This paper presents a model in which a country's measured average propensity to save endogenously rises when its economy industrializes. The model has agricultural and manufacturing sectors. Only agriculture uses land. If at early dates income per capita is low, agricultural consumption is important, land is valuable, and capital gains on land may constitute most wealth accumulation, leaving the country's NIPA APS low. If exogenous technological progress raises incomes over time, Engel's law shifts demand to manufactured goods. Then land's portfolio importance relative to reproducible capital diminishes and the national income and products account saving rate can rise.

To offer a possible interpretation for recent empirical findings on earnings growth, this paper constructs a simple model with endogenous human capital investment, a distribution of natural abilities, and unbiased technological progress. The model predicts that in the long run, average earnings within any education group will grow more slowly than average wages overall. It also predicts that average earnings in high‐education groups ultimately will rise relative to average earnings in low‐education groups. In the model, these processes do not imply secular increases in the degree of inequality in the overall cross‐sectional distribution of earnings.