The population in all of Japan's 47 prefectures except Tokyo is projected to fall in 2050 from 2020 levels, a government estimate showed Friday.

Eleven prefectures will each see their population shrink by over 30 percent, while the number of residents in some 20 percent of all municipalities is expected to more than halve, according to the National Institute of Population and Social Security Research.

Japan's population is expected to fall 17 percent during the same period to 104.69 million, the research body of the health ministry also said.

File photo taken from a Kyodo News helicopter in December 2022 shows the National Stadium and skyscrapers in central Tokyo. (Kyodo)

With regions experiencing significant population decline likely to face difficulties in maintaining infrastructure and local governments due to reduced tax revenue and economic contraction, addressing the declining birthrate and influx to Tokyo has become a matter of urgency.

Prefectures in northeastern Japan are projected to see the sharpest population declines, with Akita expected to experience a 41.6 percent drop to 560,000. Aomori and Iwate are projected to shrink 39.0 percent and 35.3 percent, respectively.

Meanwhile, Okinawa is expected to see the slowest pace of decline at 5.2 percent, followed by Tokyo's three surrounding prefectures -- Kanagawa, Chiba and Saitama -- at 7.7 percent, 9.5 percent and 9.7 percent, respectively.

Tokyo is the only prefecture whose population is projected to grow from 2020, increasing 2.5 percent to 14.40 million.

Those aged 14 and under are expected to fall 30.8 percent nationwide, while 25 prefectures are forecast to have people aged 65 and above account for over 40 percent of their population by 2050.

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