(a) Any member who has completed twenty-five years of state service and has reached the age of fifty prior to June 30, 1980, may elect to be retired on the first day of the month following such application and receive retirement benefits in accordance with the provisions of subdivision (3) of subsection (c) of section 5-162 , provided such member so elects prior to June 30, 1980.
(b) Any member who has completed at least ten but less than twenty-five years of state service and reached the age of fifty-five prior to June 30, 1980, may elect to be retired on the first day of the month following his application and receive retirement benefits in accordance with subsection (d) of this section, provided such member so elects prior to June 30, 1980.
(c) Any member who has completed at least five but less than ten years of state service and has reached the age of sixty-five prior to June 30, 1980, may elect to be retired on the first day of the month following such application and receive retirement benefits in accordance with the provisions of subsection (d) of this section, provided such member so elects prior to June 30, 1980.
(d) Each member referred to in subsections (b) and (c) of this section shall receive a monthly retirement income beginning on his retirement date equal to one-twelfth of (A) plus (B): (A) The number of years of state service taken to completed months, multiplied by the applicable percentage of his Social Security earnings determined from the table below for the appropriate age and years of state service; (B) the number of years multiplied by the applicable percentage of his excess earnings determined from the table below for such age and years of service.