EXHIBIT A
JOINT FILING AGREEMENT
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In accordance with Rule 13d-1(k)(l) under the Securities Exchange Act of 1934,
as amended, the undersigned hereby agree to the joint filing of the attached
Schedule 13G, and any and all amendments thereto, and expressly authorize
AMVESCAP PLC, as the ultimate parent company of each of its undersigned
subsidiaries, to file such Schedule 13G, and any and all amendments thereto, on
behalf of each of them.
Dated: December 29, 2005 AMVESCAP PLC
By: /s/ Xxxxx X. Xxxxxx
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Name: Xxxxx X. Xxxxxx
Title: General Counsel
INVESCO Private Capital, Inc.
By: /s/ Xxxxxxx Xxxxx
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Name: Xxxxxxx Xxxxx
Title: General Counsel
INVESCO Institutional (N.A.), Inc.
By: /s/ Xxxxxxx Xxxxx
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Name: Xxxxxxx Xxxxx
Title: General Counsel