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                                                                   EXHIBIT 10.36
                            THIRD AMENDMENT AGREEMENT


                  This Third Amendment Agreement dated as of March 27, 2001 is
entered into between Ceridian Canada Ltd. (the "BORROWER") and Canadian Imperial
Bank of Commerce (the "BANK").


RECITALS

A. Reference is made to the Credit Agreement dated as of March 2, 1998 between
the Borrower and the Bank (as amended, the "CREDIT AGREEMENT"). Capitalized
terms used but not otherwise defined herein have the meanings assigned to them
in the Credit Agreement;

B. Ceridian Corporation ("OLD CERIDIAN") guaranteed the obligations of the
Borrower to the Bank pursuant to a guarantee dated as of March 2, 1998 (the
"ORIGINAL GUARANTEE");

C. The Borrower is a wholly-owned subsidiary of Ceridian Canada Holdings, Inc.;

D. Pursuant to a transaction scheduled to be completed on or about March 30,
2001 (the "SEPARATION"), Old Ceridian will transfer the majority of its assets,
liabilities and operations (excluding those assets, liabilities and operations
related to its media audience measurement business) and shares of its
subsidiaries, including the shares of Ceridian Canada Holdings, Inc. to New
Ceridian Corporation (the "GUARANTOR"), which is currently a wholly owned
subsidiary of Old Ceridian;

E. Immediately following the Separation, Old Ceridian will change its name to
Arbitron Inc. and New Ceridian will change its name to Ceridian Corporation;

F. The Borrower has requested certain amendments to the Credit Agreement and the
Bank has agreed to such amendments on the terms and conditions contained herein.



                  NOW THEREFORE, in consideration of the mutual agreements
herein contained and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

1. AMENDMENTS TO CREDIT AGREEMENT. Effective as of the Amendment Effective Date
(as defined below), the Credit Agreement shall be amended as follows:

         (a)      All references to the "Guarantor" contained in the Credit
                  Agreement and all documents delivered pursuant thereto shall
                  mean New Ceridian;

         (b)      Clause (i) of the definition of "Guarantor Credit Agreement"
                  shall be deleted and replaced with the following:


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                           the Credit Agreement dated as of January 31, 2001,
                           among the Guarantor, as borrower, Bank of America
                           N.A., as administrative agent, the other lenders
                           party thereto and Banc of America Securities LLC, as
                           arranger and manager;

         (c)      The definition of "Facility A Limit" and "Facility A Maturity
                  Date" contained in Appendix "A" shall be deleted and replaced
                  with the following:

                  "Facility A Limit" means the amount of Cdn.$20,000,000 or the
                  U.S. Dollar Equivalent thereof.

                  "Facility A Maturity Date" means May 31, 2001.

         (d)      The following definition shall be added to Appendix "A" in the
                  proper alphabetical order:

                  "Applicable Margin" means 0.625%, provided that the Applicable
                  Margin shall be reduced to 0.50% for so long as the Guarantor
                  shall have a Debt Rating of BBB+ or better. Any change in the
                  Applicable Margin resulting from a publicly announced change
                  in the Debt Rating shall be effective on and as of the date of
                  such public announcement of any Debt Rating that indicates a
                  different Applicable Margin in accordance with this
                  definition;

                  "Applicable Stamping Fee" means 0.625%, provided that the
                  Applicable Stamping Fee shall be reduced to 0.50% for so long
                  as the Guarantor shall have a Debt Rating of BBB+ or better.
                  Any change in the Applicable Stamping Fee resulting from a
                  publicly announced change in the Debt Rating shall be
                  effective on and as of the date of such public announcement of
                  any Debt Rating that indicates a different Applicable Stamping
                  Fee in accordance with this definition;

                  "Debt Rating" means, as of any date of determination, the
                  rating as determined by Standard & Poor's Rating Services, a
                  division of the McGraw-Hill Companies, of the Guarantor's
                  non-credit-enhanced, senior unsecured long-term debt;

                  "Facility A Extension Date" has the meaning ascribed thereto
                  in Section 3.10.

         (e)      Section 2.1 is amended by deleting clause (a) and replacing it
                  with the following:

                  (a)      an extendible, revolving operating facility
                           ("Facility A") in the amount of the Facility A Limit;

         (f)      Article 3 shall be amended by adding the following Section as
                  Section 3.10:

                  3.10 FACILITY A EXTENSION. By notice in writing to the Bank
                  given not more than 90 days and not less than 30 days prior to
                  the Facility A Maturity Date, the Borrower may request an
                  extension of the availability of Facility A for a period of up
                  to 364 days from the Facility A Maturity Date (the last day of
                  such period, the




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                  "Facility A Extension Date"). The consent of the Bank to such
                  extension shall be in its sole and absolute discretion. If the
                  Bank consents to such extension, the Facility A Maturity Date
                  shall be extended until the Facility A Extension Date, with
                  effect on the Facility A Maturity Date.

         (g)      Section 4.1 shall be amended by deleting clauses (c), (d) and
                  (e) and substituting the following:

                  (c)      in the case of each LIBO Loan, the LIBO Rate plus the
                           Applicable Margin;

                  (d)      in the case of Banker's Acceptances, the Stamping Fee
                           at the Applicable Stamping Fee; and

                  (e)      in the case of each Letter of Credit, 0.5% per annum
                           of the amount of the Letter of Credit, payable in
                           advance.

