Section 40 ILCS 5/7-209 - Earnings and Interest(a) Balances at the beginning of each year which remain in employee reserves at the end of the year shall be credited with interest annually at the prescribed rate.(b) Municipality reserves shall be charged or credited, as the case may be, with interest at the prescribed rate applied to the balance therein at the beginning of the year.(c) Municipality accounts receivable shall be charged with interest at a rate of 1/2% per month before July 1, 1984, and 1% per month thereafter on the balance therein unpaid one month or more. The unpaid balance shall include charges established retroactively because of failure of the municipality to report amounts which should be receivable. Credit balances shall be disregarded in this calculation.(d) The annuity total and permanent disability reserves shall be credited with interest at the prescribed rate at the end of each year. For purposes of this computation, the prescribed rate shall be applied to the balances therein at the beginning of the year.(e) Amounts credited or charged under subsection (a), (b), (c), or (d) of this Section shall be charged or credited to the earnings and experience variation reserve. Any remaining balance, in excess of the contingency balance established, shall be transferred to the municipality reserves in proportion to present values of the annuities of the annuitants of each participating municipality and participating instrumentality plus the balance in their municipality reserve.(f) The Board shall fix the rate of interest, to be charged on back, retroactive, or reinstatement contributions.P.A. 89-136, eff. 7/14/1995.