There have been many studies about structural changes of the three major metropolitan areas in Japan. One of the indexes to estimate these changes is commuting flow. This has changed from intensive concentration of trips to the central city to a more complex pattern because of the increase of intra-suburban trips.
The purpose of this study is to consider the changes in commuting flow in the three major metropolitan areas in Japan in terms of cohort size and female labour using longitudinal data on residential, occupational and family careers and cohort analysis. The results of the analysis are summarized as follows:
(1) Demographic features of the three major metropolitan areas in Japan
The three major metropolitan areas in Japan, Tokyo, Osaka and Nagoya have similar age structures in which specific cohorts born between 1935 and 1950 are notable for their large concentrations in the suburbs. Those included in these cohorts migrated into metropolitan centers from the non-metropolitan area during the period of rapid economic growth (1960s) and after that they moved to metropolitan suburbs at the time of marriage or childbirth.
(2) Differences of occupational career between husband and wife in the metropolitan suburbs
To clarify the differences of occupational career between husband and wife, longitudinal data collected through a retrospective survey in Kozoji New Town, a suburb of Nagoya, is analysed.
When households moved into the suburbs, many husbands continued to commute to the metropolitan center. On the other hand, many wives quit their jobs because of impending childbirth and child-rearing. After child-rearing, wives obtained employment, often part-time work near their home because getting a full-time job or commuting to the metropolitan center was difficult on account of the heavy responsibility of housework.
(3) Changes in commuting flow in the metropolitan suburbs
Commuting flows at the macro level are discussed using cohort analysis in Saitama prefecture, a suburb of Tokyo, in order to show that the individual commuting activity, as mentioned above, has contributed to changes in commuting flow in the metropolitan area.
From the 1960s through to the early 1970s a large number of people born between 1935 and 1950 flowed into metropolitan suburb due to marriage or childbirth. Although men continued to commute to metropolitan center, women quit their jobs. Therefore only commuters to the metropolitan center increased at that time.
After the mid-1970s women who had moved to the metropolitan suburbs completed child-rearing and got employment again near their home. Therefore middle-aged female workers, who constitute the bulk of intra-suburban commuters, increased rapidly.
It should be concluded that the changes in commuting flow in the three major metropolitan areas result from the life-cycle changes of women suburbanites born between 1935 and 1950.
(4) Demand side factors in the labour market
Concerning the rapid increase of middle-aged female labour there are also several demand side factors. One is the demand for white-collar workers and another is the demand for blue-collar workers. As for the later, secondary industry changed its employment structure from young women to middle-aged women part-timers after the first oil crisis.

View full abstract

In this article, I discuss how the family activities of automobile manufacturing workers from Toyota Motor Corporation (Toyota) are influenced by the transformation of production projects. Because of the poor economic situation of the 1990s in Japan, the automobile manufacturing section at Toyota put a system of time management into force as a part of its restructuring programme. After the time management system had been enforced, the family activities and gender divisions in households of the manufacturing workers in this section changed to a certain extent. Here, for the methodology, I use the project concept from‘time geography’based on time-space budgeted data, and try to examine the relations between the production project and family projects.
In the second section of this paper, I explain the production project by Toyota and its transformation. The production project strongly influences the activities of the workers. During working hours, the workers are constrained by severe coupling with the production line. Moreover, the daily paths of the workers are determined by the persistence of holiday working, shift changes, and overtime work as an aspect of human resource flexibility within the Toyota production system. During the period of Japanese high-growth, Toyota centrally determined the workers day and night shift system (day shift 8:00∼17:00, night shift 21:00∼6:00) and overtime work. In recent years, the need for cost reduction and improvements in employment efficiency were required due to the change of economic trends in the international market and to changes in Japanese society. This situation caused the appearance of another working pattern, such as the sequential two shift system (1st shift 6:30∼15:15, 2nd shift 16:15∼1:00).
In the third section of this paper, I clarify the sharing activities of the workers in the family project. For the sharing activities, I chose the meal activities and going-out activities of family members. The activity patterns of wife and husband match in the day shift and reverses in the night shift. This pattern changes week by week. It is thought of as continuous activity, most of the worker's families take their meal together in the evening despite this weekly cycle. It remains, however, that the going-out activities are rarely done by them together. It seems that the production project is a significant factor of constraint for the husband doing any activities other than working. Because of the transformation to the sequential two shift system, the activity patterns of wife and husband do not match anymore and so they have a difficulty even in sharing the meal together. However, the husbands have joined shopping activities with their families.
In the fourth section of this article, I discuss the division of household activities of the workers in the family project. For instance, I chose some pickup and send-off activities for their children and I tried to explain the change of gender division of household activities. When the day and night shift system was in place it was impossible the for wife and husband to share the household activities and childcare. Therefore, the wife had to do all the household activities. However, after the sequential two shift system was introduced, husbands began to do household activities such as pickup and send-off activities for their children. Thus, the changes of gender division of household activities became evident. As a consequence, the flexibility of the production project was weakened in daily scale but that of the family project was increased.

View full abstract