Military branches: National Defense Secretariat (includes Army and Air Force), Navy Secretariat (includes Naval Air and Naval Infantry)
Military manpower - military age: 18 years of age
note: starting in 2000, females will be allowed to volunteer for military service
Military manpower - availability: males age 15-49: 26,703,300 (2001 est.)
Military manpower - fit for military service: males age 15-49: 19,394,184 (2001 est.)
Military manpower - reaching military age annually: males: 1,077,536 (2001 est.)