Section 40 ILCS 5/13-401 - Term of service(a) In computing the term of service, the following periods of time shall be counted as periods of service for annuity purposes only: (1) the time during which the employee performs services required by the Employer. (2) approved vacations or leaves of absence with whole or part pay. (3) any period for which the employee receives a disability benefit payable under this Article. (4) leaves of absence for military service as provided in Section 13-403(a), and military service as provided in Section 13-403(b). (b) In computing the term of service for the ordinary disability benefit, the following periods of time shall be counted as periods of service: (1) the time during which the employee performs services required by the Employer. (2) approved vacations or leaves of absence with whole or part pay. (3) any period for which the employee receives a duty disability benefit under this Article. (c) Any employee who first enters service before the effective date of this amendatory Act of 1997 may, during any period of approved leave of absence without pay, continue to make contributions for the retirement and surviving spouse's annuities for a total period not to exceed one year during the employee's entire aggregate service with the Employer. Upon making these contributions, the employee shall receive credit in terms of length of service for the retirement and surviving spouse's annuities. Concurrent Employer's contributions shall be provided by the District. (d) An employee may establish credit for periods of approved leave of absence without pay, not to exceed a total of one year during the employee's aggregate service with the employer. To establish this credit, the employee must either continue to remain on approved leave of absence, return to service with the employer, or in the case of an employee who first enters service on or after the effective date of this amendatory Act of 1997, return to service with the employer for at least one calendar year. The employee must pay to the Fund the corresponding employee contributions, plus interest at the annual rate from time to time determined by the Board, compounded annually from the date of service to the date of payment. The corresponding employer contributions shall be provided by the District. Upon making the required contributions, the employee shall receive credit in terms of length of service for the retirement and surviving spouse's annuity in proportion to the number of pay periods or portion thereof for which contributions were made relative to 26 pay periods. (e) Overtime or extra service shall not be included in computing any service. Not more than one year of service credit shall be allowed for service rendered during any calendar year.Amended by P.A. 093-0334, § 5, eff. 7/24/2003. P.A. 90-12, eff. 6-13-97.