"The "developing world's middle class" is defined here as those who are not poor when judged by the median poverty line of developing countries, but are still poor by US standards. The "Western middle class" is defined as those who are not poor by US standards. Although barely 80 million people...

In Asia inequality in income between countries is more important than inequality within countries. In Africa, Latin America, and western Europe and North America, by contrast, there are only small differences between countries; inequality within countries is more important. And when countries...