Returns to scale to capital and the strength of capital externalities play a key role for the empirical predictions and policy implications of different growth theories. We show that both can be identified with individual wage data and implement our approach at the city-level using US Census...

Since the early 1980s, the U.S. economy has experienced a growing wage differential: high-skilled workers have claimed an increasing share of available income, while low-skilled workers have seen an absolute decline in real wages. How and why this disparity has arisen is a matter of ongoing...