Sec. 8. (a) The board shall set the surcharge rates under IC 5-10.2-12-3 at a level to actuarially prefund:
(1) annual indexed thirteenth checks for all current retired members and beneficiaries retired before July 1, 2029; and
(2) one percent (1%) annual cost of living adjustments to future in-payment members and beneficiaries retired on or after July 1, 2029.
(b) The board shall not reduce the surcharge rates under IC 5-10.2-12-3 from the prior year.
(c) The board may increase the surcharge rates under IC 5-10.2-12-3 by not more than one-tenth percent (0.1%) of payroll from the prior year.
(d) This section expires December 31, 2031.