"One determining factor of future life satisfaction for their residents, which is less easy to predict, will be the trajectory of civil freedoms," she added in a press release.

The index looked at as many as 11 indicators, including GDP per head, life expectancy at birth, quality of family life, the state of political freedoms, job security, climate, safety, community life, governance and gender equality.

Among the 80 countries covered, Nigeria ranked last.