40 ILCS 5/6-198
The following amounts shall be credited to this reserve: (1) All contributions of the city for prior service annuity and widow's prior service annuity; (2) all other contributions of the city to provide prior service annuities in accordance with this Article shall be credited to this reserve; and (3) all assets of any firemen's pension fund which were received by the board under "An Act to provide for a firemen's pension fund and to create a board of trustees to administer said fund in cities having a population exceeding two hundred thousand (200,000) inhabitants", filed June 14, 1917, as amended, in such city on the effective date, as provided in Section 10-9-53 of the Firemen's Annuity and Benefit Fund Act of the Illinois Municipal Code.
All prior service annuities and widow's prior service annuities payable under this Article and the "Firemen's Annuity and Benefit Fund Act of the Illinois Municipal Code", and all annuities, benefits and pensions which have been or shall be granted under said Act, filed June 14, 1917, as amended, and the requirements for term annuities, shall be charged to this reserve.
If at any time the balance in the investment and interest reserve is not sufficient to permit a transfer from that reserve to the annuity payment reserve of such amounts as are necessary according to the American Experience Table of Mortality and the Combined Annuity Table and applicable rates of interest, whichever table applies, to make the balance of the annuity payment reserve equal to the liabilities chargeable thereto (including among such liabilities, and in addition to all other liabilities of such reserve, the present values of all annuities entered upon, and of all annuities fixed and not entered upon to be charged to such reserve) any amount necessary for such purpose shall be transferred from this reserve to the investment and interest reserve.
40 ILCS 5/6-198