You must perform at least 600 hours of service in a qualifying position A qualifying position is one in which an employee will perform 600 or more hours of service in a calendar year in one or more jobs with one or more participating public employers. each calendar year Twelve calendar months commencing on January 1 and ending on December 31. to earn creditable service Any period of time in which a participating public employer pays an active member a salary and the active member or the employer on the member's behalf pays contributions to PERS. For purposes of computing years of creditable service, full months and major fractions of a month are considered to be one-twelfth of a year and are added to all full years. One month of creditable service is earned for each major fraction of a month served. Creditable service includes all retirement credit received by a member. for that year.