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: December 9, 2004

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


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

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

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

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

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


                              *By: /s/ ▇▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                   ---------------------------------------------
                                   ▇▇▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇
                                   Chief Financial Officer of Artisan Investment
                                   Corporation
                                   Attorney-in-Fact for ▇▇▇▇▇▇ ▇. ▇▇▇▇▇▇▇
                                   Attorney-in-Fact for ▇▇▇▇▇▇▇ ▇▇▇▇▇▇ ▇▇▇▇▇▇▇

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