AGREEMENT OF FILING OF SCHEDULE 13GWarburg Pincus LLC • June 8th, 2009 • Natural gas transmission
Company FiledJune 8th, 2009 IndustryThe undersigned acknowledge and agree that the foregoing statement on Schedule 13G is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on Schedule 13G shall be filed on behalf of each of the undersigned without the necessity of additional joint filing statements. The undersigned acknowledge that each shall be responsible for the timely fling of such amendments, and for the completeness and accuracy of the information concerning the others, except to the extent that it knows or has reason to believe that such information is inaccurate. This Agreement may be executed in any number of counterparts and all such counterparts taken together shall constitute one and the same instrument.