Elasticity of Economic Development and Child Mortality, 1950-2011

Andrew Noymer, University of California, Irvine
Danzhen You, Harvard University
Haruka Hatori, University of California, Irvine

We construct "Preston curves" depicting the relationship between child mortality (5q0) and economic development, using all available years of data from the UN Inter-agency Group for Child Mortality Estimation and the Penn World Table, for real GDP per capita. Unlike the classical curves for life expectancy, we use log-log scale, which gives a better fit. This has the advantage that the slope coefficient is directly interpretable as an elasticity, viz., the percentage change (decline) in child mortality for a one-percent increase in per capita GDP. This elasticity has been reasonably stable during the 62-year time span. If we think of income as "buying" lower child mortality, then we must realize that relative improvements in 5q0 (elasticities) have not become more favorable in the long run. This has implications for full achievement of MDG 4; however, under 5 mortality rates continue to decline, even at the lowest levels of per-capita income.