Evolution of Sizes and Industrial Structure of Cities in Japan from 1980 to 2010: Constant churning and persistent regularity

This paper investigates the evolution of the Japanese economy between 1980 and 2010 from the viewpoint of population and industrial structure of cities. With the rural-to-urban transformation settling by the 1970s, Japan experienced the second stage of urbanization through the integration of nearby cities. This led, on average, to a disproportionate 24% population growth of a set of core cities. In the meantime, cities experienced substantial churning of industrial composition: on average, 35% of the three-digit manufacturing industries present in a city in 1980 had left by 2010, while on average, 30% of industries present in a city in 2010 were absent in the same city in 1980. Remarkably, these substantial relocations of population and industries among cities took place while preserving a simple yet rigid relationship between the size and industrial composition of cities characterized by the roughly constant elasticity between the number and average size of cities in which an industry was present. This paper discusses the policy implications of this persistent regularity and the possible underlying mechanisms.