of this subsection shall be treated as the rate of salary or basic pay. (7) Nothing in this subsection shall be considered to permit or require the payment to any employee covered by this subsection at a rate in excess of the rate that would be payable were this subsection not in effect. (8) The Office of Personnel Management may provide for exceptions to the limitations imposed by this subsection if the Office determines that such exceptions are necessary to ensure the recruitment or retention of qualified employees. (b) Notwithstanding subsection (a), the adjustment in rates of basic pay for the statutory pay systems that take place in fiscal year 2018 under sections 5344 and 5348 of title 5, United States Code, shall be— (1) not less than the percentage received by employees in the same location whose rates of basic pay are adjusted pursuant to the statutory pay systems under sections 5303 and 5304 of title 5, United States Code: Provided , That prevailing rate employees at locations where there are no employees whose pay is increased pursuant to sections 5303 and 5304 of title 5, United States Code, and prevailing rate employees described in section 5343(a)(5) of title 5, United States Code, shall be considered to be located in the pay locality designated as Rest of United States pursuant to section 5304 of title 5, United States Code, for purposes of this subsection