Klaus Weidenbach
Interesting what data you can find at the CIA.

Cia: The World Factbook - Costa Rica



Military branches:
no regular military forces; Ministry of Public Security, Government, and Police (2011)

Manpower available for military service:
males age 16-49: 1,255,798
females age 16-49: 1,230,202 (2010 est.)

Manpower fit for military service:
males age 16-49: 1,058,419
females age 16-49: 1,037,053 (2010 est.)

Manpower reaching militarily significant age annually:
male: 42,201
female: 40,444 (2010 est.)
#^