The economy of Pakistan is the 24th largest in the world in terms of purchasing power parity (PPP), and 42nd largest in terms of nominal gross domestic product. Pakistan has a population of over 207 million  (the world’s 5th-largest), giving it a nominal GDP per capita of $1,629, which ranks 147th in the world for 2016. However, Pakistan’s undocumented economy is estimated to be 36% of its overall economy, which is not taken into consideration when calculating per capita income. Pakistan is a developing country and is one of the Next Eleven, the eleven countries that have a potential to be among the world’s large economies in the 21st century. However, after decades of war and social instability, as of 2013, serious deficiencies in basic services such as railway transportation and electric power generation had developed. The economy is semi-industrialized, with centres of growth along the Indus River. Primary export commodities include textiles, leather goods, sports goods, chemicals, carpets/rugs and medical instruments.