A Study of Regional Sustainability in Japan : Migration, Economy, and Demographics

The regional population problem is one of the most critical challenges in the Japan, and there are many discussions about the problem. Even though the population comprises numerous factors such as population movement, agglomeration, and births, few discussions comprehensively handle these factors. To comprehensively discuss the relationship between the local population dynamics and the local economy, we first formulated the population entering the local labor market and the birth population as the outcome of spatial equilibrium. Combining population and economic data, we then decomposed the effects of factors affecting the local population dynamics by two-step estimations. Finally, based on the estimated population dynamics, population in prefectures in Japan is projected from 2015 to 2065. After evaluating credibility, two benchmark analyses and three counterfactual analyses are conducted to quantify the effects of factors that have been noted as affecting the local population: disparities of fertility, transportation networks, productivity.Consequently, the crowding effect of childcare in metropolitan areas and nationwide stagnation of productivity have caused a population loss of approximately millions. Furthermore, we have confirmed that regions that belong to neither metropolitan nor periphery areas are likely to experience the most significant population decline since these areas do not have the advantages that metropolitan and periphery areas have