
                                                                 EXHIBIT I



                                   JOINT FILING AGREEMENT




        Each of the undersigned hereby agrees that the Schedule 13G filed
   herewith is filed jointly, pursuant to Rule 13d-1(f)(1) of the Securities
   Exchange Act of 1934, as amended on behalf of each of them.


               Dated: February 10, 2000



               AXA Financial, Inc.



               BY:  /s/ Alvin H. Fenichel
                  -------------------------
                  Alvin H. Fenichel
                  Senior Vice President
                  and Controller



        AXA Assurances I.A.R.D. Mutuelle; AXA Assurances Vie Mutuelle; AXA
   Conseil Vie Assurance Mutuelle; AXA Courtage Assurance Mutuelle, as a
   group, and AXA

               Signed on behalf of each of the above entities



               BY:      /s/ Alvin H. Fenichel
                  Alvin H. Fenichel
                  Attorney-in-Fact
                  (Executed pursuant to Powers of Attorney)
