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14 U.S. Code § 2111 - Promotion zones

(a) Before convening a selection board to recommend officers for promotion to any grade above lieutenant (junior grade) and below rear admiral (lower half), the Secretary shall establish a promotion zone for the grade to be considered. The promotion zone for each grade shall consist of the most senior officers of that grade on the active duty promotion list who are eligible for consideration for promotion to the next higher grade and who have not previously been placed in a promotion zone for selection for promotion to the next higher grade. The number of officers in each zone shall be determined after considering—
the needs of the service;
the estimated numbers of vacancies available in future years to provide comparable opportunity for promotion of officers in successive year groups; and
the extent to which current terms of service in that grade conform to a desirable career promotion pattern.
However, such number of officers shall not exceed the number to be selected for promotion divided by one-half.
Promotion zones from which officers will be selected for promotion to the grade of rear admiral (lower half) shall be established by the Secretary as the needs of the service require.
(Added Pub. L. 88–130, § 1(10)(C), Sept. 24, 1963, 77 Stat. 179, § 256; amended Pub. L. 89–444, § 1(16), June 9, 1966, 80 Stat. 196; Pub. L. 97–417, § 2(3), Jan. 4, 1983, 96 Stat. 2085; Pub. L. 99–145, title V, § 514(c)(1), Nov. 8, 1985, 99 Stat. 629; Pub. L. 99–661, div. A, title XIII, § 1343(c), Nov. 14, 1986, 100 Stat. 3995; renumbered § 2111 and amended Pub. L. 115–282, title I, § 112(b), title III, § 312, Dec. 4, 2018, 132 Stat. 4216, 4249.)
Editorial Notes

2018—Pub. L. 115–282, § 112(b), renumbered section 256 of this title as this section.

Subsec. (a). Pub. L. 115–282, § 312, substituted “one-half.” for “six-tenths.” in concluding provisions.

1986—Subsec. (b). Pub. L. 99–661 substituted “rear admiral (lower half)” for “commodore”.

1985—Subsec. (a). Pub. L. 99–145 substituted “rear admiral (lower half)” for “commodore”.

1983—Subsecs. (a), (b). Pub. L. 97–417 substituted “commodore” for “rear admiral”.

1966—Subsec. (a). Pub. L. 89–444 limited promotion zone by requiring that list of officers under consideration be officers eligible for consideration for promotion to next higher grade.