Sec. 38. (a) The pension portion (plus postretirement increases to the pension portion) provided by employer contributions of the monthly benefit payable after December 31, 2005, to a member of the public employees' retirement fund (or to a survivor or beneficiary of a member of the public employees' retirement fund) who retired or was disabled:
(1) before July 2, 1990, shall be increased by two percent (2%); and
(2) after July 1, 1990, and before January 1, 2005, shall be increased by one and one-half percent (1.5%).
(b) The increases specified in this section:
(1) are based on the date of the member's latest retirement or disability;
(2) do not apply to benefits payable in a lump sum; and
(3) are in addition to any other increase provided by law.