31 U.S.C. § 9702

Investment of trust funds

Except as required by a treaty of the United States, amounts held in trust by the United States Government (including annual interest earned on the amounts)—

(1)

shall be invested in Government obligations; and

(2)

shall earn interest at an annual rate of at least 5 percent.

( Pub. L. 97–258 , Sept. 13, 1982 , 96 Stat. 1052 .)