EXHIBIT 1 --------- AGREEMENT AS TO JOINT FILING OF SCHEDULE 13G -------------------------------------------- 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. Date: February 7, 2002 SALOMON SMITH BARNEY HOLDINGS INC. By: /s/ Joseph B. Wollard -------------------------------------------- Name: Joseph B. Wollard Title: Assistant Secretary CITIGROUP INC. By: /s/ Joseph B. Wollard -------------------------------------------- Name: Joseph B. Wollard Title: Assistant Secretary