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22 U.S. Code § 284x - Sixteenth replenishment

(a)
The United States Governor of the International Development Association is authorized to contribute on behalf of the United States $4,075,500,000 to the sixteenth replenishment of the resources of the Association, subject to obtaining the necessary appropriations.
(b)
In order to pay for the United States contribution provided for in subsection (a), there are authorized to be appropriated, without fiscal year limitation, $4,075,500,000 for payment by the Secretary of the Treasury.