(a) Upon service retirement, a member shall receive a service retirement allowance which shall consist of:

(1) An annuity which shall be the actuarial equivalent of his accumulated contributions at the time of his retirement;

(2) A pension equal to the annuity allowable at age of retirement, but not to exceed an annuity which would have been allowed at age 65, which pension shall be computed on the basis of his contributions made prior to attaining age 65, provided that any member may continue his contributions after attaining 65 years of age, and by so doing shall receive membership service credit for such period of time, which shall be used in the computation of retirement allowances; and

(3) If he has a prior service certificate in full force and effect, an additional pension which shall be equal to the annuity allowable at age of retirement, provided that such pension does not exceed the annuity which would have been allowable at age 65 by more than twice the amount of his prior service accumulations as defined in Code Section 47-2-96 with regular interest on such amount as from time to time in effect, which interest shall be figured from the date of establishment until the earlier of the date of his retirement or the date on which he attains 65 years of age.

(b) No person who at any time elected nonmembership shall establish, nor shall any person who transferred to the retirement system or who previously became a member shall increase, the pension set forth in paragraph (3) of subsection (a) of this Code section by reason of his employment in or transfer to another employer. No member shall be eligible for that pension unless at least 30 days of his prior service was earned within an 18 month period immediately preceding his date of membership.

(c) Anything in this chapter to the contrary notwithstanding, any member with 30 years of service, regardless of age, shall be eligible to retire forthwith and, upon retirement, shall be paid not less than the service retirement allowance which would have been payable to such member upon service retirement at age 65 with 30 years of service.

(d) Anything in this chapter to the contrary notwithstanding, any member with at least 34 years of service shall be eligible to retire forthwith and upon retirement shall be paid not less than the service retirement allowance which would have been payable upon service retirement at the age of 65 had he continued in service without further change in compensation.

(e) In the case of any member who has at least 25 but less than 30 years of creditable service and who has not reached the age of 60 years upon retirement, the service allowance set forth in subsection (a) of this Code section shall be reduced by an actuarial equivalent certified by the board of trustees. Such reduced amount shall take into consideration the member's age and number of years of creditable service at the time of retirement and shall be sufficient to permit retirement at such age or with such number of years of creditable service without creating any accrued liability against the retirement system. Such reduction shall not apply in calculating the service allowance for disability retirement or death. Any member who retires with less than 30 years of creditable service or who has not obtained the age of 60 at the time of retirement shall not become eligible for postretirement benefit adjustments until such time as the member reaches the age of 60 or would have obtained 30 years of creditable service, whichever occurs earlier.