., P&P Employees 90-C Conv., L.P., P&P
                    Employees Private 90, L.P., P&P Employees 90 Spraberry
                    Private Development, L.P., P&P Employees 91-A Conv., L.P.
                    and P&P Employees 91-B Conv., L.P. (incorporated by
                    reference to Exhibit 10.53 to Pioneer Parent's Annual Report
                    on Form 10-K, filed with the SEC on February 27, 2001).





                                      II-7
   1756



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         23.1       Consent of Vinson & Elkins L.L.P. (included in the opinions
                    filed as Exhibits 5.1 and 8.1 to this Registration
                    Statement).

         23.2       Consent of ______________ (included in the opinion filed as
                    Exhibit 8.2 to this Registration Statement).

         23.3*      Consent of Ernst & Young LLP.

         23.4*      Consent of Williamson Petroleum Consultants, Inc.

         24.1#      Powers of Attorney of directors and officers of Pioneer
                    Parent.

         99.1       Form of opinion of Robert A. Stanger & Co, Inc. (included as
                    Appendix D to the proxy statement/prospectus forming a part
                    of this Registration Statement).

         99.2*      Consent of Robert A. Stanger & Co., Inc.

         99.3*      Form of Certification of Non-Foreign Status for Individual
                    Partners.

         99.4*      Form of Certification of Non-Foreign Status for Individual
                    Partners that are Entities.

         99.5*      Form of Proxy for Special Meeting of Limited Partners of
                    Each of 46 Parker & Parsley Limited Partnerships.

         99.6*      Form of Letter to Custodians and Consent.




--------------------

*  Filed herewith.
#  Previously filed.




                                      II-8
   1757
ITEM 22.  UNDERTAKINGS.


     Insofar as indemnification for liabilities arising under the Securities Act
of 1933 may be permitted to directors, officers and controlling persons of
Pioneer Parent pursuant to the foregoing provisions, or otherwise, Pioneer
Parent has been advised that in the opinion of the Securities and Exchange
Commission such indemnification is against public policy as expressed in the
Securities Act of 1933 and is, therefore, unenforceable. In the event that a
claim for indemnification against such liabilities, other than the payment by
Pioneer Parent of expenses incurred or paid by a director, officer or
controlling person of Pioneer Parent in the successful defense of any action,
suit or proceeding, is asserted by such director, officer or controlling person
in connection with the securities being registered, Pioneer Parent will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the
Securities Act of 1933 and will be governed by the final adjudication of such
issue.

     Pioneer Parent hereby undertakes:

     (1) That, for purposes of determining any liability under the Securities
Act of 1933, each filing of Pioneer Parent's annual report pursuant to Section
13(a) or 15(d) of the Securities Exchange Act of 1934 (and, where applicable,
each filing of an employee benefit plan's annual report pursuant to Section
15(d) of the Securities Exchange Act of 1934) that is incorporated by reference
in the registration statement shall be deemed to be a new registration statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be the initial bona fide offering thereof;

     (2) That prior to any public reoffering of the securities registered
hereunder through use of a prospectus which is a part of this registration
statement by any person or party who is deemed to be an underwriter within the
meaning of Rule 145(c), Pioneer Parent undertakes that such reoffering
prospectus will contain the information called for by the applicable
registration form with respect to reofferings by persons who may be deemed
underwriters, in addition to the information called for by the other items of
the applicable form;


     (3) That every prospectus: (a) that is filed pursuant to paragraph (3)
immediately preceding, or (b) that purports to meet the requirements of Section
10(a)(3) of the Securities Exchange Act of 1934 and is used in connection with
an offering of securities subject to Rule 415, will be filed as a part of an
amendment to the registration statement and will not be used until such
amendment is effective, and that, for purposes of determining any liability
under the Securities Act of 1933, each such post-effective amendment shall be
deemed to be a new registration statement relating to the securities offered
therein, and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof;

     (4) To respond to requests for information that is incorporated by
reference into the prospectus pursuant to Items 4, 10(b), 11 or 13 of Form S-4,
within one business day of receipt of such request, and to send the incorporated
documents by first class mail or other equally prompt means. This includes
information contained in documents filed subsequent to the effective date of the
registration statement through the date of responding to the request; and

     (5) To supply by means of a post-effective amendment all information
concerning a transaction, and the company being acquired involved therein, that
was not the subject of and included in the registration statement when it became
effective.




