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                                                                  CONFORMED COPY
                               U.S. $2,677,267,000

                            NATIONAL RURAL UTILITIES
                        COOPERATIVE FINANCE CORPORATION

                           Medium-Term Notes, Series C


                           CALCULATION AGENT AGREEMENT

                                             This AGREEMENT dated January 15,
                                    2002, between National Rural Utilities
                                    Cooperative Finance Corporation, a District
                                    of Columbia cooperative association
                                    (hereinafter called the "Issuer"), whose
                                    principal office is at Woodland Park, 2201
                                    Cooperative Way, Herndon, Virginia 20171,
                                    and Lehman Brothers Inc., a Delaware
                                    corporation (hereinafter sometimes called
                                    the "Calculation Agent" which term shall,
                                    unless the context shall otherwise require,
                                    include its successors and assignees), whose
                                    principal office is at 101 Hudson Street,
                                    Jersey City, NJ 07302.

                           WHEREAS (A) The Issuer proposes to issue from time to
                  time an aggregate principal amount of up to $2,677,267,000 of
                  Medium-Term Notes, Series C (the "Notes") entitled to the
                  benefits of the Indenture dated as of December 15, 1987 (as
                  supplemented by the First Supplemental Indenture dated as of
                  October 1, 1990, and as it may be supplemented or amended from
                  time to time, the "Indenture"), between the Issuer and The
                  Bank of New York, as successor trustee;

                           (B) Each Note will bear interest at either (a) a
                  fixed rate or (b) a floating rate determined by reference to
                  an interest rate formula (the "Floating Rate Notes");

                           NOW IT IS HEREBY AGREED THAT,

                           1. Terms defined in the "Description of Debt
                  Securities" and "Description of the Medium-Term Notes" shall
                  bear the same meanings herein unless the context otherwise
                  requires. The "Description of Debt Securities" means the terms
                  and conditions of the Notes as set forth in the Prospectus,
                  dated December 5, 2001, as supplemented by a Prospectus
                  Supplement, dated December 5, 2001, relating to the Notes. The
                  "Description of the Medium-Term Notes" means the terms and
                  conditions of the Notes as set forth in the Prospectus
                  Supplement, dated December 5, 2001, relating to
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                  the Notes. Such Prospectus Supplement will be supplemented or
                  amended by one or more Pricing Supplements (each a
                  "Supplement") setting forth additional terms and conditions of
                  the Notes.

                           2. The Issuer hereby appoints Lehman Brothers Inc. as
                  Calculation Agent for the Notes, upon the terms and subject to
                  the conditions herein mentioned, and Lehman Brothers Inc.
                  hereby accepts such appointment. The Calculation Agent shall
                  act as an agent of the Issuer for the purpose of determining
                  the interest rate of the Floating Rate Notes in accordance
                  with the Description of the Medium-Term Notes and the
                  provisions of this Agreement.

                           3. The Calculation Agent shall calculate the
                  applicable interest rates for the Floating Rate Notes in
                  accordance with the provisions set forth in the Prospectus
                  Supplement relating to the Notes dated December 5, 2001, under
                  the heading "Description of the Medium-Term Notes--Floating
                  Rate Notes" which provisions are incorporated by reference
                  herein as if set forth in full in this Agreement.

                           4. In no event shall the interest rate be less than
                  the floor, if any, or more than the ceiling, if any,
                  designated in the applicable Supplement.

                           5. The Calculation Agent will, as soon as practi-
                  cable after (i) 3:00 p.m., New York City time, on the
                  Calculation Date pertaining to each Interest Determination
                  Date relating to Commercial Paper Rate Notes, Fed Funds Rate
                  Notes, CD Rate Notes and Treasury Rate Notes or (ii) 11:00
                  a.m., London time, on each Interest Determination Date
                  relating to LIBOR Notes, determine (and notify the Issuer and
                  the Trustee of) the interest rate applicable during the next
                  succeeding interest period (if the interest rate cannot be
                  determined in accordance with the provisions set forth in the
                  Prospectus Supplement relating to the Notes dated December 5,
                  2001, in clause (i) under the heading "Description of the
                  Medium-Term Notes--Floating Rate Notes--LIBOR", the
                  Calculation Agent agrees to determine (and notify the Issuer
                  and Trustee of) the interest rate in accordance with the
                  provisions in clause (ii) of such heading).

                           6. As soon as determined after each Interest
                  Determination Date, the Calculation Agent will cause to be
                  forwarded to the Issuer, the Trustee and the Paying Agent
                  information regarding the interest rates and the interest
                  periods for each interest period and the relevant Interest
                  Payment Date.
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                           7. The Issuer will pay such compensation as shall be
                  agreed upon and the expenses, including reasonable counsel
                  fees, properly incurred by the Calculation Agent in connection
                  with its duties hereunder, upon receipt of such invoices as
                  the Issuer shall reasonably require.

