Louisiana Revised Statutes Tit. 11, § 3865. Computation of retirement allowance

(1) Those who have completed at least twenty years but less than thirty years of creditable service shall receive and be paid a monthly allowance equal to fifty percent of one-twelfth of the annual salary received by him during the twelve-month period immediately preceding the date of his retirement.

(2) Those who have completed thirty or more years of creditable service shall receive and be paid a monthly allowance equal to sixty-five percent of one-twelfth of the annual salary being received by him at the time of his application for retirement.