Land Quality

We develop a new measure of land quality by estimating weights in a Poisson regression of population in grid cells on a vector of geographic characteristics and country fixed effects. Aggregating to the level of countries, we construct average land quality (ALQ) and quality-adjusted population density (QAPD). We establish several novel facts. First, current income per capita is positively correlated with ALQ. Second, while income today is unrelated to conventional population density, it is strongly negatively related to QAPD. Third, this negative relationship was not present in 1820 and emerged because today’s lower income countries have experienced faster population growth since then. Fourth, countries with higher average land quality began sustained modern economic growth earlier, and this earlier takeoff largely explains the ALQ -modern income relationship. We posit a framework in which higher land quality led to denser populations in Malthusian equilibrium and, via agglomeration effects, an earlier takeoff from that equilibrium. Less dense countries that took off later experienced larger multiplications of their populations over the course of the demographic transition due to the import of health technologies from countries that took off first.