Approximately 36.5 million people in Japan were estimated to be within the age group 65 and over in 2024. This number was projected to increase until 2040 and then decline to about 20.1 million by 2120.

In 2023, there were around *** live births per 1,000 inhabitants in Japan, down from about *** in the previous year. The total number of live births in the nation amounted to approximately ******* in 2023. Japan’s super aging society Directly after the end of WWII, the live birth rate in Japan was over ** per 1,000 of population. The rate has constantly dropped in the last decades after the second baby boom (between 1971 and 1974). Meanwhile, the life expectancy of the Japanese people has increased, reaching about **** years for women and **** years for men in 2022. Due to the combination of both factors, Japan has developed into one of the most rapidly aging societies in the world. Almost ** percent of Japan’s population is currently aged 65 years and older, falling into the “super-aged nation” defined by international institutions and organizations.  Decreasing number of marriages In Japan, the number of births outside of marriage is small. The Japanese government, therefore, considers the decreasing number of marriages as the driving factor behind the country’s fertility decline. As of 2023, the number of marriages per 1,000 Japanese citizens was ***, less than half compared to that in the early *****. The average age of first marriage has also risen for both men and women. This trend can be partially attributed to the increasing number of employed and therefore financially and socially independent women in the past two decades. The employment rate of women in Japan exceeded ** percent for the first time in history in ****.

Historical chart and dataset showing total population for Japan by year from 1950 to 2025.

In 1800, the population of Japan was just over 30 million, a figure which would grow by just two million in the first half of the 19th century. However, with the fall of the Tokugawa shogunate and the restoration of the emperor in the Meiji Restoration of 1868, Japan would begin transforming from an isolated feudal island, to a modernized empire built on Western models. The Meiji period would see a rapid rise in the population of Japan, as industrialization and advancements in healthcare lead to a significant reduction in child mortality rates, while the creation overseas colonies would lead to a strong economic boom. However, this growth would slow beginning in 1937, as Japan entered a prolonged war with the Republic of China, which later grew into a major theater of the Second World War. The war was eventually brought to Japan's home front, with the escalation of Allied air raids on Japanese urban centers from 1944 onwards (Tokyo was the most-bombed city of the Second World War). By the war's end in 1945 and the subsequent occupation of the island by the Allied military, Japan had suffered over two and a half million military fatalities, and over one million civilian deaths.

The population figures of Japan were quick to recover, as the post-war “economic miracle” would see an unprecedented expansion of the Japanese economy, and would lead to the country becoming one of the first fully industrialized nations in East Asia. As living standards rose, the population of Japan would increase from 77 million in 1945, to over 127 million by the end of the century. However, growth would begin to slow in the late 1980s, as birth rates and migration rates fell, and Japan eventually grew to have one of the oldest populations in the world. The population would peak in 2008 at just over 128 million, but has consistently fallen each year since then, as the fertility rate of the country remains below replacement level (despite government initiatives to counter this) and the country's immigrant population remains relatively stable. The population of Japan is expected to continue its decline in the coming years, and in 2020, it is estimated that approximately 126 million people inhabit the island country.

Historical chart and dataset showing Japan population growth rate by year from 1961 to 2023.

The statistic shows the total population in Japan from 2020 to 2024, with projections up until 2030. In 2024, the total population of Japan amounted to around 123.89 million inhabitants. See the figures for the population of South Korea for comparison. Total population in Japan From steadily low fertility rates to a growing elderly population, it is no secret that Japan’s population is shrinking. Population growth rates jump around a little, but are currently following a declining trend. The post-war baby boom generation is now in the 65-and-over age group, and the percentage of the population in that category is expected to keep growing, as is indicated by a high median age and high life expectancy. Japan already has the highest percentage of its population over 65 in the world, and the aging population puts some pressure on the Japanese government to provide welfare services for more people as rising numbers leave the workforce. However, the amount of jobs opened up for the younger generations by the older generations leaving the workforce means that unemployment is kept to a minimum. Despite a jump in unemployment after the global recession hit in 2008, rates were almost back to pre-recession rates by 2013. Another factor affecting Japan is the number of emigrants to other countries. The United States absorbs a number of emigrants worldwide, so despite a stagnating birth rate, the U.S. has seen a steady rise in population.

As of 2024, the total population in Japan was estimated to be approximately ********************. The projection for 2100 indicated an almost ** percent decrease in population to around **** million people.