         (h)      The address of the Borrower contained in Section 10.2 shall be
                  deleted and replaced with the following address:

                  3311 East Old Shakopee Road,
                  Minneapolis, MN  55425-1640  U.S.A.

         (i)      The address of the Bank shall be deleted and replaced with the
                  following address:

                  Winnipeg Commercial Banking Centre
                  500 - One Lombard Place, P.O. Box 814
                  Winnipeg, MB  R3C 2P3  Canada

                  Telephone:  (204) 944-5033
                  Facsimile:  (204) 943-8347
                  Attention:  Director


2. RELEASE. Effective on the Amendment Effective Date, the Bank releases and
discharges Old Ceridian from its obligations under the Original Guarantee. The
Bank acknowledges that this release and discharge shall be enforceable by and
enure to the benefit of Old Ceridian as if Old Ceridian were a party to this
Agreement.

3. CONDITIONS TO EFFECTIVENESS. This Agreement shall become effective on the
date (the "AMENDMENT EFFECTIVE DATE") of the satisfaction in full of the
following conditions precedent:

         (a)      The Separation shall have been completed;

         (b)      The Bank shall have received, in form and substance
                  satisfactory to the Bank,

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                  (i)      a Guarantee dated as of the date hereof from New
                           Ceridian;

                  (ii)     certificates of a senior officer of each of the
                           Borrower and New Ceridian setting forth specimen
                           signatures of the individuals authorized to sign this
                           agreement and the Guarantee, as applicable, certified
                           copies of the resolutions or other corporate
                           proceedings of the Obligors authorizing the
                           transactions under this agreement and the Guarantee,
                           as applicable, and other corporate and factual
                           matters relevant to the transactions under the Credit
                           Agreement;

                  (iii)    an opinion of Canadian counsel to the Borrower and
                           New Ceridian, addressed to the Bank, in form and
                           substance satisfactory to the Bank;

                  (iv)     an opinion of in-house counsel to New Ceridian,
                           addressed to the Bank, in form and substance
                           satisfactory to the Bank; and

                  (v)      an opinion of United States counsel to New Ceridian,
                           addressed to the Bank, in form and substance
                           satisfactory to the Bank.

         (c)      The Bank shall have received an amendment fee of $15,000.

4. REPRESENTATIONS. The Borrower represents and warrants to the Bank that, as of
the Amendment Effective Date:

         (a)      This Agreement has been duly authorized, executed and
                  delivered by the Borrower, and the Credit Agreement, as
                  amended hereby, constitutes a legal, valid and binding
                  obligation of the Borrower, enforceable in accordance with its
                  terms, subject to applicable bankruptcy, insolvency,
                  reorganization, moratorium or other laws affecting creditor's
                  rights generally and subject to general principles of equity,
                  regardless of whether considered in a proceeding in equity or
                  at law;

         (b)      No Default has occurred and is continuing; and

         (c)      The representations and warranties of the Borrower contained
                  in Section 6.1 of the Credit Agreement, the representations
                  and warranties of New Ceridian contained in Article V of the
                  Guarantor Credit Agreement, and the representations of New
                  Ceridian contained in the Guarantee are true and correct in
                  all material respects on and as of the date hereof, except to
                  the extent they refer to filings made by New Ceridian with the
                  United States Securities and Exchange Commission ("SEC"), in
                  which case they shall be deemed amended to include all filings
                  made by New Ceridian with the SEC to the date hereof.

5. CREDIT AGREEMENT IN EFFECT. Except as specifically stated herein, the Credit
Agreement shall continue in full force and effect in accordance with the
provisions thereof and all Security Documents issued or granted in connection
therewith shall continue in full force and effect. After this Agreement becomes
effective as provided herein, any reference to the Credit Agreement shall refer
to the Credit Agreement as amended hereby.



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6. APPLICABLE LAW. This Agreement shall be construed in accordance with and
governed by the laws of Ontario.

7. COUNTERPARTS. This Agreement may be executed in any number of counterparts,
each of which shall be an original but all of which, when taken together, shall
constitute one instrument. Delivery of an executed counterpart of a signature
page of this Agreement by telecopy shall be effective as delivery of a manually
executed counterpart of this Agreement.

                  IN WITNESS WHEREOF, the parties hereto have caused this Third
Amendment Agreement to be duly executed by their respective authorized officers
as of the date first above written.


                                       CANADIAN IMPERIAL BANK OF COMMERCE



                                       By:    /s/ Ron D. Craven
                                          --------------------------------------
                                       Name:  Ron D. Craven
                                       Title: Manager Commercial Credit

                                       By:    /s/ Ken Hargreaves
                                            ------------------------------------
                                       Name:  Ken Hargreaves
                                       Title: Director


                                       CERIDIAN CANADA LTD.


                                       By:  /s/ John H. Grierson
                                       Name:  John H. Grierson
                                       Title:  Vice President and Treasurer

                                       By:      /s/ Gary M. Nelson
                                       Name:  Gary M. Nelson
                                       Title:  Vice President and Secretary