10 U.S.C. § 12005

(a) (1) Subject to paragraph (2), the authorized strength of the Army and the Air Force in reserve commissioned officers in an active status in each grade named in paragraph (2) is as prescribed by the Secretary of the Army or the Secretary of the Air Force, respectively. A vacancy in any grade may be filled by an authorized appointment in any lower grade. (2) A strength prescribed by the Secretary concerned under paragraph (1) for a grade may not be higher than the percentage of the strength authorized for the Army or the Air Force, as the case may be, under section 12003 of this title that is specified for that grade as follows: Grade Army percentage Air Force percentage Colonel 2 1.8 Lieutenant colonel 6 4.6 Major 13 14.0 Captain 35 32.0 First lieutenant and second lieutenant (when combined with the number authorized for general officer grades under section 12004 of this title ) 44 47.6 (3) Medical officers and dental officers shall not be counted for the purposes of this subsection. (b) (1) The authorized strengths of the Navy Reserve in line officers in an active status in the grades of captain, commander, lieutenant commander, and lieutenant, and in the grades of lieutenant (junior grade) and ensign combined, are the following percentages of the total authorized number of those officers: Captain 1.5 percent Commander 7 percent Lieutenant commander 22 percent Lieutenant 37 percent Lieutenant (junior grade) and ensign (when combined with the number authorized for flag officer grades under section 12004 of this title ) 32.5 percent. (2) When the actual number of line officers in an active status in any grade is less than the number authorized by paragraph (1) for that grade, the difference may be applied to increase the number authorized by that paragraph for any lower grade or grades. (c) (1) The authorized strengths of the Marine Corps Reserve in officers in an active status in the grades of colonel, lieutenant colonel, major, and captain, and in the grades of first lieutenant and second lieutenant combined, are the following percentages of the total authorized number of those officers: Colonel 2 percent Lieutenant colonel 8 percent Major 16 percent Captain 39 percent First lieutenant and second lieutenant (when combined with the number authorized for general officer grades under section 12004 of this title ) 35 percent. (2) When the actual number of officers in an active status in any grade is less than the number authorized by paragraph (1) for that grade, the difference may be applied to increase the number authorized by that paragraph for any lower grade or grades. (d) (1) An officer of the Army or Air Force may not be reduced in grade because of a reduction in the number of commissioned officers authorized for the officer’s grade under this section. (2) An officer of the Navy Reserve or the Marine Corps Reserve may not be reduced in permanent grade because of a reduction in the number authorized by this section for his grade.