40 ILCS 5/11-204
Amounts transferred from the city contribution reserve and the employees' contribution reserve for annuities which have been fixed, amounts deducted from an employee's salary after the age and service annuity has been fixed, and amounts transferred to this reserve from the investment and interest reserve, shall be credited to this reserve.
Age and service annuities and widow's annuities shall be charged to this reserve. Amounts refunded in accordance with Sections 11-148, 11-166, 11-172 and 11-149(2) of this Article shall be charged to this reserve.
When an employee whose annuity was fixed or granted, re-enters service before age 65, an amount determined under the provisions governing re-entry into service shall be charged to this reserve and transferred to the city contribution reserve and the salary deduction reserve, respectively, for age and service annuity. Such amount shall be divided in said reserves in the same proportion as that in which the previous transfer from such reserves to this reserve was made.
If the wife of the employee, when he re-enters service, is the same as that when the widow's annuity was fixed, an amount to be determined under the provisions governing re-entry into service shall be transferred from this reserve and credited for widow's annuity in the city contribution reserve and the employees' contribution reserve, respectively. Such credit shall be in the same proportion as that in which the previous transfer was made.
If at the end of any year the credit balance of the annuity payment reserve exceeds the liabilities chargeable thereto by more than 15% of such liabilities, the excess shall be transferred to the investment and interest reserve, expense reserve, ordinary disabling reserve, prior service annuity reserve, and city contribution reserve, in the order named, to remove any deficiency existing in any such reserves.
40 ILCS 5/11-204