prior to the time of purchase. For the first seven (7) years commencing January 1, 2013, this rate shall be computed upon the City’s average annual percentage of payroll contributions to Tier 2, with the rate for any missing year(s) based upon the average of the annual rate(s) for the prior year(s). (f) Method of Purchase. (1) The member may elect to pay on an after-tax basis in a lump sum or in biweekly installments through payroll deduction, subject to any applicable Internal Revenue Code restrictions. (2) The Board may establish rules to allow members to pay for purchases via rollovers of funds. (3) Should the member elect to purchase the buy back service credit through payroll deduction, annual interest at a rate determined by the Board and set at the commencement of the agreement shall be charged. The Board may establish a minimum biweekly payroll deduction. (g) Execution of the Agreement. A member entering into a buy back agreement shall complete all contributions prior to the effective date of retirement in order to receive agreed upon buy back credit. In the event the member elects to retire prior to completion of the buy back agreement, the member may receive prorated buy back credit for that portion of the service with other governmental entities or uncompensated maternity leave which have been purchased by contributions already made and forfeit the remainder of credit covered by the agreement; or the member may make a lump sum payment sufficient to complete the total payment covered by the agreement. Additionally, a member who elects to terminate an after-tax agreement prior to its completion, or at the time of retirement, may elect to receive a cash refund of the buy back contributions and interest payable upon the earlier of death, termination of employment or retirement or prorated buy back credit. (h) Member’s Death. In the event that a member who has entered into a buy back agreement dies prior to retirement, the funds paid for this purchase shall be considered to be a part of the member’s accumulated contributions and shall be refunded accordingly, with interest thereon computed at the rate applicable to regular member contributions. (i) Member’s Disability Retirement.