                                      II-9
   1758
                                   SIGNATURES


     Pursuant to the requirements of the Securities Act of 1933, Pioneer Natural
Resources Company has duly caused this registration statement to be signed on
its behalf by the undersigned, thereunto duly authorized, in the City of Irving,
State of Texas, on June 29, 2001.


                            PIONEER NATURAL RESOURCES COMPANY



                            By: /s/ SCOTT D. SHEFFIELD
                               -------------------------------------------------
                               Scott D. Sheffield
                               Chairman of the Board of Directors, President and
                               Chief Executive Officer


     Pursuant to the requirements of the Securities Act of 1933, as amended,
this registration statement has been signed by the following persons in the
capacities and on the dates indicated.




               SIGNATURE                                  TITLE                                 DATE
               ---------                                  -----                                 ----
                                                                                      
                                         Chairman of the Board of Directors, President
                                         and Chief Executive Officer (principal executive
                  *                      officer)                                           June 29, 2001
------------------------------------
Scott D. Sheffield
                                         Executive Vice President and Chief Financial
                  *                      Officer (principal financial officer)              June 29, 2001
------------------------------------
Timothy L. Dove
                                         Vice President and Chief Accounting Officer
                  *                      (principal accounting officer)                     June 29, 2001
------------------------------------
Richard P. Dealy

                  *                      Director                                           June 29, 2001
------------------------------------
James R. Baroffio

                  *                      Director                                           June 29, 2001
------------------------------------
R. Hartwell Gardner

                  *                      Director                                           June 29, 2001
------------------------------------
James L. Houghton

                  *                      Director                                           June 29, 2001
------------------------------------
Jerry P. Jones

                  *                      Director                                           June 29, 2001
------------------------------------
Charles E. Ramsey, Jr.

*By: /s/ MARK L. WITHROW
     -------------------------------
       Attorney-in-fact
       Mark L. Withrow





                                     II-10
   1759
                               INDEX TO EXHIBITS




   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         2.1        Agreement and Plan of Merger dated as of       , 2001, among
                    Pioneer Parent, Pioneer USA and the partnerships named
                    therein (included as Appendix F to the proxy
                    statement/prospectus forming a part of this Registration
                    Statement).

         3.1        Amended and Restated Certificate of Incorporation of Pioneer
                    Parent (incorporated by reference to Exhibit 3.1 to Pioneer
                    Parent's Registration Statement on Form S-4 dated June 27,
                    1997, Registration No. 333-26951).

         3.2        Restated Bylaws of Pioneer Parent (incorporated by reference
                    to Exhibit 3.2 to Pioneer Parent's Registration Statement on
                    Form S-4 dated June 27, 1997, Registration No. 333-26951).

         3.3        Certificate of Designations of Special Preferred Voting
                    Stock (incorporated by reference to Exhibit 3.3 of Pioneer
                    Parent's Registration Statement on Form S-3, Registration
                    No. 333-42315, filed with the SEC on December 17, 1997).

         3.4        Terms and Conditions of Exchangeable Shares (incorporated by
                    reference to Annex F to the Definitive Joint Management
                    Information Circular and Proxy Statement of Pioneer Parent
                    and Chauvco, File No. 001-13245, filed with the SEC on
                    November 17, 1997).

         4.1        Form of Certificate of Common Stock, par value $.01 per
                    share, of Pioneer Parent (incorporated by reference to
                    Exhibit 4.1 to Pioneer Parent's Registration Statement on
                    Form S-4 dated June 27, 1997, Registration No. 333-26951).

         4.2        Form of Certificate of Special Preferred Voting Stock
                    (incorporated by reference to Exhibit 4.1 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         4.3        Form of Certificate of Exchangeable Shares (incorporated by
                    reference to Exhibit 4.2 to Pioneer Parent's Current Report
                    on Form 8-K, File No. 001-13245, filed with the SEC on
                    January 2, 1998).

         5.1*       Form of opinion of Vinson & Elkins L.L.P. as to the legality
                    of the securities to be registered.

         8.1*       Form of opinion of Vinson & Elkins L.L.P., regarding tax
                    matters.

         8.2        Form of opinion of      , as special legal counsel to the
                    limited partners, regarding tax matters as required by the
                    partnership agreement of each partnership (included as
                    Exhibit A to Appendix E to the proxy statement/prospectus
                    forming a part of this Registration Statement).

