This paper examines the mechanism of the aging of the population in the suburbs of Metropolitan Tokyo. Most suburban residents at this time are not greying, but a report based on a recent population projection which used the cohort component method indicates that these districts have a high probability of a rising population ratio of residents aged 65 and over.
Most ages of residents concentrate on particular cohorts, especially on residents who were born in the 1935-1955 period. Thus, an accelerated rise in this ratio is unavoidable as the population ages.
However, second-generation residents of these districts are showing particular patterns of migration.
For example : (1) Second-generation residents move out of their residential districts, and (2) new residents of the same second-generation age move into these districts.
In the suburbs of Metropolitan Tokyo, the residents mainly consist of cohorts born in the 1935-1955 period plus their children, and most of the residential districts belong to migration pattern (1). In the future, most of these districts will be occupied by first-generation residents, so the suburbs are expected to grey with their aging. Therefore, although aging progresses differently from district to district, a long-term perspective indicates that these processes seem more likely to be dominant in greying residential districts.
Already in some districts, those who leave are first-generation residents ; thus it is difficult to maintain the infrastructure these areas require. As a result, empty houses and vacant parking spaces increase due to depopulation. The fear therefore arises that a population decrease will accelerate the frequency of moves to other districts by the residents of these areas.
