An excerpt from Paul Ormerod's, Why Most Things Fail:
Here, the source:
... are completely wrong when they repeatedly assert that the world as a whole is becoming more unequal. for the first time in the history of capitalism, the distribution of world income between countries became more equal in the second half of the twentieth century, and in particular during its final quarter. The economic successes in Asia have liberated many, many millions of people lives of unremitting drudgery and toil, and have reduced world income inequality. But, just as with the movements over time in inequality within nations, changes in global inequality have not happened smoothly...
... The recent changes in inequality within countries such as South Korea an China mirror the evolution of global inequality over the past two centuries. In the 1950s, South Korea was a poor but very egalitarian society. During its phase of phenomenal growth, inequalities opened up and its Gini coefficient approached 40 (0 = complete equality, 100 = total inequality). Now that South Korean income is close to average income level in the West, prosperity is being more widely shared, and the Gini has dropped back to the low 30s.