Contingency Reserve Account; Investment of Additional Funds. There shall be a contingency reserve account within the Retirement Fund for the purpose of payment of insurance benefits. Funds in the Retirement Fund in excess of the amount required for maintenance of the contingency reserve account may be invested by the Secretary of the Treasury of the United States but only in such manner as he may invest the Federal Old-Age and Survivors Insurance Trust Fund and the Federal Disability Insurance Trust Fund pursuant to Section 201(d) and (e) of the Social Security Act of the United States [42 U.S.C. § 401(d) and (e)]. Source: DL 5-12, § 1.