An annuitant shall first be entitled to an initial increase under this Section on the January 1 next following the first anniversary of retirement, or January 1 of the year next following attainment of age 61, whichever is later. At such time, the system shall pay an initial increase determined as follows:
However, the initial annual increase calculated under this Section for the recipient of a disability retirement annuity granted under Section 16-149.2 shall be reduced by an amount equal to the total of all increases in that annuity received under Section 16-149.5 (but not exceeding 100% of the amount of the initial increase otherwise provided under this Section).
Following the initial increase, automatic annual increases in annuity shall be payable on each January 1 thereafter during the lifetime of the annuitant, determined as a percentage of the originally granted retirement annuity or disability retirement annuity for increases granted prior to January 1, 1990, and calculated as a percentage of the total amount of annuity, including previous increases under this Section, for increases granted on or after January 1, 1990, as follows: 1.5% for periods prior to January 1, 1972, 2% for periods after December 31, 1971 and prior to January 1, 1978, and 3% for periods after December 31, 1977.
Beginning January 1, 2016, the $1,000 referred to in item (2) of this subsection (a-1) shall be increased on each January 1 by the annual unadjusted percentage increase (but not less than zero) in the consumer price index-u for the 12 months ending with the preceding September; these adjustments shall be cumulative and compounded. For the purposes of this subsection (a-1), "consumer price index-u" means the index published by the Bureau of Labor Statistics of the United States Department of Labor that measures the average change in prices of goods and services purchased by all urban consumers, United States city average, all items, 1982-84 = 100. The new dollar amount resulting from each annual adjustment shall be determined by the Public Pension Division of the Department of Insurance and made available to the System by November 1 of each year.
This subsection (a-1) is applicable without regard to whether the person is in service on or after the effective date of this amendatory Act of the 98th General Assembly.
For the purposes of Section 1-103.1, this subsection (a-2) is applicable without regard to whether the person is in service on or after the effective date of this amendatory Act of the 98th General Assembly.
On January 1, 1987, any annuitant whose retirement annuity began on or before January 1, 1977, shall receive an increase in the monthly retirement annuity equal to 8 per year of creditable service times the number of years that have elapsed since the annuity began.
40 ILCS 5/16-133.1