                           8. The Issuer will indemnify the Calculation Agent
                  against any losses, liabilities, costs, claims, actions or
                  demands which it may incur or sustain or which may be made
                  against it in connection with its appointment or the exercise
                  of its powers and duties hereunder as well as the reasonable
                  costs, including the expenses and fees of counsel in defending
                  any claim, action or demand, except such as may result from
                  the negligence, wilful default or bad faith of the Calculation
                  Agent or any of its employees. The Calculation Agent shall
                  incur no liability and shall be indemnified and held harmless
                  by the Issuer for, or in respect of, any actions taken or
                  suffered to be taken in good faith by the Calculation Agent in
                  reliance upon (i) the written opinion or advice of counsel or
                  (ii) written instructions from the Issuer.

                           9. The Calculation Agent accepts its obligations
                  herein (and agrees to act in good faith in the performance of
                  its obligations) set forth upon the terms and conditions
                  hereof, including the following, to all of which the Issuer
                  agrees:

                                    (i) in acting under this Agreement and in
                           connection with the Notes, the Calculation Agent,
                           acting as agent for the Issuer, does not assume any
                           obligation towards, or any relationship of agency or
                           trust for or with, any of the holders of the Notes;

                                    (ii) unless herein otherwise specifically
                           provided, any order, certificate, notice, request or
                           communication from the Issuer made or given under any
                           provision of this Agreement shall be sufficient if
                           signed by any person whom the Calculation Agent
                           reasonably believes to be a duly authorized officer
                           of the Issuer;

                                    (iii) the Calculation Agent shall be
                           obligated to perform only such duties as are set
                           forth specifically herein and any duties necessarily
                           incidental thereto; and

                                    (iv) the Calculation Agent shall be
                           protected and shall incur no liability for or in
                           respect of any action taken or omitted to be taken by
                           it in reliance
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                           upon anything contained in a Floating Rate Note, the
                           Description of Debt Securities, the Description of
                           the Medium-Term Notes or one or more Prospectus
                           Supplements.

                           10. (A) The Issuer agrees to notify the Calculation
                  Agent at least five London Business Days prior to the issuance
                  of any LIBOR Note. The Calculation Agent agrees to select four
                  Reference Banks prior to the issuance of the first LIBOR Note
                  by the Issuer; to make all appropriate arrangements for such
                  banks to act as Reference Banks; and to notify the Issuer, the
                  Trustee and each of the Agents as to the names and addresses
                  of such Reference Banks. The Calculation Agent covenants that,
                  for so long as it is required so to do in accordance with the
                  applicable Description of the Medium-Term Notes, it shall
                  ensure that there shall at all times be four Reference Banks.
                  Forthwith upon any change in the identity of the Reference
                  Banks, the Calculation Agent shall notify the Issuer, the
                  Trustee and the Agents of such change. If fewer than two
                  Reference Banks are quoting, the Calculation Agent agrees to
                  select three major banks in The City of New York in accordance
                  with the applicable Description of the Medium-Term Notes. The
                  Calculation Agent shall not be responsible to the Issuer or
                  any third party for any failure of the Reference Banks to
                  fulfill their duties or meet their obligations as Reference
                  Banks or as a result of the Calculation Agent having acted
                  (except in the event of negligence, wilful default or bad
                  faith) on any certificate given by any Reference Bank which
                  subsequently may be found to be incorrect.

                           (B) If necessary, in accordance with the provisions
                  set forth in the Prospectus Supplement relating to the Notes
                  dated December 5, 2001, under the Heading "Description of the
                  Medium-Term Notes--Floating Rate Notes--Prime Rate", the
                  Calculation Agent agrees to select a substitute major bank or
                  trust company (meeting the requirements specified under such
                  heading). The Calculation Agent shall not be responsible to
                  the Issuer or any third party for the failure of such bank or
                  trust company to fulfill any duty or obligation contemplated
                  under such heading.

                           (C) Except as provided below, the Calculation Agent
                  may at any time resign as Calculation Agent by giving written
                  notice to the Issuer and the Trustee of such intention on its
                  part, specifying the date on which its desired resignation
                  shall become effective, provided that such notice shall be
                  given not less than two months prior to the said effective
                  date unless the Issuer and the Trustee otherwise agree in
                  writing. Except as provided below, the
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                  Calculation Agent may be removed by the filing with it of an
                  instrument in writing signed by the Issuer specifying such
                  removal and the date when it shall become effective (such
                  effective date being at least 20 days after said filing). Such
                  resignation or removal shall take effect upon:

                                    (i) the appointment by the Issuer as
                           hereinafter provided of a successor Calculation Agent
                           approved by the Trustee, which shall be a responsible
                           financial firm or institution having an established
                           place of business in The City of New York;

                                    (ii) the acceptance of such appointment by
                           such successor Calculation Agent; and

                                    (iii) the giving of notice of such
                           appointment to the holders of the Notes, provided
                           that if the Calculation Agent fails duly to establish
                           the amount of interest for any interest period, such
                           removal will take effect immediately upon such
                           appointment of, and acceptance thereof by, a
                           successor Calculation Agent approved by the Trustee
                           and qualified as aforesaid, in which event notice of
                           such appointment shall be given to the holders of the
                           Notes as soon as practicable thereafter. Upon its
                           resignation or removal becoming effective, the
                           retiring Calculation Agent shall be entitled to the
                           payment of its compensation and the reimbursement of
                           all expenses incurred by such retiring Calculation
                           Agent pursuant to paragraph 7 hereof.

