How has the global distribution of fertility changed over time?

The chart below plots the global distribution of fertility (as measured by the TFR) in 1960 and 2012, using data from the World Bank. As is widely known, fertility has declined substantially over the last fifty years. In 1960, the median state was Albania, with a TFR of 6.2. In 2012 by contrast, the median state was Sri Lanka, with a TFR of 2.3. Nevertheless, there are still a considerable number of states with rapidly growing populations. In 2012, 35% of states had a TFR greater than 3, 23% had a TFR greater than 4, and 10% had a TFR greater than 5. One particularly noteworthy case is Nigeria, which in 2012 had a TFR of 6 and a population of 169 million. At its present rate of growth, the country will be about as large as the United States is now by 2034.