Revisiting capital-skill complementarity, inequality, and labor share

Abstract

This paper analyzes the quantitative contribution of capital-skill complementarity in accounting for rising wage inequality, as in Krusell, Ohanian, Rios-Rull, and Violante (KORV, 2000). We study how well the KORV framework accounts for more recent data, including the large changes in labor's share of income that occurred after the KORV estimation period ended. We also study how using information and communications technology (ICT) capital as the complementary capital stock affects the model's implications for inequality and overall model fit. We find significant evidence for continued capital-skill complementarity across all model permutations we analyze. Despite nearly 30 years of additional data, we find very little change to the original KORV estimates of substitution elasticities when the total stock of capital equipment is used as the complementary capital stock. We find much more capital-skill complementarity when ICT capital is used. The KORV framework continues to closely account for rising wage inequality through 2019, though it misses the three percentage points decline in labor's share of income that has occurred since 2000.