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                                    EXHIBIT 1
                                    ---------

                  AGREEMENT AS TO JOINT FILING OF SCHEDULE 13G
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Each of the undersigned hereby affirms that it is individually eligible to use
Schedule 13G, and agrees that this Schedule 13G is filed on its behalf.

Dated: February 10, 2003

                      SALOMON SMITH BARNEY INC.


                      By: /s/ Joseph B. Wollard
                         --------------------------------------------
                         Name:   Joseph B. Wollard
                         Title:  Assistant Secretary


                      SALOMON BROTHERS HOLDING COMPANY INC


                      By: /s/ Joseph B. Wollard
                         --------------------------------------------
                         Name:   Joseph B. Wollard
                         Title:  Assistant Secretary


                      SALOMON SMITH BARNEY HOLDINGS INC.


                      By: /s/ Joseph B. Wollard
                         --------------------------------------------
                         Name:   Joseph B. Wollard
                         Title:  Assistant Secretary


                      CITIGROUP INC.


                      By: /s/ Serena D. Moe
                         --------------------------------------------
                         Name:   Serena D. Moe
                         Title:  Assistant Secretary