                           (D) If at any time the Calculation Agent shall resign
                  or be removed, or shall become incapable of acting or shall be
                  adjudged bankrupt or insolvent, or liquidated or dissolved, or
                  an order is made or an effective resolution is passed to wind
                  up the Calculation Agent, or if the Calculation Agent shall
                  file a voluntary petition in bankruptcy or make an assignment
                  for the benefit of its creditors, or shall consent to the
                  appointment of a receiver, administrator or other similar
                  official of all or any substantial part of its property, or
                  shall admit in writing its inability to pay or meet its debts
                  as they mature, or if a receiver, administrator or other
                  similar official of the Calculation Agent or of all or any
                  substantial part of its property shall be appointed, or if any
                  order of any court shall be entered approving any petition
                  filed by or against the Calculation Agent under the provisions
                  of any applicable bankruptcy or insolvency law, or if any
                  public officer shall take charge or control of the Calculation
                  Agent or its property or affairs for the purpose of
                  rehabilitation, conservation or liquidation, then a successor
                  Calculation
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                  Agent, approved by the Trustee, shall be appointed by the
                  Issuer by an instrument in writing filed with the successor
                  Calculation Agent. Upon the appointment as aforesaid of a
                  successor Calculation Agent and acceptance by the latter of
                  such appointment and (except in cases of removal for failure
                  to establish the amount of interest) the giving of notice to
                  the holders of the Notes, the former Calculation Agent shall
                  cease to be Calculation Agent hereunder.

                           (E) Any successor Calculation Agent appointed
                  hereunder shall execute and deliver to its predecessor and the
                  Issuer an instrument, in the form acceptable to the Trustee,
                  accepting such appointment hereunder, and thereupon such
                  successor Calculation Agent, without any further act, deed or
                  conveyance, shall become vested with all the authority,
                  rights, powers, trusts, immunities, duties and obligations
                  of such predecessor with like effect as if originally named as
                  the Calculation Agent hereunder, and such predecessor shall
                  thereupon become obliged to transfer and deliver, and such
                  successor Calculation Agent shall be entitled to receive,
                  copies of any relevant records maintained by such predecessor
                  Calculation Agent.

                           (F) Any corporation into which the Calculation Agent
                  may be merged or converted or any corporation with which the
                  Calculation Agent may be consolidated or any corporation
                  resulting from any merger, conversion or consolidation to
                  which the Calculation Agent shall be a party shall, to the
                  extent permitted by applicable law and provided that it shall
                  be a responsible financial firm or institution having an
                  established place of business in The City of New York, be the
                  successor Calculation Agent under this Agreement without the
                  execution or filing of any paper or any further act on the
                  part of any of the parties hereto. Notice of any such merger,
                  conversion or consolidation shall forthwith be given to the
                  Issuer and the Trustee.

                           11. Any notice required to be given hereunder shall
                  be delivered in person, sent by letter or telex or
                  communicated by telephone (subject, in the case of communi-
                  cation by telephone, to confirmation dispatched within two
                  business days by letter or telex), in the case of the Issuer,
                  to it at Woodland Park, 2201 Cooperative Way, Herndon,
                  Virginia 20171, Attention: Chief Financial Officer; in the
                  case of the Calculation Agent, to it at 101 Hudson Street,
                  Jersey City, New Jersey 07302, Attention: Medium-Term Note
                  Department; and in the case of the Trustee, to it at The Bank
                  of New York, 5 Penn Plaza, New York, New York 10001-1810,
                  Attention: Trust Administrator or, in any case, to any other
                  address of which the party receiving
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                  notice shall have notified the party giving such notice in
                  writing.

                           12. This Agreement may be amended only by a writing
                  duly executed and delivered by each of the parties signing
                  below.

                           13.THE PROVISIONS OF THIS AGREEMENT SHALL BE GOVERNED
                  BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
                  NEW YORK.

                           14. This Agreement may be executed in counterparts
                  and the executed counterparts shall together constitute a
                  single instrument.
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                           IN WITNESS WHEREOF, this Agreement has been executed
                  and delivered as of the day and year first above written.

                                    NATIONAL RURAL UTILITIES COOPERATIVE FINANCE
                                    CORPORATION,

                                    by /s/ Steven L. Lilly
                                      -------------------------------
                                      Name:  Steven L. Lilly
                                      Title: Sr. Vice President &
                                             Chief Financial Officer


                                    LEHMAN BROTHERS INC.,

                                    by  /s/ Greg Hall
                                      -------------------------------
                                      Name:  Greg Hall
                                      Title: Managing Director