Population Projections for Japan  (January 2012) 2011 to 2060
II Summary of Population Trends

The Population Projection for Japan is based on three alternative assumptions about future changes in both fertility and mortality (a low variant, a medium variant, and a high variant of each), resulting in a total of nine projections?one for each combination of these variants. Hereafter, the outline of the results of the three projections combining the three assumptions on fertility with the medium-variant assumption for mortality will be presented first, followed by an outline of the results of the three assumptions of fertility combined with the high- and low-mortality assumptions. In the following descriptions, each projection is referred to by the combination of its respective fertility and mortality assumptions, e.g. medium-fertility (medium-mortality) projection.


A. The Results of Projections According to
  the Three Fertility Variants with Medium-Mortality Assumption

1. Population Size and Growth

According to the 2010 Population Census, which serves as the base year of these projections, the total population of Japan in that year was 128.06 million (total population including non-Japanese residents). Based on the results of the medium-fertility projection, Japan is expected to enter a long period of population decline. The population is expected to decrease to around 116.62 million by 2030, fall below 100 million to 99.13 million in 2048, and drop to 86.74 million by 2060 (see Table 1-1 and Figure 1-1).

Based on the results of the high-fertility projection, the total population is expected to drop below the 100 million mark by 2054 to 99.62 million, and to decrease further to 94.60 million in 2060 (see Table 1-2 and Figure 1-1).

Conversely, based on the low-fertility projection, the total population is expected to fall below 100 million in 2044 and to decline to 79.97 million by 2060 (see Table 1-3 and Figure 1-1).

The range (difference between high and low variant) of the projected total population size by 2060 is thus equal to 14.63 million.


2. Population Age Composition

(1) Trends in the Young-age Population under 15 and its Share of the Population

 The annual number of births in Japan (Japanese) has declined from 2.09 million in 1973 to 1.07 million in 2010. Consequently, the population of children under the age of 15 (young-age population) has also decreased from 27 million in the early 1980s to 16.84 million, as recorded in the 2010 Population Census.

According to the medium-fertility projection, the population size of this age group will fall to 15 million mark in 2015 (see Table 1-1 and Figure 1-3). The decline will continue, and the population of this age group is expected to fall below 10 million in 2046, eventually decreasing to around 7.91 million by 2060.

Looking at the different trends of the number of children in the high- and low-fertility projections, this age group is expected to be on the decline even in the high-fertility projection and will reach 10.87 million in 2060 (see Table 1-2). The low-fertility projection leads to a more rapid decline in the size of this age group; it is projected that this demographic group will shrink below 10 million in 2030, and eventually decrease to as little as 5.62 million by 2060 (see Table 1-3).

Examining the declines of the young-age population in terms of percentage of the total population, according to the medium-fertility projection, the share is expected to continue to shrink from 13.1% as of 2010 to 11.0% in 2025, drop below 10% in 2044, and eventually decrease to 9.1% in 2060 (see Table 1-1 and Figure 1-4).

The high-fertility projection shows a somewhat slower decline in the percentage of children, falling below the 13% mark in 2013 and reaching 11.5% by 2060 (see Table 1-2).

The decline in the children’s share of the population is of course rapid in the low-fertility projection, breaking the 13% mark in 2012, falling below 10% in 2024, and ultimately dropping to 7.0% by 2060 (see Table 1-3).

(2) Trends in the Working-age Population (aged from 15 to 64 years) and its Share of the Population

The population of the working-age group (from 15 to 64 years of age) increased consistently during the post-war years, reaching its peak in the 1995 Population Census at 87.26 million. However, since then, it entered a period of decline and the population has fallen to 81.73 million according to the 2010 Population Census.

According to the results of the medium-fertility projection, the population of this age group is expected to continue to decrease below 80 million in 2013, below 70 million in 2027, and below 50 million in 2051, and eventually drop to 44.18 million by 2060 (see Table 1-1 and Figure 1-3).

According to the projections based on the high- and low-fertility assumptions, the working-age population trends exhibit the same overall behavior as those based on the medium-fertility assumptions until 2025. After 2025, the depopulation of this age group is expected to be slower in the high-fertility projection, not dropping below 50 million until 2058 and reaching 49.09 million by 2060 (see Table 1-2).

According to the low-fertility projection, the working-age population is expected to decrease more rapidly, falling below 50 million in 2047 and below 40 million in 2060 to 39.71 million (see Table 1-3).

Looking at the proportion of the population in the working age group, according to the medium-fertility projection, it is seen that the proportion will continue to fall from its 2010 share of 63.8%, declining to below 60.0% in 2017, reaching 53.9% (approximately ten percentage points lower than the current level) in 2040, and eventually declining to 50.9% by 2060 (see Table 1-1 and Figure 1-4).

