[Image:HDImap spectrum2006 Africa.png|thumb|260px| [Image:Esperanza de vida.PNG|thumb|300px| map of world life expectancies The population of Africa has grown rapidly over the past century, and consequently shows a large youth bulge, further reinforced by a low life expectancy of below 50 years in some African countries. The population doubled in the period 1982–2009 and quadrupled from 1955–2009, according to United Nations estimates. As of 2013, the total population of Africa is estimated at 1.1 billion, representing approximately 15% of the world's population.