A report by World Bank has indicated that the average life expectancy in Nigeria, which was put at 52 years as of 2011, is the 17th lowest in the world.
Analysis of the report showed that the last 20 countries were mainly Sub-Saharan African countries, except Afghanistan, where the average life expectancy was put at 49 years.
According to the report, five African countries, Sierra Leone, Lesotho, Democratic Republic of Congo, Guinea Bissau and Central African Republic, ranked lowest in life expectancy with 48 years.
About 30 countries, mostly in Europe, have average life expectancy of 80 years and above, with Switzerland and Hong Kong having the highest average of 83 years.
The report, which compared life expectancy in 1990 and in 2011, showed that most countries improved over the period of about two decades.
The world average life expectancy rose from 65 years in 1990 to 70 years in 2011.
For low-income regions, it rose from 53 years to 59 years, whereas in the middle-income regions, it rose from 64 years to 69 years.
In 2011, the life expectancy average for Sub-Saharan Africa stood at 55 years, 66 years in South Asia, 72 years in Middle East and North Africa, 74 years in Latin America and Caribbean, 72 years in Europe and Central Asia and 72 years in East Asia and the Pacific.
The Euro area had the highest regional average of 81 years.
For Nigeria, the average life expectancy rose from 46 years in 1990 to 52 years in 2011.
World Bank records have it that the figure for males is 51 years while that of females is 53 years.
The report also showed that infant mortality rate dropped from 126 per 1000 live births in 1990 to 78 per 1000 live births in 2012.
Further analysis showed that Nigeria had the 7th highest infant mortality rate in the world as of 2012.
The countries that had higher infant mortality rates as of 2012 were Sierra Leone with 117 per 1000 live births, Angola 100, Democratic Republic of Congo 100, Chad 89, Guinea Bissau 81, and Mali 80.
Under-five mortality rate in Nigeria dropped from 213 per 1000 live births in 1990 to 124 per 1000 live births in 2012.
The report also showed that in Nigeria, men died more than women between 2006 and 2011.
It put the adult mortality rate for males in Nigeria within the period at 387 per 1000.