         9.1        Voting and Exchange Trust Agreement dated as of December 18,
                    1997, among Pioneer Parent, Pioneer Natural Resources
                    (Canada) Ltd. and Montreal Trust Company of Canada, as
                    trustee (incorporated by reference to Exhibit 2.4 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         10.1       Indenture dated July 2, 1996, among Pioneer USA (formerly
                    Mesa Operating Co. ("MOC")), as issuer, Pioneer Parent, as
                    guarantor, and Harris Trust and Savings Bank, as trustee,
                    relating to the 11-5/8% Senior Subordinated Discount Notes
                    Due 2006 (incorporated by reference to Exhibit 4.17 to MESA
                    Inc.'s Quarterly Report on Form 10-Q for the period ended
                    June 30, 1996).





   1760



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.2       First Supplemental Indenture dated as of April 15, 1997,
                    among Pioneer USA (formerly MOC), as issuer, MESA Inc.
                    ("Mesa"), the subsidiary guarantors named therein, Pioneer
                    Parent and Harris Trust and Savings Bank, as trustee, with
                    respect to the indenture identified above as Exhibit 10.1
                    (incorporated by reference to Exhibit 10.1 to Pioneer
                    Parent's Quarterly Report on Form 10-Q for the period ended
                    September 30, 1997, File No. 001-13245).

         10.3       Second Supplemental Indenture dated as of August 7, 1997,
                    among Pioneer USA (formerly MOC), as issuer, Mesa, the
                    subsidiary guarantors named therein, Pioneer Parent and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.1 (incorporated
                    by reference to Exhibit 10.2 to Pioneer Parent's Quarterly
                    Report on Form 10-Q for the period ended September 30, 1997,
                    File No. 001-13245).

         10.4       Third Supplemental Indenture dated as of December 18, 1997,
                    among Pioneer USA, the subsidiary guarantors named therein,
                    Pioneer Parent and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.1 (incorporated by reference to Exhibit 10.12 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.5       Fourth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer USA (formerly MOC), Pioneer Parent, Pioneer
                    NewSub1, Inc. and Harris Trust and Savings Bank, as trustee,
                    with respect to the indenture identified above as Exhibit
                    10.1 (incorporated by reference to Exhibit 10.13 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         10.6       Fifth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer NewSub1, Inc. (as successor to Pioneer USA),
                    Pioneer Parent, Pioneer DebtCo., Inc. and Harris Trust and
                    Savings Bank, as trustee, with respect to the indenture
                    identified above as Exhibit 10.1 (incorporated by reference
                    to Exhibit 10.14 to Pioneer Parent's Current Report on Form
                    8-K, File No. 001-13245, filed with the SEC on January 2,
                    1998).

         10.7       Sixth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer DebtCo. Inc. (as successor to Pioneer NewSub1,
                    Inc.), Pioneer Parent, and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.1 (incorporated by reference to Exhibit 10.15 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.8       Indenture dated July 2, 1996, among Pioneer USA (formerly
                    MOC), as issuer, Pioneer Parent (as Mesa's successor), as
                    guarantor, and Harris Trust and Savings Bank, as trustee,
                    relating to the 10-5/8% Senior Subordinated Notes Due 2006
                    (incorporated by reference to Exhibit 4.18 to Mesa's
                    Quarterly Report on Form 10-Q for the period ended June 30,
                    1996).

         10.9       First Supplemental Indenture dated as of April 15, 1997,
                    among Pioneer USA (formerly MOC), as issuer, Mesa, the
                    subsidiary guarantors named therein, Pioneer Parent and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.8 (incorporated
                    by reference to Exhibit 10.3 to Pioneer Parent's Quarterly
                    Report on Form 10-Q for the period ended September 30, 1997,
                    File No. 001-13245).

         10.10      Second Supplemental Indenture dated as of August 7, 1997,
                    among Pioneer USA (formerly MOC), as issuer, Mesa, the
                    subsidiary guarantors named therein, Pioneer Parent and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.8 (incorporated
                    by reference to Exhibit 10.4 to Pioneer Parent's Quarterly
                    Report on Form 10-Q for the period ended September 30, 1997,
                    File No. 001-13245).





