Figure 2. A Visualization of Global Income Distribution, 2007
(or latest available) in constant 2000 U.S. dollarsSource: Adapted from Sutcliffe (2005) using World Bank (2011), UNU-WIDER (2008) and Eurostat
(2011)
However, not all countries have distribution data. As Table 1
shows, we have data for 100 countries in 1990, 126 countries in
2000 and 135 countries in 2007 (Annex 2). Still under market
exchange rates, we now turn to a second approach to measuring
global income distribution, which is known as the inter-country
accounting model. This method looks at the average income
differences between large groupings of countries by treating all
members of a country as if they have the same income and then
dividing the world into population quintiles. This method is less
precise, but allows us to estimate global income distribution for
most of the world, a total of 182 countries in 2007. Figure 3 and
Table 3 present the income distribution results from 1990 to 2007.
Here, the wealthiest 20% of the population enjoyed more than 81%
of the world’s income as of 2007, with the poorest 20% holding on