This report contains history, current law and funding levels for Illinois pension funds. A good reference document.
For instance page 82 of pdf has details for TRS, Tier 1 (hired prior to 1/1/2011)
- Basic Rate of Annuity: 2.2% per year of service
- Maximum Annuity: 75%
It would take just over 34 years to reach the max of 75%
Not listed here, unused sick and vacation days count towards service. Two years is not unusual.
If a teacher started right out of college at age 22, worked 33 years and cashed in 2 years of accrued sick/vacation days, that would allow him to retire at age 55 with FULL (75% of the average last 4 years of salary) benefits.
This report has data for each state run fund, each Chicago fund, and fire & police retirement funds for each municipality.