   1761



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.11      Third Supplemental Indenture dated as of December 18, 1997,
                    among Pioneer USA, the subsidiary guarantors named therein,
                    Pioneer Parent and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.8 (incorporated by reference to Exhibit 10.6 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.12      Fourth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer USA, Pioneer Parent, Pioneer NewSub1, Inc. and
                    Harris Trust and Savings Bank, as trustee, with respect to
                    the indenture identified above as Exhibit 10.8 (incorporated
                    by reference to Exhibit 10.7 to Pioneer Parent's Current
                    Report on Form 8-K, File No. 001-13245, filed with the SEC
                    on January 2, 1998).

         10.13      Fifth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer NewSub1, Inc. (as successor to Pioneer USA),
                    Pioneer Parent, Pioneer DebtCo, Inc. and Harris Trust and
                    Savings Bank, as trustee, with respect to the indenture
                    identified above as Exhibit 10.8 (incorporated by reference
                    to Exhibit 10.8 to Pioneer Parent's Current Report on Form
                    8-K, File No. 001-13245, filed with the SEC on January 2,
                    1998).

         10.14      Sixth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer DebtCo, Inc. (as successor to Pioneer NewSub1,
                    Inc.), Pioneer Parent and Harris Trust and Savings Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.8 (incorporated by reference to Exhibit 10.9 to
                    Pioneer Parent's Current Report on Form 8-K, File No. 001-
                    13245, filed with the SEC on January 2, 1998).

         10.15      Indenture dated April 12, 1995, between Pioneer USA
                    (successor to Parker & Parsley Petroleum Company ("Parker &
                    Parsley")) and The Chase Manhattan Bank (National
                    Association), as trustee (incorporated by reference to
                    Exhibit 4.1 to Parker & Parsley's Current Report on Form 8-K
                    dated April 12, 1995, File No. 1-10695).

         10.16      First Supplemental Indenture dated as of August 7, 1997,
                    among Parker & Parsley, The Chase Manhattan Bank, as
                    trustee, and Pioneer USA, with respect to the indenture
                    identified above as Exhibit 10.15 (incorporated by reference
                    to Exhibit 10.5 to Pioneer Parent's Quarterly Report on Form
                    10-Q for the period ended September 30, 1997, File No.
                    001-13245).

         10.17      Second Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer USA, Pioneer NewSub1, Inc. and The Chase
                    Manhattan Bank, as trustee, with respect to the indenture
                    identified above as Exhibit 10.15 (incorporated by reference
                    to Exhibit 10.17 to Pioneer Parent's Current Report on Form
                    8-K, File No. 001-13245, filed with the SEC on January 2,
                    1998).

         10.18      Third Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer NewSub1, Inc. (as successor to Pioneer USA),
                    Pioneer DebtCo, Inc. and The Chase Manhattan Bank, as
                    trustee, with respect to the indenture identified above as
                    Exhibit 10.15 (incorporated by reference to Exhibit 10.18 to
                    Pioneer Parent's Current Report on Form 8-K, File No.
                    001-13245, filed with the SEC on January 2, 1998).

         10.19      Fourth Supplemental Indenture dated as of December 30, 1997,
                    among Pioneer DebtCo, Inc. (as successor to Pioneer NewSub1,
                    Inc., as successor to Pioneer USA), Pioneer Parent, Pioneer
                    USA and The Chase Manhattan Bank, as trustee, with respect
                    to the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 10.19 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001- 13245,
                    filed with the SEC on January 2, 1998).





   1762




   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.20      Guarantee dated as of December 30, 1997, by Pioneer USA
                    relating to $150,000,000 in aggregate principal amount of
                    8-7/8% Senior Notes due 2005 and $150,000,000 in aggregate
                    principal amount of 8 1/4% Senior Notes due 2007 issued
                    under the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 10.20 to Pioneer
                    Parent's Current Report on Form 8-K, File No. 001-13245,
                    filed with the SEC on January 2, 1998).

         10.21      Form of 8-7/8% Senior Notes Due 2005 dated as of April 12,
                    1995, in the aggregate principal amount of $150,000,000,
                    together with Officers' Certificate dated April 12, 1995,
                    establishing the terms of the 8-7/8% Senior Notes Due 2005
                    pursuant to the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 4.2 to Parker &
                    Parsley's Quarterly Report on Form 10-Q for the period ended
                    June 30, 1995, File No. 001-10695).

