Drivers of growth accelerations: What role for capital accumulation?

Economic growth is often episodic but the ultimate drivers of such growth accelerations are not understood very well. We therefore take a different perspective and investigate what happens to production factors and productivity before, during, and after 156 growth accelerations that we identify for 148 countries between 1950 and 2019. We are particularly interested in the role that physical capital accumulation can play in this context, given recent interest in investment surges and several investment-led growth models.

Our results show that physical capital accumulation accounts on average for 9% of the increase in the growth rate during an acceleration, with heterogeneity across regions, time periods, and the economies’ capital-output ratio. While growth accelerations are mainly driven by improvements in total factor productivity, we find that physical capital accumulation is an important factor for the sustainability of accelerations. Those findings are robust to various techniques for identifying growth accelerations and growth decompositions. They suggest that large “investment-led” growth accelerations are unlikely but also confirm that growth episodes that are not accompanied by solid investment patterns are likely to run out of steam.