Changes in the world income distribution

Drawing on new international comparison estimates for 127 nations, this study examines in some detail for the decinnial years 1950–1980 the world size distribution of income. Different income concepts—national output valued in different ways, and also consumption alone; and income per-equivalent adult as well as per capita—have been considered in judging how world inequality has changed. The principal findings are: (i) at a point in time, the intercountry differences in income—differences among nations—are greater than the usually observed intracountry differences in income—differences within nations; and (ii) over time systematic differences in national economic growth rates of countries led on balance to very slightly increased intercountry inequality (quite possible not beyond the margin of measurement error) but that (and this judgment is quite tentative) the changes in intracountry inequality over time have left inequality in the overall distribution unchanged.