Yohei Maruyama: What the Population Influx and "Singularization" of Tokyo's Special Wards Pose

2024/10/23

In April 2024, Toyo Keizai Inc. published "The Shock of Middle-Age Singles in Tokyo: The Future of a 'Solo' Society." The middle-age period refers to those aged 35 to 64, an age group previously assumed to naturally marry and form families, but which is now seeing an increase in single individuals. This book focuses on the fact that this "singularization" of the middle-age population is particularly prominent in Tokyo's special wards. It analyzes the reasons and social impacts, attempting to propose a framework for the challenges we must address. As a co-author, I was responsible for Chapter 2, "Migration to Tokyo's Special Wards and Singularization," from the perspective of population movement. Since publication, I am grateful that the book has been featured in various media through book reviews and other outlets, which led to this opportunity to write this piece.

The starting point for the research on middle-age singles in this book was a three-year study on the lives of single residents conducted starting in FY2013 at the Shinjuku Institute for Local Autonomy within the Shinjuku Ward Office. Having just completed my Doctoral Programs coursework, I was involved as a part-time researcher. While the increase in elderly singles was recognized as a social issue, the fact that middle-age singles were also increasing significantly was largely overlooked, as they were generally perceived as a generation with few problems. In this context, Shinjuku Ward had a strong sense of urgency because the single rate of its middle-age population was exceptionally high nationwide, and these individuals would eventually become elderly singles as they aged. A survey was conducted to clarify their actual living conditions. As a result, the diverse realities of middle-age singles in the central Tokyo area of Shinjuku were brought to light. It also became clear that there is a segment requiring urgent support in terms of economic risk and social isolation risk.

Following this research in Shinjuku, a two-year research project titled "Analysis of Small-Area Population and Households in Special Wards and the Current Status and Challenges of Single Persons in Prime Working Age" was carried out from FY2019 at the Research Institute for Special Wards to capture the living conditions of middle-age singles across Tokyo's special wards more broadly. In addition to macro-level population and household analysis of the special wards, we conducted attitude surveys and interviews in Setagaya, Toshima, and Sumida Wards. The research results, which closely examined the human relationships and daily lives of middle-age singles, led to this publication.

Throughout this series of studies, I have been responsible for macro-level regional population analysis regarding the impact of population movement on the progress and prominence of singularization in Tokyo's special wards. While Shinjuku and other special wards continue to see population inflows from surrounding areas and regional zones, they also have low birth rates and are areas where the singularization of the middle-age population is prominent. How these elements are interrelated is the analytical perspective I have maintained. Below, I would like to consider how Tokyo's special wards will transform due to middle-age singularization, based on the reality of population movement and singularization in the wards from this perspective.

Let's look at the situation in Tokyo's special wards using specific data. To state the conclusion first, when comparing middle-age residents of Tokyo's special wards who are from within the Tokyo metropolitan area with those from outside, the latter have a higher single rate. This indicates that population movement between the Tokyo metropolitan area and regional areas is linked to the prominence of singularization in Tokyo's special wards.

Calculating the middle-age single rate from the Census, the national figure in 1980 was 4.7%. As shown by the fact that it was below 5%, approximately 40 years ago, the vast majority of middle-aged people were married and had their own families; singles were a minority. That single rate has been rising, driven by the progress of the trend toward remaining unmarried and changes in family formation behavior, such as later marriage or non-marriage. There are also regional differences in middle-age singularization, which is more prominent in the Tokyo metropolitan area and Tokyo's special wards. In 1980, the rates were 4.7% nationally, 5.7% in the Tokyo metropolitan area, and 9.4% in Tokyo's special wards. In 2020, they were 15.8%, 19.1%, and 27.5%, respectively. The increases over 40 years were 11.1 points, 13.4 points, and 18.1 points. It is clear that the middle-age single rate in Tokyo's special wards is at an overwhelmingly high level even when looking at chronological changes.

