Worlds apart: what polarization measures reveal about Sub-Saharan Africa's growth and welfare distribution in the last two decades

Sub-Saharan Africa's development path over the past two decades has been characterized by sluggish poverty reduction occurring alongside robust economic growth. While in this context we would expect inequality to increase, standard synthetic measures provide little evidence of a generalizable uptick in inequality over this period. We argue that the standard empirical toolkit available to development economists working on SSA has limited our ability to understand the role that distributional change plays in the persistence and reproduction of poverty on the continent. For this reason, we propose that supplementing inequality measures with the analysis of polarization provides a cleaner distributional lens through which to make sense of SSA's poverty performance during this period of growth. Applying polarization measures to comparable survey data from 24 Sub-Saharan African countries, we find that there has been a generalizable increase in polarization over the past two decades - and in particular, an increased concentration of households in the lower tail of the relative distribution. That this inegalitarian trend is overlooked when using standard synthetic inequality measures confirms our hypothesis that our current toolkit represents a technical bottleneck to understanding the effects of distributional trends on poverty reduction in Sub Saharan Africa - and that polarization analysis may help overcome this.