Section 27-210-64-105 - Calculation of the cost of purchasing eligible service1. The member shall pay to PERS on the date he or she is eligible for credit for such service or at any time thereafter prior to the date of retirement the actuarial cost as determined by the actuary for each year of creditable service.2. The cost is a "point in time" determination using an actuarial calculation based on the member's service credit before the purchase, the member's service after the purchase, the member's age, and the greater of the member's current annual salary or the average of the highest four years of compensation. a. Computation of cost for active members i. An active member is an individual who is currently employed in covered employment.ii. PERS will determine the member's average compensation and current annual salary based on his or her membership account.iii. Using the actuarial factors for active members as provided by the actuary, PERS will determine the actuarial factor based on the member's current age and years of service and the actuarial factor based on the member's current age and years of service including the service eligible for purchase.iv. The difference between the two actuarial factors will be multiplied by the higher of the active member's average compensation or current annual salary as determined by PERS. The result is the total cost for the service.b. Computation of cost for inactive membersi. An inactive member is an individual who is no longer employed in covered employment and who has not retired or received a refund of his or her contributions.ii. PERS will determine the member's average compensation from his or her membership account.iii. Using the actuarial factors for inactive members as provided by the actuary, PERS will determine the actuarial factor based on the member's current age and years of service and the actuarial factor based on the member's current age and years of service including the service eligible for purchase.iv. The difference between the two actuarial factors will be multiplied by the inactive member's average compensation. The result is the total cost for the service.3. The cost schedule will reflect the total cost of all eligible service, as well as the cost of the individual increments of service credit. The member may purchase all or any part of the service prior to his or her effective retirement date with PERS. All purchases must be in not less than monthly increments.4. If a member does not purchase the service before the date stated on the cost schedule, the cost of any remaining eligible service not purchased by the stated date will be recalculated. The cost will change as the member's age and service credited to the member's account change.27 Miss. Code. R. 210-64-105