The Federal Service Labor Management Relations Statute gives federal employees the right to bargain collectively with government employer units over their 'conditions of employment.' Matters 'specifically provided for' by federal statute, however, are excepted from bargaining. That exception applies to the wages of 'prevailing rate' employees. The unions representing six bargaining units at D submitted a variety of negotiating proposals and announced that they sought to negotiate the 'method by which wage rates of their respective crafts are set, adjusted and maintained insofar as permitted by law.' P refused to bargain invoking both the 'management rights' exception of 5 U.S.C. § 7106(a)(1) and the exception for matters 'specifically provided for' by statute. The unions appealed to D, which found the unions' proposals negotiable. The statute governing the wages of D employees, 5 U.S.C. § 5349(a), uses a two-factor formula that looks to the 'prevailing rates' of similar private-sector employees and the demands of the 'public interest': The pay of employees … in various agencies, including P shall be fixed and adjusted from time to time as nearly as is consistent with the public interest in accordance with prevailing rates . . . as the pay-fixing authority of each such agency may determine. The Prevailing Rate Systems Act (PRSA) sets the pay-rate standard for most federal employees 5 U.S.C. § 5343. As between §5343 and §5349, §5343 describes the rate-setting process in greater detail. In recent cases, D held that wages under a related section of the Prevailing Rate Systems Act, 5 U.S.C. § 5343, met the terms of the 'specifically provided for' exception. For its decision, in this case, D had either to distinguish key cases or to reject them and explain the rejection. P appealed.