EXHIBIT I JOINT FILING AGREEMENT ---------------------- 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 13, 2009 AXA Financial, Inc. BY: /s/ Alvin H. Fenichel ----------------------------------------- Alvin H. Fenichel Senior Vice President and Controller AXA Assurances I.A.R.D. Mutuelle; AXA Assurances Vie Mutuelle; as a group, and AXA Signed on behalf of each of the above entities BY: /s/ Alvin H. Fenichel ----------------------------------------- Alvin H. Fenichel Attorney-in-Fact (Executed pursuant to Powers of Attorney)