(a) At the end of each fiscal year, the Board of Trustees of the Arkansas Public Employees' Retirement System may allow the crediting of interest at an amount to be determined on the balance at the beginning of the fiscal year in the members' deposit account and the employers' accumulation account.
(b) The board shall be required to allow regular interest at the end of each fiscal year on the year's mean balance in the retirement reserve account.
(c) The interest allowed under subsections (a) and (b) of this section shall be credited annually by the board to the accounts and shall be paid from the income account.