EXHIBIT I
JOINT FILING AGREEMENT
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Each of the undersigned hereby agrees that the Schedule 13G filed
herewith is filed jointly, pursuant to Rule 13d-1(f)(1) of the Securities
Exchange Act of 1934, as amended on behalf of each of them.
Dated: February 14, 2008
AXA Financial, Inc.
BY: /s/ Xxxxx X. Xxxxxxxx
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Xxxxx X. Xxxxxxxx
Senior Vice President and Controller
AXA Assurances I.A.R.D. Mutuelle; AXA Assurances Vie Mutuelle; AXA
Courtage Assurance Mutuelle, as a group, and AXA
Signed on behalf of each of the above entities
BY: /s/ Xxxxx X. Xxxxxxxx
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Xxxxx X. Xxxxxxxx
Attorney-in-Fact
(Executed pursuant to Powers of Attorney)