§25–307.

    (a)    Creditable service on which the allowance of a member is based consists of:

        (1)    eligibility service, except as provided in subsection (b) of this section; and

        (2)    credit for unused sick leave as provided in § 20-206 of this article.

    (b)    A member’s creditable service for a period of regular part-time employment equals the member’s actual employment during that period.