(a) Each employee retiring on or after July 1, 1975, and prior to the effective date of the next collective bargaining agreement following July 1, 1978, which applies to such employee and the spouse of any such deceased employee who had elected the husband and wife retirement income option, shall be eligible for an annual five per cent cost of living allowance commencing on the first anniversary date following the completion of nine months in retirement. If on any subsequent applicable anniversary date, the Retirement Commission determines that the National Consumer Price Index for urban wage earners and clerical workers for the previous twelve-month period has increased less than the cost of living allowance provided by this subsection, the cost of living allowance provided by this subsection shall be adjusted to reflect the change in such index provided such cost of living allowance shall not be less than three per cent.

(b) Each employee retiring on or after the effective date of the next collective bargaining agreement following July 1, 1978, which applies to such employee, and the spouse or contingent annuitant of any such deceased employee who had elected an optional form of retirement income, shall be eligible for an annual three per cent cost of living allowance commencing on the first anniversary date following the completion of nine months in retirement and any additional cost of living allowance which may be obtained under the terms of a collective bargaining agreement.

(c) Each employee who is not included in any collective bargaining unit and who retires after July 1, 1980, and the spouse or contingent annuitant of any such deceased employee who had elected an optional form of retirement income, shall be eligible for an annual three per cent cost of living allowance commencing on the first anniversary date following the completion of nine months in retirement. Cost of living allowances provided under subsections (a), (b), and (c) of this section shall be computed on the basis of the retirement allowance to which the employee was entitled on the day preceding his latest anniversary date. Anniversary date means the first day of January or the first day of July following completion of nine months after the effective date of retirement.

(d) Each spouse or contingent annuitant of a deceased member who is receiving income under § 5-165 or § 5-165a shall be eligible for an annual three per cent cost of living allowance unless the spouse or contingent annuitant is receiving a six per cent cost of living allowance as provided in § 5-162h.