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                                                                    EXHIBIT 10.1


                                                                  CONFORMED COPY





                               U.S. $2,016,856,000

                            NATIONAL RURAL UTILITIES
                         COOPERATIVE FINANCE CORPORATION

                           Medium-Term Notes, Series C


                           CALCULATION AGENT AGREEMENT


                                This AGREEMENT dated June 15, 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 $2,016,856,000 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

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the Prospectus, dated June 13, 2001, as supplemented by a Prospectus Supplement,
dated June 14, 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 June 14, 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 June 14, 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 June 14, 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).

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                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.

                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;

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                (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 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 June 14, 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.

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                (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 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

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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 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

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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, to it at
The Bank of New York, 101 Barclay Street, 21W, New York, New York 10286,
Attention: Trust Administrator 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/ Erin Callan
                                          ---------------------------

                                          Name:  Erin Callan
                                          Title: Managing Director