AMENDMENT TO 364-DAY CREDIT AGREEMENT


This  Amendment  to 364-Day  Credit  Agreement  (the  "Amendment"),  dated as of
November  18,  1999,  is  between  (i)  FactSet   Research   Systems  Inc.  (the
"Borrower"), and (ii) The Chase Manhattan Bank (the "Bank").

     WHEREAS,  the  Borrower  and the  Bank  are  parties  to a  364-Day  Credit
Agreement dated as of November 20, 1998 (the "Credit Agreement"); and

     WHEREAS,  the Bank and the Borrower desire to amend the Credit Agreement to
extend the Maturity Date.

     NOW, THEREFORE, in consideration of the premises herein contained,  and for
other good and valuable consideration,  receipt of which is acknowledged,  it is
hereby agreed as follows:

     Section 1.  Definitions.  Terms used but not otherwise defined herein shall
have the respective meanings ascribed to such terms in the Credit Agreement.

     Section 2.  Amendment to Section 1.01.  The definition of the term Maturity
Date, in Section 1.01 of the Credit Agreement,  is hereby amended to read in its
entirety as follows:

     "Maturity Date" means November 16, 2000.

     Section 3. Representations.  The Borrower hereby represents and warrants to
the Bank that: (i) the  representations  and warranties set forth in Article III
of the Credit  Agreement are true and correct in all material  respects with the
same  effect  as if  made  on  the  date  hereof,  except  to  the  extent  such
representations  and warranties relate to an earlier date; (ii) before and after
giving effect to this Amendment, no Event of Default or Default has occurred and
is  continuing;  and (iii) the making and  performance  by the  Borrower of this
Amendment have been duly authorized by all necessary corporate action.

     Section 4.  Conditions.  The  amendment  set forth in Section 2 above shall
become  effective on the date first above  written  provided that the Bank shall
have received a counterpart of this Amendment duly executed and delivered by the
Borrower.

     Section 5. Miscellaneous. Except as specifically amended hereby, the Credit
Agreement  shall  continue  in full  force  and  effect in  accordance  with the
provisions  thereof as in existence  on the date hereof.  After the date hereof,
any  reference to "this  Agreement",  "herein",  "hereunder"  and similar  terms
referring  to the  Credit  Agreement  shall be  deemed  to  refer to the  Credit
Agreement as amended hereby. This Amendment (i) shall become effective as of the
date first above written,  (ii) shall be governed by and construed in accordance
with the laws of the State of New York, and (iii) may be executed in counterpart
(and by different parties hereto on different counterparts),  each of which when
taken  together  shall  constitute  a  single  contract.  Should  any  terms  or
provisions  of the  Credit  Agreement  conflict  with the terms  and  provisions
contained in this  Amendment,  the terms and provisions of this Amendment  shall
prevail.


     IN WITNESS WHEREOF,  the parties hereto,  by their officers  thereunto duly
authorized,  have  executed  this  Amendment  as of the day and year first above
written.



FACTSET RESEARCH SYSTEMS INC.               THE CHASE MANHATTAN BANK


By:  ________________________________       By:  _______________________________

Its:  _______________________________       Its:________________________________