; and (2) voluntary early retirement payments (sections 8336(d)(2)(D) and 8414(b)(1)(B) of such title). (c) Involuntary reductions (1) In general Beginning on October 1, 2018, if voluntary reductions are inadequate to achieve the limitations provided in subsection (a), the Secretary of Defense shall separate employees using involuntary measures, including reductions in force. (2) RIF application Notwithstanding any other provision of law, rule, or regulation, when applying retention factors with respect to any employee during any reduction in force under paragraph (1), the Secretary of Defense shall assign greater weight to the performance factor over the other factors if such employee has a summary rating level of fully successful or better. (d) Adjustment of limit (1) Determination As soon as practicable after the start of each of fiscal years 2024 through 2028, the Secretary of Defense shall determine the difference (if any), expressed as a percentage, between the permanent active duty end strength minimum levels in effect under section 691(b) of title 10, United States Code, for the current fiscal year and the preceding fiscal year. (2) Adjustment On the date that the determination is made under paragraph (1), the Secretary shall adjust the limitations provided under subsection (a) with respect to the number of total full-time equivalent positions and Senior Executive Service positions by a percentage equal to the percentage determined under paragraph (1). (3) Achievement of adjustment After any adjustment under paragraph (2), in order to achieve the adjusted limitation for the applicable fiscal year, the Secretary (as the case may be)— (A) may hire individuals to occupy full-time equivalent positions