Military service age and obligation:

18 years of age (17 years of age with parental consent) for male and female voluntary service; maximum enlistment age 42 (Army), 27 (Air Force), 34 (Navy), 28 (Marines); service obligation 8 years, including 2-5 years active duty (Army), 2 years active (Navy), 4 years active (Air Force, Marines) (2008)

Manpower available for military service:

males age 16-49: 72,715,332 females age 16-49: 71,638,785 (2008 est.)

Manpower fit for military service:

males age 16-49: 59,413,358 females age 16-49: 59,187,183 (2008 est.)

Manpower reaching militarily significant age annually:

male: 2,186,440 female: 2,079,688 (2008 est.)

Military expenditures:

4.06% of GDP (2005 est.)