Effects of longevity and dependency rates on saving and growth: Evidence from a panel of cross countries

While earlier empirical studies found a negative saving effect of old-age dependency rates without considering longevity, recent studies have found that longevity has a positive effect on growth without considering old-age dependency rates. In this paper, we first justify the related yet independent roles of longevity and old-age dependency rates in determining saving and growth by using a growth model that encompasses both neoclassical and endogenous growth models as special cases. Using panel data from a recent World Bank data set, we then find that the longevity effect is positive and the dependency effect is negative in savings and investment regressions. The estimates indicate that the differences in the demographic variables across countries or over time can well explain the differences in aggregate savings rates. We also find that both population age structure and life expectancy are important contributing factors to growth.