A Polarization of Polarization? The Distribution of Inequality 1970-1996

This paper presents a panel of internationally comparable Gini coefficients, based on the United Nations University/World Institute for Development Economics Research (UNU/WIDER) World Income Inequality Database (WIID) version 1.0. The 221 data points that match minimum requirements of spatial and temporal homogeneity cover 67 developed and developing countries and span a twenty-six year period, from 1970 to 1996. Density functions for the Gini coefficients are estimated for selected points in time in order to evaluate how the distribution of inequality has evolved in the recent past: the aim is to offer a concise description of the evolution of polarization of societies in the world. The distribution of inequality appears to be slightly bimodal at the start of the period: alongside a sizable concentration of countries with average levels of distributional asymmetry, there is a smaller one of very unequal nations, mainly located in Latin America. In the following two decades polarization levels are more homogeneous, suggesting a convergence of class structure across states. In recent times, there has been a resurgence of bimodality; the rise in the number of highly polarized, strongly conflictual societies has been driven by transition frictions in the ex-USSR area