The decline in the physical stature of the American population for more than a generation beginning with the birth cohorts of the early 1830s was brought about by a diminution in nutritional intake in spite of robust growth in average incomes. This occurred at the onset of modern economic growth...

This paper shows that the explanation of the decline in the volatility of GDP growth since the mid-eighties is not the decline in the volatility of exogenous shocks but rather a change in their propagation mechanism.