Does income inequality negatively affect GDP growth? A panel study

Abstract

Ricardo’s Distribution theory (1817) proposes that, as the economy faces diminishing profits/returns on capital, there would be an increasing shortage of investments. Income inequality exacerbates this problem, by causing income not to be reinvested back in production timely. Therefore, the result is a stagnant economy, where economic growth is significantly slowed down. Literatures on the relationship between income inequality or overall inequality, and economic growth, which is usually measured by GDP growth, have revealed different and robust results. Forbes, 2000 and Partridge, 1997 found a significantly positive correlation between income inequality and GDP growth. However, Tabellini et al, 1994 produced a significant and negative correlation. Interestingly, Squire et al, 1998 found no significant relationship between aggregate inequality and GDP growth, but a significantly negative relationship between poverty and GDP growth. More recently, Brueckner and Lederman, 2017 found a significantly negative impact of income inequality on GDP transitional growth in countries with high initial incomes. Nonetheless, overall, recent literature has been leaning towards the hypothesis that the relationship between income inequality and GDP growth is non-linear. This paper is going to empirically study 146 countries in the world over 27 years from 1992 to 2018, to confirm that the relationship between income inequality and GDP growth is non-linear as suggested in recent literature. Moreover, this research will show that the effects of income inequality on GDP growth is heterogeneous; the impact of income inequality on economic growth is more positive on high income countries than on lower income countries. The method used is regression that aims to explain the GDP movements of countries, in terms of consumption, export, capital formation, poverty, and GINI coefficient. This research is at preliminary level; there can be further improvements to the model.