Throughout the Common Era, Japan's population saw relatively steady growth between each century. Failed invasions and distance from Asia's mainland meant that Japan was unaffected by many pandemics, primarily bubonic plague, therefore its development was not drastically impeded in the same way as areas such as China or Europe. Additionally, religious practices meant that hygiene was prioritized much more in Japan than in other regions, and dietary customs saw lower rates of meat consumption and regular boiling of water in meals or tea; both of these factors contributed to lower rates of infection for many parasitic or water-borne diseases. Fewer international conflicts and domestic stability also saw lower mortality in this regard, and Japan was an considered an outlier by Asian standards, as some shifting trends associated with the demographic transition (such as lower child mortality and fertility) began taking place in the 17th century; much earlier time than anywhere else in the world. Yet the most significant changes came in the 20th century, as Japan's advanced healthcare and sanitation systems saw drastic reductions in mortality. Challenges Japan's isolation meant that, when pandemics did arrive, the population had less protection and viruses could have higher mortality rates; smallpox has been cited as the deadliest of these pandemics, although increased international contact in the late 19th century brought new viruses, and population growth slowed. Earlier isolation also meant that crop failure or food shortages could leave large sections of the population vulnerable, and, as mentioned, the Japanese diet contained relatively little meat, therefore there was a higher reliance on crops and vegetables. It is believed that the shortage of arable land and the acidity of the soil due to volcanic activity meant that agriculture was more challenging in Japan than on the Asian mainland. For most of history, paddy fields were the most efficient source of food production in Japan, but the challenging nature of this form of agriculture and changes in employment trends gradually led to an increased reliance in imported crops. Post-Sakoku Japan Distance from the Asian mainland was not the only reason for Japan's isolation; from 1603 to 1853, under the Tokugawa shogunate, international trade was restricted, migration abroad was forbidden, and most foreign interaction was centered around Nagasaki. American neo-imperialism then forced Japan to open trade with the west, and Japan became an imperial power by the early-1900s. Japanese expansion began with a series of military victories against China and Russia at the turn of the century, and the annexation of Taiwan, Korea, and Manchuria by the 1930s, before things escalated further during its invasion of China and the Second World War. Despite its involvement in so many wars, the majority of conflicts involving Japan were overseas, therefore civilian casualties were much lower than those suffered by other Asian countries during this time. After Japan's defeat in 1945, its imperial ambitions were abandoned, it developed strong economic ties with the West, and had the fastest economic growth of any industrial country in the post-WWII period. Today, Japan is one of the most demographically advanced countries in the world, with the highest life expectancy in most years. However, its population has been in a steady decline for over a decade, and low fertility and an over-aged society are considered some of the biggest challenges to Japanese society today.

In 2023, the total population in Japan slightly decreased to just below 125 million people compared to the previous year, with the female population reaching around 63.9 million, as compared to 60.5 million men. The oldest population in the world  Japanese society is facing severe demographic problems such as decreasing birthrates, remaining under one million births annually recently, and a thereby aging population. The country’s average age lies at around 48 years, making its population the oldest in the world. Elderly people aged 65 years and older accounted for about 29 percent of the population in 2023. According to a forecast, the age group 65 years and older would make up approximately 39 percent of the Japanese population by 2070. Challenges with the demographic shift The rapid aging of the society poses significant economic and sociopolitical challenges to the country, as the workforce will continue to shrink while increasingly more elderly will receive long-term support. Currently, close to seven million Japanese require long-term care, leading to national benefit expenses of over 14 trillion yen annually, including in-home and community-based services.

With approximately ** million inhabitants, Tokyo Prefecture was the largest prefecture based on population size in Japan as of 2023. The smallest prefecture in this regard was Tottori Prefecture, which in the same year counted about ******* residents. Rural depopulation Like many industrial economies, Japan is facing the problem of depopulating rural areas. While the birth rate continues to decline, many young people decide to migrate from small towns and villages to large cities like Tokyo or Osaka for higher education and employment. The population of Tokyo Prefecture has shown substantial growth over the past decades and consists largely of working age citizens. Smaller communities are trying to counteract the depopulation process with initiatives meant to invite younger workers and tourists back. Migration to Japan Japan is often described as a very homogenous society, with a low share of foreign residents. Despite the declining birthrate and many businesses experiencing a labor shortage, companies have been hesitant to employ foreign workers, in part due to the strict immigration laws. The Japanese Government has tried to ease immigration restrictions and encourage foreigners to work in Japan. The largest share of foreign workers in Japan, however, is residing in the county with a permanent residence or as the family member of a Japanese national.

Text A, Representation theorem for a right eigenvector of an irreducible non-negative matrix. Text B, Theorem for infinite series expansion of characteristic equation. Text C, Original definition of type-reproduction number. Text D, Extension theorem of type-reproduction number. (ZIP)

Shrinking cities due to low birthrates and aging populations represent a significant urban planning issue. The research question of this study is: which economic, social, and educational factors affect population decline in Japanese shrinking cities? By modeling shrinking cities using the case of Japanese cities, this study aims to clarify the indicators that affect the population change rate. The study employed Bayesian network analysis, a machine learning technique, using a dataset of economic, social, and educational indicators. In conclusion, this study demonstrates that social and educational indicators affect the population decline rate. Surprisingly, the impact of educational indicators is more substantial than that of economic indicators such as the financial strength index. Considering the limitations in fiscal expenditures, increasing investment in education might help solve the problem of shrinking cities because of low birthrates and aging populations. The results provide essential insights and can function as a planning support system.

