(1) Any member who retires on or after such member’s normal retirement date shall be entitled to receive an annual retirement benefit equal to the sum obtained by adding an amount for participating service and an amount for prior service determined as provided in this section. The amount for prior service shall be equal to 1% of the member’s prior service annual salary multiplied by the number of years of prior service entitled to credit as provided in Kan. Stat. Ann. § 74-4913, and amendments thereto, except that for members retiring on or after July 1, 1981, who were last employed by a participating employer which had affiliated with the system under Kan. Stat. Ann. § 74-4910, 74-4912, 74-4929 or 74-4991, and amendments thereto, and for the period commencing January 1, 1986, for members retiring before July 1, 1981, who were last employed by a participating employer which had affiliated with the system under Kan. Stat. Ann. § 74-4910, 74-4912, 74-4929 or 74-4991, and amendments thereto, except that any increase in benefits under this section shall be reduced by any postretirement benefit adjustments received by such member prior to July 2, 1985, the amount for prior service shall be calculated using final average salary in lieu of prior service annual salary and, in the case of any such member who became a member under subsection (3) of Kan. Stat. Ann. § 74-4925, and amendments thereto, and for whom a final average salary cannot be otherwise determined, such member’s final average salary shall be based on all service for which such member received assistance in a plan under subsection (2) of Kan. Stat. Ann. § 74-4925, and amendments thereto, as certified by such employer upon request of the board. For any member who retires on or after July 1, 1993, the amount for participating service shall be equal to the total of 1.75% of the member’s final average salary multiplied by the number of years of participating service earned prior to January 1, 2014, and, subject to any election made pursuant to the provisions of Kan. Stat. Ann. § 74-49,135, and amendments thereto, 1.4% or 1.85% of the member’s final average salary multiplied by the number of years of participating service earned on and after January 1, 2014. If the federal internal revenue service fails to grant an approval or issues an adverse decision as described in Kan. Stat. Ann. § 74-49,135, and amendments thereto, the amount for participating service earned on and after January 1, 2014, shall be 1.85% of the member’s final average salary multiplied by the number of years of participating service earned on and after January 1, 2014. Notwithstanding any provision of law to the contrary, service that is purchased under the provisions of Kan. Stat. Ann. § 74-4919a et seq., and amendments thereto, shall be credited at a rate which equals 1.4% of the member’s final average salary for members that elect the 1.4% multiplier pursuant to subsection (b)(2) of Kan. Stat. Ann. § 74-49,135, and amendments thereto, and 1.75% of the member’s final average salary for members that elect the 1.85% multiplier pursuant to subsection (b)(1) of Kan. Stat. Ann. § 74-49,135, and amendments thereto.

(2) (A) Any member who retires on or after July 1, 1993, but before the normal retirement date and has attained age 60 but has not attained age 62 with the completion of 10 years of credited service, shall receive an annual retirement benefit equal to the annual retirement benefit payable had the member retired on the normal retirement date but based upon the member’s final average salary and years of participating and prior service credited to the date of actual retirement reduced by an amount equal to the product of (i) such annual retirement benefit payable had the member retired on the normal retirement date, multiplied by (ii) the product of .2% multiplied by the number of months’ difference, to the nearest whole month, between the member’s attained age at the time of retirement and age 62.

(B) Any member who retires on or after July 1, 1993, but before the normal retirement date and has attained age 55 but has not attained age 60 with the completion of 10 years of credited service, shall receive an annual retirement benefit equal to the annual retirement benefit payable had the member retired on the normal retirement date but based upon the member’s final average salary and years of participating and prior service credited to the date of actual retirement reduced by an amount equal to the total of: (i) (a) The product of such annual retirement benefit payable had the member retired on the normal retirement date, multiplied by (b) the product of .6% multiplied by the number of months’ difference, to the nearest whole month, between the member’s attained age at the time of retirement and age 60; and

(ii) on and after July 1, 1993, the product of such annual retirement benefit payable had the member retired on the normal retirement date, multiplied by 4.8%.

(3) Upon death of a retirant, there shall be paid to such retirant’s beneficiary an amount equal to the excess, if any, of such retirant’s accumulated contributions over the sum of all retirement benefit payments made.

(4) Such annual retirement benefits shall be paid in equal monthly installments, except that the board may provide for the payment of retirement benefits which total less than $240 a year on other than a monthly basis.

(5) In the event that an application in such form as may be prescribed by the board for any amount due under the provisions of this act, is not filed with the office of the retirement system by the person entitled to same within five years of the date such amount became due and payable, an amount equal to same shall be transferred to the retirement benefit accumulation reserve and such amount shall no longer be due and payable, except that if any such person shall present evidence satisfactory to the board that such person’s failure to file such application within that time period was due to lack of knowledge or incapacity on such person’s part, the amount equal to the amount originally due shall be transferred from the retirement benefit accumulation reserve to the reserve or reserves from which such transfer was initially made and the amount originally due shall be paid to such person.

(6) The participating employer, when an employee files an application for retirement, shall certify to the system all member contributions of such employee which have not been reported previously. In the event the amount certified results in an overpayment of retirement benefits, the employer shall be held responsible for the contribution amount previously certified from the time of commencement of the overpayment of retirement benefits until the time that such overpayment is discovered by the system. At the time that such overpayment of retirement benefits is discovered by the system, the system shall adjust the amount of retirement benefits paid to the employee to the correct amount based on the participating employer’s certification of member contributions which had not been previously reported. The participating employer of the employee who has had such member’s retirement benefits adjusted as provided in this subsection shall notify such employee of such overpayment and such adjustment of retirement benefits. If the contributions previously certified are lower than the actual amount reported, the employer shall be responsible for remitting the correct amount and the member’s monthly benefit shall be recalculated based on the amount reported by the employer. When an employee in school employment files such an application, the participating employer responsible for any such amounts as provided in this subsection shall be the employee’s eligible employer as specified in subsection (1), (2) or (3) of Kan. Stat. Ann. § 74-4931, and amendments thereto, and shall not be the state of Kansas. The provisions of law in effect on the retirement date of a member under the system shall govern the retirement benefit payable to the retirant, any joint annuitant and any beneficiary.