<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>a2039388zex-99_1.txt
<DESCRIPTION>EXHIBIT 99.1
<TEXT>

<PAGE>


                                    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 16, 2001

                      SALOMON SMITH BARNEY INC.



                      By: /s/  Howard M. Darmstadter
                         --------------------------------------------
                         Name:   Howard M. Darmstadter
                         Title:  Assistant Secretary


                      SALOMON BROTHERS HOLDING COMPANY INC



                      By: /s/ Howard M. Darmstadter
                         --------------------------------------------
                         Name:  Howard M. Darmstadter
                         Title: Assistant Secretary


                      SALOMON SMITH BARNEY HOLDINGS INC.



                      By: /s/ Howard M. Darmstadter
                         --------------------------------------------
                         Name:  Howard M. Darmstadter
                         Title: Assistant Secretary



                      CITIGROUP INC.



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

</TEXT>
</DOCUMENT>
