This paper analyzes trends in demographic shift from regional areas to large metropolitan areas, and economic factors resulting from this demographic shift. First, we analyzed the status of demographic shifts between the large metropolitan areas of Tokyo, Osaka and Aichi Prefectures, and then other individual prefectures for 5-year periods starting from 1970, 1980, 1990 and 2000, and for age segments of 5-14, 20-24, 25-64 and over 65 years. As a result, we observed population inflow from regional areas to the large metropolitan areas in Tokyo and Osaka Prefectures for the age segments up to 24 years old and population outflow from large metropolitan areas to regional areas for the age segments of 25-64 years, except for the period starting from 1970. As for Aichi Prefecture, the trends of population inflow from regional to metropolitan areas was observed since 1990 for the age segments above 25 years as well as the age segments up to 24 years
Next, we extracted “inflow populations to Tokyo, Osaka and Aichi Prefectures from other individual prefectures” as the ratio of inflow/outflow populations to each prefecture's population and “regional economic factors constituting the regional economy” as the ratio of each prefecture's factors against Tokyo, Osaka and Aichi Prefectures for the above-mentioned periods, and conducted attribution analyses with a multiple regression analysis approach. As for regional economic factors, we adopted 13 factors including industrial composition ratio, administrative investment, academic background index, sales turnover in retail industry that resulted in the economic factors attributing to demographic shifts for each period. The factors affecting the three large metropolitan areas most were the “tertiary industry ratio” , “industrial shipment value”, “administrative investment value” and “retail sales value”.
To control population outflows from regional areas to large metropolitan areas in the future, upgrading industrial structure, turning from a reliance on public works and improving intellectual levels should be important.
JEL Classification: R00, R1