Why has middle-age singularization become so prominent in Tokyo's special wards? Let's consider this in relation to population movement. Driven by a large net migration gain, the population of Tokyo's special wards continues to increase. Changes have occurred in the age patterns of this net migration. Until around the bubble economy era, the age pattern for Tokyo's special wards and the Tokyo metropolitan area showed a net inflow from the late teens to early 20s, and a net outflow from the late 20s onwards. This reflected migration for education or employment in the former case, and return migration such as "U-turns" in the latter. However, entering the 21st century, net inflows have continued into the 30s and beyond, and the trend of middle-age population concentration in Tokyo's special wards and the Tokyo metropolitan area has strengthened. This has also become the pattern of population movement driving the recent "return to the city center" trend.

What I considered here is the relationship where, among the middle-age population living in Tokyo's special wards, those from outside the Tokyo metropolitan area have a higher single rate than those from within. This led to the hypothesis that population movement promotes singularization. There is a wealth of international research on the relationship between migration experience and family formation behavior, and in Japan, it has been shown that those with experience moving to major metropolitan areas have lower birth rates or higher lifetime non-marriage rates. I thought the same framework could be applied to middle-age singularization.

To clarify this relationship, I combined the results of the Migration Survey by the National Institute of Population and Social Security Research with the Census to estimate and classify the single rate of the middle-age population living in Tokyo's special wards into those from within the Tokyo metropolitan area and those from outside. Unfortunately, since the Migration Survey data is only available at the prefectural level, I substituted Tokyo Metropolis data for the situation in Tokyo's special wards.

Figure 1 shows the results. For both men and women, the single rate for those from outside the Tokyo metropolitan area was higher than for those from within. In other words, the population group that moves from outside the Tokyo metropolitan area to Tokyo's special wards and contributes to the return to the city center has the effect of promoting the singularization of Tokyo as a whole. For the six points in time where data estimation was possible, the gap in the single rate based on place of origin was 4.3 to 11.1 percentage points for men and 0.9 to 3.1 percentage points for women, showing that the gap is larger for men. Men also have a higher overall level of singlehood, meaning that the effect of inward migration from outside the Tokyo metropolitan area in raising Tokyo's single rate is significant.

I would like to consider the fact that middle-age populations moving from outside the Tokyo metropolitan area are becoming more singularized from the perspective of life course diversity. Modern society is one of increasing diversity. Living alone in middle age can be seen as one result of a diversified life course. While it may not necessarily be the life course one imagined, it also reflects a shift away from a society that forces the uniform family formation of the so-called "standard family" (a salaryman husband, a stay-at-home wife, and two children).

Uniform life courses, especially those with strong traditional norms, still have remnants—relatively speaking—in regional areas, particularly those that can be described as "the countryside." Perhaps the meaning of escaping from negative images, such as the consciousness of gender-based division of labor that is close to sexism, has come to be more strongly reflected in population movement from regional areas to Tokyo's special wards. I believe that people attempting such moves are thinking of breaking away from uniformity and thirsting for diversity, with the hope that an environment that tolerates diversity exists more in major metropolitan areas—especially Tokyo's special wards—than in regional areas.

However, the tolerance for diversity in major metropolitan areas is only relatively high and cannot necessarily be said to have reached a necessary and sufficient level. This is evident, for example, in recent discussions on work-life balance and remote work, or discussions on gender and sexuality. Nevertheless, if it is "better" than in regional areas, the population influx into the Tokyo metropolitan area and Tokyo's special wards will likely continue, and the living realities of the single population will likely diversify further accordingly.

Into what kind of region will Tokyo's special wards, with their many middle-age singles, transform? First, there will likely be a further increase in middle-age singles who do not have families in the future and are prone to social isolation. Furthermore, some of them may be placed in unstable economic situations due to non-regular employment, potentially giving rise to a new underclass. If such people reach old age, Tokyo's special wards may turn into places where people living precarious lives reside together.

On the other hand, if we view the increase in middle-age and elderly singles positively and can create various services for singles through public-private collaboration, there is a possibility that Tokyo's special wards could lead the way as a single-friendly region. If it becomes a place where people can enjoy the freedom to actively choose to be single rather than choosing marriage, it will likely become a society that broadly and deeply tolerates diversity in its formation process. This might lead to further singularization of those from within the Tokyo metropolitan area and an increase in the influx of singles from outside the area.

In any case, it is certain that middle-age singles will increase nationwide, and Tokyo's special wards will likely become a place that constantly faces the new social challenges brought by singles and seeks answers to them.