21.9 years (2008 est.)

Nepal
total: 20.7 years
male: 20.5 years
female: 20.8 years (2008 est.)

Netherlands
total: 40 years
male: 39.2 years
female: 40.9 years (2008 est.)

Netherlands Antilles
total: 33.4 years
male: 31.6 years
female: 35.2 years (2008 est.)

New Caledonia
total: 28.4 years
male: 28 years
female: 28.8 years (2008 est.)

New Zealand
total: 36.3 years
male: 35.6 years
female: 37.1 years (2008 est.)

Nicaragua
total: 21.7 years
male: 21.3 years
female: 22.1 years (2008 est.)

Niger
total: 16.4 years
male: 16.5 years
female: 16.4 years (2008 est.)

Nigeria
total: 18.9 years
male: 18.8 years
female: 19 years (2008 est.)

Northern Mariana Islands
total: 29.9 years
male: 32 years
female: 28.9 years (2008 est.)

Norway
total: 39 years
male: 38.2 years
female: 39.9 years (2008 est.)

Oman
total: 18.9 years
male: 21.3 years
female: 16.6 years (2008 est.)

Pakistan
total: 20.5 years
male: 20.3 years
female: 20.6 years (2008 est.)

Palau
total: 32.3 years
male: 33.3 years
female: 31.3 years (2008 est.)

Panama
total: 26.7 years
male: 26.3 years
female: 27.1 years (2008 est.)

Papua New Guinea
total: 21.5 years
male: 21.6 years
female: 21.4 years (2008 est.)

Paraguay
total: 21.7 years
male: 21.5 years
female: 22 years (2008 est.)

Peru
total: 25.8 years
male: 25.5 years
female: 26.1 years (2008 est.)

Philippines
total: 22.3 years
male: 21.8 years
female: 22.8 years (2008 est.)

Poland
total: 37.6 years
male: 35.8 years
female: 39.5 years (2008 est.)

Portugal
total: 39.1 years
male: 37 years
female: 41.3 years (2008 est.)

Puerto Rico
total: 35.6 years
male: 33.8 years
female: 37.3 years (2008 est.)

Qatar
total: 30.7 years
male: 32.8 years
female: 25.4 years (2008 est.)

Romania
total: 37.3 years
male: 35.9 years
female: 38.7 years (2008 est.)

Russia
total: 38.3 years
male: 35.1 years
female: 41.4 years (2008 est.)

Rwanda
total: 18.7 years
male: 18.5 years
female: 18.9 years (2008 est.)

Saint Helena
total: 37.1 years
male: 37.2 years
female: 37 years (2008 est.)

Saint Kitts and Nevis
total: 28.4 years
male: 27.7 years
female: 29.1 years (2008 est.)

Saint Lucia
total: 29.2 years
male: 28.2 years
female: 30.2 years (2008 est.)

Saint Pierre