La. Consolidated Public Retirement § 11:3549
The board of trustees of the cities of Opelousas and Ruston may make annual supplemental monthly cost-of-living adjustments to all retirees and beneficiaries, from interest earnings or from the general fund of the municipal treasury, in an amount not to exceed three percent of the base retirement or survivors' benefit. In addition, the boards may provide an additional annual supplemental monthly cost-of-living adjustment to retirees and beneficiaries who are sixty-five years of age or over, which shall not exceed two percent of the base retirement or survivors' benefit. These adjustments shall be effective on July first of each year, commencing July 1, 1981, and shall be applicable to retirees and beneficiaries on record on July first of the immediately preceding calendar year.
La. Consolidated Public Retirement § 11:3549