Does Volunteering Reduce Mortality? Evidence from a Natural Experiment in Japan∗

Volunteering is a widespread economic activity across the world. Although volunteering is likely to contribute to the society, research on social returns to volunteering is scarce. In this paper, we explore the causal effect of volunteering which mainly targets the elderly on mortality at city level. A potential threat for identification is endogeneity of volunteering. Specifically, unobserved heterogeneity such as the quality of local health care service may affect both mortality and the level of volunteering. Furthermore, there may be more volunteers in cities with a large number of vulnerable people. In order to identify the causal effect of volunteering, we use exogenous variation in volunteering caused by the Great Hanshin-Awaji Earthquake which occurred in the Midwestern part of Japan in 1995. Using the instrumental variable estimator, we find that one percent increase in the number of volunteers reduces the number of deaths due to natural causes by about 0.13 percent.