World Population by Income
How Many Live on How Much, and Where
13% of people globally are middle income
People living on $10.01-20 daily are classified as middle income
The income groups are defined as follows: The poor live on $2 or less daily, low income on $2.01-10, middle income on $10.01-20, upper-middle income on $20.01-50, and high income on more than $50; figures expressed in 2011 purchasing power parities in 2011 prices.
Source: Pew Research Center analysis of data from the World Bank PovcalNet database (Center for Global Development version available on the Harvard Dataverse Network) and the Luxembourg Income Study database
Updated August 13, 2015: This new edition includes corrected estimates for Iceland, Luxembourg, the Netherlands and Taiwan, and some related aggregated data.