         10.22      Form of 8 1/4% Senior Notes due 2007 dated as of August 22,
                    1995, in the aggregate principal amount of $150,000,000,
                    together with Officers' Certificate dated August 22, 1995,
                    establishing the terms of the 8 1/4% Senior Notes due 2007
                    pursuant to the indenture identified above as Exhibit 10.15
                    (incorporated by reference to Exhibit 1.2 to Parker &
                    Parsley's Current Report on Form 8-K dated August 17, 1995,
                    File No. 001-10695).

         10.23      Indenture dated January 13, 1998, between Pioneer Parent and
                    The Bank of New York, as trustee (incorporated by reference
                    to Exhibit 99.1 to Pioneer Parent's and Pioneer USA's
                    Current Report on Form 8-K, File No. 001-13245, filed with
                    the SEC on January 14, 1998).

         10.24      First Supplemental Indenture dated as of January 13, 1998,
                    among Pioneer Parent, Pioneer USA, as the subsidiary
                    guarantor, and The Bank of New York, as trustee, with
                    respect to the indenture identified above as Exhibit 10.23
                    (incorporated by reference to Exhibit 99.2 to Pioneer
                    Parent's and Pioneer USA's Current Report on Form 8-K, File
                    No. 001-13245, filed with the SEC on January 14, 1998).

         10.25      Form of 6.50% Senior Notes Due 2008 of Pioneer Parent
                    (incorporated by reference to Exhibit 99.3 to Pioneer
                    Parent's and Pioneer USA's Current Report on Form 8-K, File
                    No. 001-13245, filed with the SEC on January 14, 1998).

         10.26      Form of 7.20% Senior Notes Due 2028 of Pioneer Parent
                    (incorporated by reference to Exhibit 99.4 to Pioneer
                    Parent's and Pioneer USA's Current Report on Form 8-K, File
                    No. 001-13245, filed with the SEC on January 14, 1998).

         10.27      Guarantee (2008 Notes) dated as of January 13, 1998, entered
                    into by Pioneer USA (incorporated by reference to Exhibit
                    99.5 to Pioneer Parent's and Pioneer USA's Current Report on
                    Form 8-K, File No. 001-13245, filed with the SEC on January
                    14, 1998).

         10.28      Guarantee (2028 Notes) dated as of January 13, 1998, entered
                    into by Pioneer USA (incorporated by reference to Exhibit
                    99.6 to Pioneer Parent's and Pioneer USA's Current Report on
                    Form 8-K, File No. 001-13245, filed with the SEC on January
                    14, 1998).

         10.29      1991 Stock Option Plan of Mesa (incorporated by reference to
                    Exhibit 10(v) to Mesa's Annual Report on Form 10-K for the
                    period ended December 31, 1991).

         10.30      1996 Incentive Plan of Mesa (incorporated by reference to
                    Exhibit 10.28 to Pioneer Parent's Registration Statement on
                    Form S-4 dated June 27, 1997, Registration No. 333-26951).

         10.31      Parker & Parsley Long-Term Incentive Plan dated February 19,
                    1991 (incorporated by reference to Exhibit 4.1 to Parker &
                    Parsley's Registration Statement on Form S-8, Registration
                    No. 33-38971).





   1763





   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.32      First Amendment to the Parker & Parsley Long-Term Incentive
                    Plan dated August 23, 1991 (incorporated by reference to
                    Exhibit 10.2 to Parker & Parsley's Registration Statement on
                    Form S-1 dated February 28, 1992, Registration No.
                    33-46082).

         10.33      Pioneer Parent's Long-Term Incentive Plan (incorporated by
                    reference to Exhibit 4.1 to Pioneer Parent's Registration
                    Statement on Form S-8, Registration No. 333-35087).

         10.34      First Amendment to Pioneer Parent's Long-Term Incentive
                    Plan, effective as of November 23, 1998 (incorporated by
                    reference to Exhibit 10.72 to Pioneer Parent's Annual Report
                    on Form 10-K for the period ended December 31, 1999, File
                    No. 001-13245.

         10.35      Amendment No. 2 to Pioneer Parent's Long-Term Incentive
                    Plan, effective as of May 20, 1998 (incorporated by
                    reference to Exhibit 10.73 to Pioneer Parent's Annual Report
                    on Form 10-K for the period ended December 31, 1999, File
                    No. 001-13245).

