(a) As used in this Code section, the term "beneficiary" shall have the meaning specified in paragraph (7) of Code Section 47-3-1 and shall also mean and include any retired public school teacher who retired pursuant to any county, municipal, or local board of education retirement or pension system.

(b) Subject to the limitations of subsection (c) of this Code section, effective July 1, 1988, the monthly retirement benefit of each beneficiary shall be increased by a percentage which varies in accordance with the time of retirement as follows:

Time_of_Retirement Percentage_Increase

Prior to July 1, 1964.......................................... 15.0

July 1, 1964, through June 30, 1969............................ 13.0

July 1, 1969, through June 30, 1970............................ 10.0

July 1, 1970, through June 30, 1971............................ 8.0

July 1, 1971, through June 30, 1972............................ 7.0

July 1, 1972, through June 30, 1973............................ 6.0

July 1, 1973, through June 30, 1974............................ 5.5

July 1, 1974, through June 30, 1975............................ 5.0

July 1, 1975, through June 30, 1976............................ 4.0

July 1, 1976, through June 30, 1977............................ 3.5

July 1, 1977, through June 30, 1978............................ 3.0

July 1, 1978, through June 30, 1979............................ 2.5

July 1, 1979, through June 30, 1980............................ 2.0

July 1, 1980, through June 30, 1981............................ 1.5

July 1, 1981, through June 30, 1982............................ 1.0

July 1, 1982, through June 30, 1983............................ 0.5

July 1, 1983, through June 30, 1984............................ 0.5

After June 30, 1984............................................ 0.0

(c) The full percentage increase provided for in subsection (b) of this Code section shall apply only to those beneficiaries who had 20 or more years of creditable service at the time of retirement. For those beneficiaries who had at least ten but less than 20 years of creditable service at the time of retirement, the monthly benefit increase provided for by subsection (b) of this Code section shall be reduced by 5 percent for each year less than 20 years of creditable service. Beneficiaries who had less than ten years of creditable service shall not receive an increase in their monthly retirement benefit under this Code section. No one person's retirement benefit or combination of retirement benefits shall exceed $1,500.00 per month as a result of an increase in the monthly retirement benefit under this Code section.