(a) There is hereby created a cost-of-living increase, not to exceed 15 percent in any case, which shall be applied to the benefit of any retired teacher or any teacher who retires after October 1, 1975, whose retirement benefit, when calculated upon the 2.0125 percent factor, does not result in a benefit increase of 15 percent as compared to the benefit to which such retired member was entitled to receive prior to the implementation of the 2.0125 percent formula factor provided for in Section 16-25-14 and this section.

(b) Any person described in subsection (a) of this section shall be entitled to receive an amount which, when added to the benefit he is entitled to receive after the implementation of the 2.0125 percent formula factor, shall be sufficient to equal an increase of 15 percent above the benefit which such person was entitled to receive prior to the implementation of the 2.0125 percent formula factor provided for in Section 16-25-14 and this section.

(c) Anything in this section to the contrary notwithstanding, if, as of October 1, 1975, the minimum guaranteed annual pension payable to any person who became a member of the Teachers' Retirement System of Alabama prior to October 1, 1971, shall not be less than an amount which when added to his annuity is equal to $120.00 multiplied by the number of years of the member's creditable service not in excess of 25 years, in the case of service retirements, and $90.00 multiplied by the number of years of his creditable service not in excess of 25 years, in the case of disability retirements, then such minimum guaranteed annual pension shall be deemed to be the benefit such member was entitled to receive prior to the implementation of the 2.0125 percent formula factor provided for in Section 16-25-14 and this section.