         10.36      Amendment No. 3 to Pioneer Parent's Long-Term Incentive
                    Plan, effective as of February 17, 2000 (incorporated by
                    reference to Exhibit 10.76 to Pioneer Parent's Annual Report
                    on Form 10-K for the period ended December 31, 1999, File
                    No. 001-13245).

         10.37      Pioneer Parent's Employee Stock Purchase Plan (incorporated
                    by reference to Exhibit 4.1 to Pioneer Parent's Registration
                    Statement on Form S-8, Registration No. 333-35165).

         10.38      Amendment No. 1 to Pioneer Parent's Employee Stock Purchase
                    Plan dated December 9, 1998 (incorporated by reference to
                    Pioneer Parent's Annual Report on Form 10-K for the year
                    ended December 31, 1998, File No. 001-13245).

         10.39      Amendment No. 2 to Pioneer Parent's Employee Stock Purchase
                    Plan dated December 14, 1999 (incorporated by reference to
                    Exhibit 10.74 to Pioneer Parent's Annual Report on Form 10-K
                    for the period ended December 31, 1999, File No. 001-13245).

         10.40      Pioneer Parent's Deferred Compensation Retirement Plan
                    (incorporated by reference to Exhibit 4.1 to Pioneer
                    Parent's Registration Statement on Form S-8, Registration
                    No. 333- 39153).

         10.41      Pioneer USA 401(k) Plan (incorporated by reference to
                    Exhibit 4.1 to Pioneer Parent's Registration Statement on
                    Form S-8, Registration No. 333-39249).

         10.42      Pioneer USA Matching Plan (incorporated by reference to
                    Exhibit 10.42 to Pioneer Parent's Annual Report on Form 10-K
                    for the year ended December 31, 1997, File No. 001-13245).

         10.43      Omnibus Amendment to Nonstatutory Stock Option Agreements,
                    included as part of the Parker & Parsley Long-Term Incentive
                    Plan dated as of November 16, 1995, between Parker & Parsley
                    and named executive officers identified on Schedule 1
                    thereto, setting forth additional details relating to the
                    Parker & Parsley Long-Term Incentive Plan (incorporated by
                    reference to Parker & Parsley's Annual Report on Form 10-K
                    for the period ended December 31, 1995, File No. 001-10695).

         10.44      Severance Agreement dated as of August 8, 1997, between
                    Pioneer Parent and Scott D. Sheffield, together with a
                    schedule identifying substantially identical agreements
                    between Pioneer Parent and each of the other named executive
                    officers identified on Schedule I, for the purpose of
                    defining the payment of certain benefits upon the
                    termination of the officer's employment under certain
                    circumstances (incorporated by reference to Exhibit 10.7 to
                    Pioneer Parent's Quarterly Report on Form 10-Q for the
                    period ended September 30, 1997, File No. 001-13245).





   1764



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         10.45      Indemnification Agreement dated as of August 8, 1997,
                    between Pioneer Parent and Scott D. Sheffield, together with
                    a schedule identifying substantially identical agreements
                    between Pioneer Parent and each of Pioneer Parent's other
                    directors and named executive officers identified on
                    Schedule I thereto (incorporated by reference to Exhibit
                    10.8 to Pioneer Parent's Quarterly Report on Form 10-Q for
                    the period ended September 30, 1997, File No. 001-13245).

         10.46      "B" Contract Production Allocation Agreement dated July 29,
                    1991, and effective as of January 1, 1991, between Colorado
                    Interstate Gas Company and Mesa Operating Limited
                    Partnership (incorporated by reference to Exhibit 10(r) to
                    Mesa's Annual Report on Form 10-K for the period ended
                    December 31, 1991).

         10.47      Amendment to "B" Contract Production Allocation Agreement
                    effective as of January 1, 1993, between Colorado Interstate
                    Gas Company and Mesa Operating Limited Partnership
                    (incorporated by reference to Exhibit 10.24 to Mesa's
                    Registration Statement on Form S-1, Registration No.
                    33-51909).

         10.48      Voting and Shareholders Agreement dated as of February 8,
                    2000, among Prize Energy Corp. and its stockholders
                    (incorporated by reference to Exhibit 10.1 to Pioneer
                    Parent's statement on Schedule 13D relating to common stock
                    of Prize Energy Corp., filed with the SEC on February 18,
                    2000, File No. 005-54797).

