Bolivia
total: 21.47 years
male: 20.79 years
female: 22.17 years (2005 est.)
Bosnia and Herzegovina
total: 36.21 years
male: 35.81 years
female: 36.63 years (2005 est.)
Botswana
total: 19.29 years
male: 18.64 years
female: 19.93 years (2005 est.)
Brazil
total: 27.81 years
male: 27.06 years
female: 28.57 years (2005 est.)
British Virgin Islands
total: 30.9 years
male: 31.1 years
female: 30.7 years (2005 est.)
Brunei
total: 27.04 years
male: 27.63 years
female: 26.4 years (2005 est.)
Bulgaria
total: 40.66 years
male: 38.59 years
female: 42.66 years (2005 est.)
Burkina Faso
total: 16.82 years
male: 16.43 years
female: 17.22 years (2005 est.)
Burma
total: 26.14 years
male: 25.57 years
female: 26.72 years (2005 est.)
Burundi
total: 16.6 years
male: 16.27 years
female: 16.95 years (2005 est.)