Illinois Statutes Chapter 40. Pensions § 5/20-106. Final average salary

(a) “Final average salary”: The average (or other) salary which is considered by a participating system in determining the amount of the retirement annuity or survivor's annuity.

(b) Earnings credits under all participating systems shall be considered by each system in determining final average salary, but subject to the limitations imposed by this amendatory Act of the 98th General Assembly for a participant in a defined contribution plan established under Article 2, 14, 15, or 16 of this Code. In calculating a proportional retirement or survivor's annuity based on these earnings credits, the participating system shall apply any limitations on earnings for annuity purposes that are imposed by the Article governing the system.