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*
                                        ----------------------------------------

                                       *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

                                 Page 10 of 12