Japan

Many population projections used by international and government agencies assume that, in today's low-fertility societies, future fertility rates will stop declining and roughly stabilize. This paper assesses the evidence for an equilibrium point or rebound from low levels. We show that there is no robust evidence for a systematic fertility rebound, or for a stable equilibrium point at any fertility level conventionally assumed. Instead, where and when fertility has fallen low, it has tended to keep falling. This is true across a range of data sources, time periods, and fertility measures: United Nations data on period total fertility rates for all country-years from 1950 to 2023; Human Fertility Database data on completed fertility for cohorts born between 1935 and 1975 in 31 countries; and fertility rates in subnational geographies in Japan, India, and the United States. We reconcile these results with a prior literature that documented fertility reversals among some low-fertility countries in the early 2000s. Our findings provide an empirical basis for re-examining the equilibrium and rebound assumptions embedded in widely used population projections.

This study examines the impact of demographic factors, particularly declining fertility rates and an aging population, on Japan’s economic growth from 1960 to 2022. Additionally, it analyzes key macroeconomic variables, including healthcare expenditure, interest rates, and inflation, that influence the country’s economy. Using quantitative time-series data and the Vector Error Correction Model (VECM), this research evaluates the short- and long-term effects of these variables on economic growth. The findings indicate that, in the long run, population aging and high interest rates significantly negatively affect economic growth. In contrast, healthcare expenditure and moderate inflation have a positive impact. Population aging slows economic expansion by increasing pension and healthcare costs, while high interest rates discourage investment and consumption. Conversely, healthcare expenditure, as an investment in human capital, enhances labor productivity, and moderate inflation stimulates economic activity by promoting consumption and investment. However, in the short term, none of these variables exhibit a significant impact on economic growth, suggesting that policy measures and demographic changes require time to influence the broader economy.

The shrinking of a city evokes an image that the amount of the main urban components, such as public facilities, infrastructure, and built-up areas, also shrinks. However, in reality, even in so-called shrinking cities with declining population, physical and spatial expansion is reported to continue and remain growth-oriented. This study examines whether some main urban components are shrinking in response to population and household decline by analyzing 1709 municipalities in Japan, around 80% of which have already experienced population decline over the past decade (2012–2022). The analyses use two datasets disclosing total quantities of respective urban components at the municipal level in the two endpoint years of 2012 and 2022, employing some simple techniques: correlation, simple regression analysis, and cross-tabulation. The results reveal that public facilities, road networks, and urban areas were supplied accordingly during periods of population growth but no corresponding downsizing occurs during periods of population decline; instead, several population-declining municipalities witness continuous expansion of these three urban components, contradicting the decrease in population and households. This tendency will create an imbalance between population and urban components, raising concerns that excessive public facilities, infrastructure, and urban areas disproportionate to population decline will undermine the efficiency of urban services and increase the burden on administrative and fiscal operations.

Highlights More than one third of married Japanese women report concerns about infertility, and infertility is increasingly cited as a reason for not reaching fertility ideals. Births conceived using medically assisted reproductive treatments have contributed to reducing the ideal–actual fertility gap by about one third. Infertility concerns are increasingly reported across alleducational groups, but highly educated women are more likely than others to seek and receive treatment.