Benefits.

The relevant provisions of ss. 122.01-122.12, 122.15, 122.16, 122.18 to 122.20, inclusive, fixing or relating to eligibility for retirement, retirement compensation, and other benefits payable to members or for the account of members of this system in relation to members in division A hereof, shall apply with equal force and effect to members of division B, with the following exceptions:

(1) For the period of service of the member prior to the effective date of his or her social security coverage hereunder, retirement benefits shall be computed on average final compensation at the rate of 2 percent for each year of service rendered prior to such effective date and as provided in s. 122.08. For the period of membership in division B the member’s retirement compensation shall be computed on average final compensation at the rate of 1.5 percent for each year of service rendered after the effective date of said social security coverage.

(2) Members of division B retiring under the disability provisions of this chapter shall receive not less than 20 percent of their average final compensation.

(3) For those persons who become members of the retirement system on or after July 1, 1963, the amount of such retirement compensation shall not exceed that amount which when added to the member’s estimated annual primary insurance amount under social security coverage equals 80 percent of his or her average final compensation. The estimated annual primary insurance amount of the member shall be determined by the administrator on the basis of the social security coverage in effect on the member’s retirement date, assuming that payment of such primary insurance amount shall commence at the later of the member’s 65th birthday or actual age of retirement, and that the member earned his or her average final compensation in each year between the date of retirement and his or her 65th birthday for those members retiring prior to age 65.