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.

                              Date: April 8, 2005

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


                                   By: ▇▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇*
                                       -----------------------------------------


                                   ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇


                                   ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇*
                                   ---------------------------------------------


                                   ▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇▇


                                   ▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇▇*
                                   ---------------------------------------------


                                   ARTISAN FUNDS, INC.


                                   By: ▇▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇*
                                       -----------------------------------------


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

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