2011 per capita income gap between rich and the developing nations was back to where it was in 1950
"In fact, the per capita income gap between the advanced and the developing economies steadily widened from 1950 until 2000. There were a few pockets of countries that did catch up with the West, but they were limited to oil states in the Gulf, the nations of southern Europe after World War II, and the economic "tigers" of East Asia. It was only after 2000 that the emerging markets as a whole started to catch up; nevertheless, as of 2011, the difference in per capita incomes between the rich and the developing nations was back to where it was in the 1950s."
Source: Ruchir Sharma, "Broken BRICs," Foreign Affairs, Nov.-Dec 2011. http://www.foreignaffairs.com/articles/138219/ruchir-sharma/broken-brics... [verified 4/17/14]