After April 13, 1979, the contributions of the state under this Code section to this system shall be determined by the board each year on the basis of the most recent actuarial valuation. The board shall certify to the legislative fiscal officer the amount of the state's contributions due to the system. The state's contributions shall be paid from funds appropriated to the legislative branch of government and shall be in an amount determined by the board to be necessary to cover the costs of financing and administering the system. The legislative fiscal officer is directed to pay to the board the contributions of the state together with an amount necessary to cover the required employer contributions for social security coverage.