【Aging, safety net and fiscal crisis in Japan】No.105: Projection of the Elderly Population by Prefecture

As explained in column number 101, according to the population projection (April 2017) released by the National Institute of Population and Social Security Research, Japan's population is estimated to decrease by 16.3%, from 127,095,000 in 2015 to 106,421,000 in 2045. However, the population aged 65 and older will increase by 15.7%, from 33,868,000 to 39,192,000 during the same period. By analyzing this projection and dividing it into two age groups, ages 65 to 74 and age 75 and over, the problem of Japan's accelerating aging will become clearer.

As shown in Table 1, the population aged 65 to 74 will decrease from 17,546,000 in 2015 to 16,426,000 in 2045. The population aged 75 and over will increase by 6,445,000, from 16,322,000 to 22,767,000 during the same period. The increase in population over the age of 75 in the South Kanto area, which consists of Tokyo, Kanagawa, Saitama, and Chiba, accounts for 38% of the increase in population over the age of 75. The increase in population over the age of 75 in eight prefectures, including Osaka, Aichi, Hokkaido, and Fukuoka, accounts for 61% of it (Figure 1). In other words, the increase in elderly people over the age of 75, whose medical/long-term care expenses per capita and dementia risks are high, is concentrated in metropolitan areas.

While there are 12 prefectures whose population of elderly people over the age of 65 will decrease from 2015 to 2045, their population of elderly people over the age of 75 is also expected to increase from 2,149,000 in 2015 to 2,379,000 in 2045. On the other hand, the population under the age of 64 is estimated to decrease significantly. As a result, in these 12 prefectures, the percentage of elderly people over the age of 75 will reach 25.7% in 2045. In the case of Akita, where the population declines the most, the ratio is 31.9% (Table 2).

Table 1: Elderly population by prefecture (thousand)

Table 2: Percentage of elderly population by prefecture

Figure 1: Prefectures where the increase of the elderly population over the age of 75 is large