Military branches:
Army; Navy (includes naval air arm); Air Force; Coast Guard (2011)
Military service age and obligation:
16-18 years of age for voluntary military service (Army 17 1/2, Air Force 17, Navy 16 1/2); no conscription; women may join as officers, but for noncombat roles only (2012)
Manpower available for military service:
males age 16-49:
319,129,420
females age 16-49:
296,071,637 (2010 est.)
Manpower fit for military service:
males age 16-49:
249,531,562
females age 16-49:
240,039,958 (2010 est.)
Manpower reaching militarily significant age annually:
male:
12,151,065
female:
10,745,891 (2010 est.)
Military expenditures:
2.43% of GDP (2012)
country comparison to the world: 31
2.58% of GDP (2011)
2.43% of GDP (2010)
[see also: Military expenditures country ranks ]