31 U.S.C. § 3129 — Appropriation to pay expenses

(a) Amounts for necessary expenses, including rent, of an issue of obligations authorized under this chapter are appropriated to the Secretary of the Treasury. The appropriation may not exceed:

(1) 0.2 percent of the bonds and notes authorized under this chapter;

(2) 0.1 percent of the certificates of indebtedness authorized under section 3104 of this title; or

(3) 0.1 percent of the certificates of indebtedness authorized under the First Liberty Bond Act.

(b) The appropriation may be obligated only through the end of the fiscal year after the fiscal year in which the issue was made. If a specific amount is appropriated for expenses that this section funds without specifying an amount, only the specific appropriation may be obligated.