         10.49      Second Supplemental Indenture dated as of April 11, 2000,
                    among Pioneer Parent, Pioneer USA, as the subsidiary
                    guarantor, and the Bank of New York, as trustee, with
                    respect to the Indenture dated January 13, 1998, between
                    Pioneer Parent and The Bank of New York, as trustee
                    (incorporated by reference to Exhibit 10.1 to Pioneer
                    Parent's Quarterly Report on Form 10-Q, filed with the SEC
                    on May 11, 2000).

         10.50      Form of 9 5/8% Senior Notes Due April 1, 2010 dated as of
                    April 11, 2000, in the aggregate principal amount of
                    $425,000,000, together with Trustee's Certificate of
                    Authentication dated April 11, 2000, establishing the terms
                    of the 9 5/8% Senior Notes Due April 1, 2010 pursuant to the
                    Second Supplemental Indenture identified above as Exhibit
                    10.49 (incorporated by reference to Exhibit 10.2 to Pioneer
                    Parent's Quarterly Report on Form 10-Q, filed with the SEC
                    on May 11, 2000).

         10.51      Guarantee, dated as of April 11, 2000, by Pioneer USA, as
                    the subsidiary guarantor, relating to the $425,000,000
                    aggregate principal amount of 9 5/8% Senior Notes Due
                    April 1, 2010 issued under the Second Supplemental Indenture
                    identified above as Exhibit 10.49 (incorporated by reference
                    to Exhibit 10.3 to Pioneer Parent's Quarterly Report on Form
                    10-Q, filed with the SEC on May 11, 2000).

         10.52      $575,000,000 Credit Agreement dated as of May 31, 2000,
                    among Pioneer Parent, as the borrower, Bank of America,
                    N.A., as the administrative agent, Credit Suisse First
                    Boston, as the documentation agent, The Chase Manhattan
                    Bank, as the syndication agent, and certain lenders
                    (incorporated by reference to Exhibit 10.4 to Pioneer
                    Parent's Quarterly Report on Form 10-Q, filed with the SEC
                    on August 9, 2000).

         10.53      Agreement and Plan of Merger dated as of November 28, 2000,
                    among Pioneer Parent, Pioneer USA, Parker & Parsley
                    Employees Producing Properties 87-A, Ltd., Parker & Parsley
                    Employees Producing Properties 87-B Ltd., P&P Employees
                    Producing Properties 88-A, L.P., P&P Employees 89-A Conv.,
                    L.P., P&P Employees 89-B Conv., L.P., P&P Employees Private
                    89, L.P., P&P Employees 90-A Conv., L.P., P& P Employees
                    90-B Conv., L.P., P&P Employees 90-C Conv., L.P., P&P
                    Employees Private 90, L.P., P&P Employees 90 Spraberry
                    Private Development, L.P., P&P Employees 91-A Conv., L.P.
                    and P&P Employees 91-B Conv., L.P. (incorporated by
                    reference to Exhibit 10.53 to Pioneer Parent's Annual Report
                    on Form 10-K, filed with the SEC on February 27, 2001).





   1765



   EXHIBIT
    NUMBER                                DESCRIPTION
---------------     ------------------------------------------------------------
                 
         23.1       Consent of Vinson & Elkins L.L.P. (included in the opinions
                    filed as Exhibits 5.1 and 8.1 to this Registration
                    Statement).

         23.2       Consent of ______________ (included in the opinion filed as
                    Exhibit 8.2 to this Registration Statement).

         23.3*      Consent of Ernst & Young LLP.

         23.4*      Consent of Williamson Petroleum Consultants, Inc.

         24.1#      Powers of Attorney of directors and officers of Pioneer
                    Parent.

         99.1       Form of opinion of Robert A. Stanger & Co, Inc. (included as
                    Appendix D to the proxy statement/prospectus forming a part
                    of this Registration Statement).

         99.2*      Consent of Robert A. Stanger & Co., Inc.

         99.3*      Form of Certification of Non-Foreign Status for Individual
                    Partners.

         99.4*      Form of Certification of Non-Foreign Status for Individual
                    Partners that are Entities.

         99.5*      Form of Proxy for Special Meeting of Limited Partners of
                    Each of 46 Parker & Parsley Limited Partnerships.

         99.6*      Form of Letter to Custodians and Consent.




--------------------

*  Filed herewith.
#  Previously filed.