The evolution of wealth inequality over half a century: the role of skills, taxes and institutions

Over the last 50 years, the US economy saw significant changes in its fiscal structure. Notable among these are the introduction and expansion of social security programs and Medicare, and the transformation of the tax system. These institutional changes took place against a backdrop of developments in the technology of production that increasingly favored skilled workers.In this paper, we analyze how the interplay between these institutional and technological factors might have shaped the distributions of income, wealth, consumption and welfare. We find that while changes in income inequality are mostly attributable to technological factors, the increase in wealth inequality has further been compounded by the expansion of social security and Medicare, which have reduced saving incentives for retirement, in particular for low and middle income groups. As a result, they have substantially increased wealth concentration in US. Results suggest that approximately 25% of the rise in the share of wealth held by the wealthiest 1% is explained by larger transfers to senior population.