Amends provisions regarding the surcharge rates established by the Indiana public retirement system to actuarially prefund certain postretirement benefits. Adds provisions requiring the treasurer of state to determine a surcharge amount that is to be paid into the supplemental reserve account for the state police pre-1987 and 1987 benefit systems. Provides for a thirteenth check in calendar year 2025 for certain members, participants, or beneficiaries of the: (1) Indiana state teachers' retirement fund; (2) Indiana public employees' retirement fund; (3) state excise police, gaming agent, gaming control officer, and conservation enforcement officers' retirement plan; (4) state police pre-1987 benefit system; and (5) state police 1987 benefit system. Makes conforming changes.