Moneys in the Contract Payment Fund over and above those being accumulated for the next contract payment, and moneys in any other fund, except the Receiving Fund and the Operation and Maintenance Fund, may be invested in obligations of the United States. If such investments are made, the securities representing the same shall be kept on deposit with the bank having on deposit the funds from which such purchase was made. Income received from such investments shall be credited to the fund from which such investments were made.
(1974 Code Sec. 2.117)