Sec. 11. 1982 Postretirement Increases. (a) The monthly benefit payable after June 30, 1982, to a member, or a survivor or beneficiary of a member, who retired or was disabled before July 2, 1980, shall be increased by four percent (4%).
(b) The increase specified in this section:
(1) shall be based upon the date of the member's initial retirement or disability;
(2) does not apply to benefits payable in a lump sum; and
(3) is in addition to any other increase provided by law.