Officers and career employees hired prior to January 1, 1984, are covered by the CSRS, which provides a basic annuity toward which the Postal Service and the employee contribute at rates prescribed by law. Effective October 2006, P.L.109-435 suspends the employer obligation to make contributions for CSRS employees’ retirement until 2017. At that time, OPM will perform an actuarial valuation to determine whether additional payments are necessary. The Postal Service does not match TSP contributions for employees participating in CSRS.