For purposes of sections 23-2333 and 23-2334, the definitions found in section 23-2301 shall apply.
As of the date of adoption of the retirement system, a prior service annuity shall be computed for all employees who have been employees continuously for one year prior to the date of the adoption of the retirement system and who are at least twenty-five years of age. Such prior service annuity shall be equal to the number of years of creditable prior service multiplied by the prior service annuity factor.
The number of years of creditable prior service shall be the number of completed years of prior service less all years during which the employee was participating in or for which he or she received a benefit from a public retirement plan, but not more than twenty-five.
The prior service annuity factor shall be the smaller of (1) one dollar or (2) the employee's compensation for the last completed twelve months of prior service divided by two thousand four hundred.