The retirement allowance of a member shall be based on the membership service rendered or established by him since he last became a member and, if he has a prior service certificate in full force and effect, the amount of the prior service so certified. (Ga. L. 1943, p. 640, § 4.)
Service which is creditable toward a retirement allowance
O.C.G.A. § 47-3-100, under RETIREMENT AND ELIGIBILITY FOR RETIREMENT ALLOWANCES.
O.C.G.A. § 47-3-100