Vicia sepium (bush vetch) is a perennial legume widely distributed throughout the Eurasian continent. However, its distribution in Japan is limited to Mt. Ibuki and small parts of central and southern Hokkaido. Therefore, each Japanese V. sepium lineage has been considered to have been introduced separately from Europe. Here, we examined whether the species was introduced or not on the basis of cpDNA sequences and genome-wide SNPs from Japanese and overseas samples. Both the cpDNA haplotype network and the nuclear DNA phylogenetic tree showed that Japanese V. sepium is monophyletic. Furthermore, although the nuclear DNA phylogenetic tree also showed that each lineage is clearly monophyletic, genetic admixture of the genetic cluster dominated in the Hokkaido lineage was also detected in the Mt. Ibuki lineage. Population divergence analysis showed that the two lineages diverged during the last glacial period. The Mt. Ibuki lineage showed a sudden population decline 300–400 years ago, indicating that some anthropogenic activity might be involved, while the Hokkaido lineage showed a gradual population decline from 5,000 years ago. Consequently, these two lineages show low current genetic diversity compared with overseas lineages. These results show that the Japanese V. sepium is not introduced but is native. Methods Six SNP data sets were generated for different data analyses shown in Table 2 in the main text.

Okinotorishima Island, an isolated remote table reef island in the southernmost territory of Japan, provides an excellent site to examine the effect of only global stress, as there are no local human stresses present. Yamamoto et al. (2023) established 17 fixed quadrats (1×1 meter) on 9 knolls in the shallow lagoon of Okinotorishima Island, and observed coral population every May from 2006 to 2015. This dataset compiles data on coverage and number of colonies of Acropora and co-occurring corals published in Yamamoto et al. (2023). Yamamoto, H., Kawasaki, T., Tamura, K., Kanyama, T. Hosono, T., Fudo, M., Omori, M., Kayanne, H.: Decline in the Acropora population due to repeated moderate disturbances in Okinotorishima Island, Japan. Glaxea: Jour. Coral Reef Studies 25: 18-30 (2023). doi: 10.3755/galaxea.G26-3

Column names are based on the text and Table 1. Period IDs are as follows: 1: 1976–1987; 2: 1987–1997; 3: 1997–2006; 4: 2006–2009. (CSV)

Posterior distribution means and 95% credible intervals for the model intercept and the coefficients of predictors for each period.

Geographical and social variables explaining farmland abandonment in each period.

【リソース】Annual Report on the Environment in Japan 2006 / / Full text / Top Cover / To Our Readers / Contents / Part One: Overview / Overview 1. Population Decline and the Environment / Chapter 1. Environment in the Declining Population Era / Chapter 2. Creating a Sustainable Society Compatible with a Dwindling Population / Overview 2. Fifty Years of Minamata Disease, Origin of Japan's Environmental Problems / PartTwo Current Environmental Issues and Government Environmental Conservation Measures / Back Cover【キーワード】白書_年次報告

Nearly half of the migrant workers in the world were based in the high-income regions of Southern, Northern, and Western Europe as well as Northern America. Another 14 percent were based in Arab States. In 2019, there were around 170 million migrant workers worldwide. The American melting pot While Northern America has the second highest proportion of migrant workers globally, the United States has the highest number of migrant workers out of every country globally. In 2022, the United States had 32 million foreign-born workers. By comparison, Germany, which has the second highest number of migrant workers, had nine million foreign-born workers in 2022. Moreover, over one million people received legal permanent residence status in the United States in 2022. Japanese population crisis East Asia has a small proportion of migrant workers worldwide, at 2.8 percent of the total. Many East Asian nations have stricter barriers to migration compared to other regions. For a nation like Japan, which has a shrinking population, these policies present major challenges. In 2022, foreign nationals only accounted for 2.5 percent of Japan’s total population. In the face of an aging, decreasing population, over half of companies in Japan report shortages of full-time employees, despite Japan’s low unemployment rate.

Semi-natural grassland areas expanded worldwide several thousand years ago following an increase in anthropogenic activities. However, semi-natural grassland habitat areas have been declining in recent decades due to changes in landuse, which have caused a loss of grassland biodiversity. Reconstructing historical and recent demographic changes in semi-natural grassland species will help clarify the factors affecting their population decline. Here, we quantified past and recent demographic histories of Melitaea ambigua (Lepidoptera; Nymphalidae), an endangered grassland butterfly species in Japan. We examined changes in demography over the past 10,000 years based on 1,378 bp of mitochondrial COI gene. We then examined changes in its genetic diversity and structure during the last 30 years using nine microsatellite DNA markers. The effective population size of M. ambigua increased about 3,000 to 6,000 years ago. In contrast, the genetic diversity and effective population sizes of many populations significantly declined from the 1980s to 2010s, which is consistent with a recent decline in the species population size. Our data suggest that the M. ambigua demography can be traced to changes in area covered by semi-natural grasslands throughout the Holocene.