To rationalize a substantial income share of labor despite progressive task automation over the centuries, we present a simple model in which demand moves along a vertically differentiated production structure toward goods of increasing sophistication. Automation of more sophisticated goods...

Standard economic theories have severe difficulties in simultaneously explaining a number of key aggregate empirical facts: i) there are substantial differences in capital-labor ratios across time ii) despite continuously increasing capital-labor ratios, both factors still earn non-negligible...