Any funds of the retirement system available for investment shall be invested by the Nebraska Investment Council pursuant to the Nebraska Capital Expansion Act and the Nebraska State Funds Investment Act. Payment for investment services by the council shall be charged directly against the gross investment returns of the funds. Charges so incurred shall not be a part of the retirement board’s annual budget request. The amounts of payment for such services, as of December 31 of each year, shall be reported not later than March 31 of the following year to the council, the retirement board, and the Nebraska Retirement Systems Committee of the Legislature. The report submitted to the committee shall be submitted electronically. All money received by the State Treasurer and the retirement board for the retirement system shall be invested by the state investment officer within thirty-one days after receipt.