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                                                                   EXHIBIT 10.1

                             U.S. $2,817,426,000

                           NATIONAL RURAL UTILITIES
                       COOPERATIVE FINANCE CORPORATION

                         Medium-Term Notes, Series L

                         CALCULATION AGENT AGREEMENT


                    This AGREEMENT dated January 22, 2001, 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 3 World Financial Center, New York, New
             York 10285-0900.

      WHEREAS (A) The Issuer proposes to issue from time to time an aggregate
principal amount of up to $2,817,426,000 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 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 15, 2000, as supplemented by a Prospectus Supplement, dated January
22, 2001, relating to the Notes. The "Description of the Medium-Term Notes"
means









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the terms and conditions of the Notes as set forth in the Prospectus
Supplement, dated January 22, 2001, relating to 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 January 22,
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 practicable 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 January 22, 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

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periods for each interest period and the relevant Interest Payment Date.

             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

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             (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 upon anything contained in a Floating Rate Note, the
      Description of 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 January 22,
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

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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 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

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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 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 communication 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 3 World
Financial Center, New York, New York 10285, Attention: Medium-Term Note
Department; and in the case of the Trustee,

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to The Bank of New York, 101 Barclay Street, 21W, New York, New York 10286,
Attention: Corporate Trustee Administration Department or, in any case, to any
other address of which the party receiving notice shall have notified the party
giving such notice in writing.

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      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.

      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