Okayama岡山県
Setouchi 瀬戸内市
Data last updated:
Setouchi, Okayama, Japan has a population of 34,654 (2025 national census). IPSS projections estimate 33,200 by 2030 and 26,719 by 2050 (a decrease of about 25.9% from 2020), with the share of residents aged 65+ rising from 34.6% in 2020 to 43.2%.Sources: Japan Census (Statistics Bureau), IPSS Regional Population Projections (2023)
2025Census
34,654
2030Projection
33,200
▼ -7.9%
2040Projection
29,991
▼ -16.8%
2050Projection
26,719
▼ -25.9%
Change vs. 2020 census
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Other municipalities in Okayama (岡山県)
Data Sources
- Portal Site of Official Statistics of Japan (e-Stat)（https://www.e-stat.go.jp/）
- National Institute of Population and Social Security Research (IPSS), Regional Population Projections (2023 ed.)
* This service uses the e-Stat API but its content is not guaranteed by the Japanese government.
Setouchi Population Table (1980–2050)
Population by year: national census results (restated to current municipal boundaries) and IPSS (2023) projections based on the 2020 census.
| Year | Population | vs 2020 | Type |
|---|---|---|---|
| 1980 | 37,939 | ▲ +5.2% | Census |
| 1985 | 38,838 | ▲ +7.7% | Census |
| 1990 | 38,928 | ▲ +8.0% | Census |
| 1995 | 39,228 | ▲ +8.8% | Census |
| 2000 | 39,403 | ▲ +9.3% | Census |
| 2005 | 39,081 | ▲ +8.4% | Census |
| 2010 | 37,852 | ▲ +5.0% | Census |
| 2015 | 36,975 | ▲ +2.6% | Census |
| 2020 | 36,048 | — | Census |
| 2025 | 34,654 | ▼ -3.9% | Census |
| 2030 | 33,200 | ▼ -7.9% | Projection |
| 2035 | 31,660 | ▼ -12.2% | Projection |
| 2040 | 29,991 | ▼ -16.8% | Projection |
| 2045 | 28,338 | ▼ -21.4% | Projection |
| 2050 | 26,719 | ▼ -25.9% | Projection |
About Setouchi
Overview
Setouchi (瀬戸内市) is a municipality in Okayama, Japan, with a population of 34,654 as of 2025.
Population Projection of Setouchi
According to projections by Japan's National Institute of Population and Social Security Research (IPSS), Setouchi's population is expected to reach 33,200 by 2030 (-7.9%), 29,991 by 2040 (-16.8%), and 26,719 by 2050 (-25.9%). A significant population decline is projected over the next three decades.
Aging Rate of Setouchi
The aging rate (percentage of residents aged 65 and over) is 34.6% as of 2020 and is projected to rise to 43.2% by 2050. Over 40% of residents will be elderly, significantly affecting healthcare and social services needs.
National Comparison
Setouchi's population decline rate exceeds the national average.
National and Prefectural Rank
- Population decline rate: Ranked #1182 out of 1903 municipalities nationwide.
- Aging rate in 2050: Ranked #1009 out of 1903 nationwide.
- Population size: Ranked #840 out of 1917 nationwide.
- Related: National rankings / All municipalities in Okayama
Earnings in Okayama (岡山県): Average salary in Okayama (岡山県) by age, gender and company sizejpsalary / MHLW Basic Survey on Wage Structure