Bhutan
at birth: 1.05 male(s)/female
under 15 years: 1.04 male(s)/female
15-64 years: 1.14 male(s)/female
65 years and over: 1.13 male(s)/female
total population: 1.1 male(s)/female (2008 est.)

Bolivia
at birth: 1.05 male(s)/female
under 15 years: 1.04 male(s)/female
15-64 years: 0.96 male(s)/female
65 years and over: 0.8 male(s)/female
total population: 0.98 male(s)/female (2008 est.)

Bosnia and Herzegovina
at birth: 1.07 male(s)/female
under 15 years: 1.07 male(s)/female
15-64 years: 1.02 male(s)/female
65 years and over: 0.7 male(s)/female
total population: 0.97 male(s)/female (2008 est.)

Botswana
at birth: 1.03 male(s)/female
under 15 years: 1.03 male(s)/female
15-64 years: 1.02 male(s)/female
65 years and over: 0.68 male(s)/female
total population: 1.01 male(s)/female (2008 est.)

Brazil
at birth: 1.05 male(s)/female
under 15 years: 1.04 male(s)/female
15-64 years: 0.98 male(s)/female
65 years and over: 0.73 male(s)/female
total population: 0.98 male(s)/female (2008 est.)

British Virgin Islands
at birth: 1.05 male(s)/female
under 15 years: 1.03 male(s)/female
15-64 years: 1.05 male(s)/female
65 years and over: 1.07 male(s)/female
total population: 1.05 male(s)/female (2008 est.)

Brunei
at birth: 1.05 male(s)/female
under 15 years: 1.06 male(s)/female
15-64 years: 1 male(s)/female
65 years and over: 0.92 male(s)/female
total population: 1.02 male(s)/female (2008 est.)

Bulgaria
at birth: 1.06 male(s)/female
under 15 years: 1.05 male(s)/female
15-64 years: 0.97 male(s)/female
65 years and over: 0.69 male(s)/female
total population: 0.92 male(s)/female (2008 est.)

Burkina Faso
at birth: 1.03 male(s)/female
under 15 years: 1.01 male(s)/female
15-64 years: 0.99 male(s)/female
65 years and over: 0.66 male(s)/female
total population: 0.99 male(s)/female (2008 est.)

Burma
at birth: 1.06 male(s)/female
under 15 years: 1.03 male(s)/female
15-64 years: 0.98 male(s)/female
65 years and over: 0.75 male(s)/female
total population: 0.98 male(s)/female (2008 est.)