JOINT FILING AGREEMENT

                                                                       EXHIBIT 1

                             JOINT FILING AGREEMENT

     The undersigned hereby agree to the joint filing of the Schedule 13G to
which this Agreement is attached.

Dated: January 26, 2005

                                   ARTISAN INVESTMENT CORPORATION
                                   for itself and as general partner of
                                   ARTISAN PARTNERS LIMITED PARTNERSHIP


                                   By: Xxxxxxxx X. Xxxxxx*
                                       -----------------------------------------


                                   XXXXXX X. XXXXXXX


                                   Xxxxxx X. Xxxxxxx*
                                   ---------------------------------------------


                                   XXXXXXX XXXXXX XXXXXXX


                                   Xxxxxxx Xxxxxx Xxxxxxx*
                                   ---------------------------------------------


                                   ARTISAN FUNDS, INC.


                                   By: Xxxxxxxx X. Xxxxxx*
                                       -----------------------------------------


                                   *By: /s/ Xxxxxxxx X. Xxxxxx
                                        ----------------------------------------
                                        Xxxxxxxx X. Xxxxxx
                                        Chief Financial Officer of Artisan
                                        Investment Corporation
                                        Attorney-in-Fact for Xxxxxx X. Xxxxxxx
                                        Attorney-in-Fact for Xxxxxxx Xxxxxx
                                        Xxxxxxx
                                        Chief Financial Officer and Treasurer
                                        of Artisan Funds, Inc.

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