In the high-fertility projection as well, the population share of the working-age group shows a constant decline from the start of the projection period, reaching 51.9% in 2060, just 1 percentage point higher than the result of the medium-fertility projection.

In the low-fertility projection, the proportion of this age group out of the overall population will decline relatively slowly for a certain period of time, primarily due to a sharp decline in the number of children. Therefore, the timing of the percentage falling to 60.0% will be in 2018, one year later than in the projection based on medium-fertility assumptions. However, the subsequent decline will then accelerate, and the population share will reach 49.7% in 2060, 1.2 percentage points lower than the projection based on medium-fertility assumptions.

(3) Trends in the Old-age Population (65 years of age and over) and its Share of the Population

The trends exhibited by the old-age population (65 years of age and over) will be identical for all three fertility variant assumptions throughout the projection period of 50 years if the assumption on mortality is the same. That is, this age group will grow from 29.48 million as of 2010 to over 30 million in 2012 when the baby-boom generation (born between 1947 and 1949) enters this group, and to 36.12 million by 2020 (see Table 1-1, Table 1-2, Table 1-3, and Figure 1-3). It will then enter a period of modest increase for some time, reaching 37.01 million in 2033, and will peak in 2042, reaching the 38.78 million in 2042 when the second baby-boom cohorts enter this age group. The trend will shift to a steady decrease afterward, and the size of the age group will ultimately reach 34.64 million by 2060.

Looking at the proportion of elderly out of the entire population, the share will increase from the current level of 23.0% as of 2010 to 25.1 to 25.2% in 2013, meaning that more than one in four people in Japan will be elderly, according to all the projections based on the three-fertility assumptions. Later on, by 2035, 33.4% of the total population, corresponding to one in three people, will be elderly, and 50 years after the start of projection period, in 2060, the elderly will account for no less than 39.9%, i.e., one in 2.5 people, according to the medium-fertility projection (see Table 1-1 and Figure 1-2).

The results of the high-fertility projections shows that the share will be 33.3%, i.e., one in three people, in 2037 and 36.6% in 2060, i.e., one in 2.7 people will be elderly (see Table 1-2 and Figure 1-2).
In the low-fertility projections, the share will be 33.3%, i.e., one in three people, in 2033 and 43.3% in 2060, i.e., one in 2.3 people will be elderly (see Table 1-3 and Figure 1-2).

A comparison of the results of the high- and low-fertility projections shows that the variation in the aging trend brought about by different assumptions of fertility rate amounts to a difference of 1.4 percentage points in 2030, from 32.3% in the low-fertility projection to 30.9% in the high-fertility projection. This difference grows wider thereafter, resulting in a difference of 6.7 percentage points 2060, where the low-fertility figure is 43.3% as opposed to the high-fertility figure at 36.6% (Figure 1-2).

As already noted, the growth rate of the elderly population itself will decelerate from around 2020, and the population will peak at 2042 and decrease thereafter. Nevertheless, the proportion of the elderly generation will continue to rise throughout the coming 50 years, according to both the medium- and low-fertility assumptions. This happens essentially because the child and working-age populations decrease faster throughout the period covered by the projections than the elderly age group.


3. Age Dependency Ratios

The (Total) age dependency ratio is an index that gives a rough indication of the level of support burden placed on the working-age group, through comparison of the relative size of the young-age population and old-age population groups with that of the working-age group. The old-age dependency ratio (the percentage of the old-age population relative to the population of the working-age group) based on the medium-fertility projection is projected to increase from 36.1 (that is, 2.8 workers supporting one senior resident on average) as of 2010 to 50.2 (two workers supporting one senior resident) by 2022, and eventually reach 78.4 (only 1.3 workers supporting one senior resident) by 2060 (see Table 1-4). In contrast, the young-age dependency ratio (the percentage of the young-age population relative to the population of the working-age group) was at the level of 20.6 (that is, 4.9 workers supporting one child on average) as of 2010, and will remain in the range of 17 to 20 in the future. Despite the decrease in the young-age population due to low fertility, the young-age dependency ratio is not expected to decrease below a certain level from around 2029, because the working-age population will also simultaneously shrink in size.

The value obtained by adding the young-age dependency ratio and the old-age dependency ratio is referred to as the total age dependency ratio, and is used to indicate the degree of burden placed on the working-age population to support the entire young-age/old-age population. According to the medium-fertility projection, the total age dependency ratio is expected to increase from 56.7 as of 2010 to 80.0 in 2037, and will eventually reach 96.3 by 2060, under the shrinking working-age population.

The age dependency ratio based on the high-fertility projection will initially follow a trend that is higher than that of the medium-fertility projection, because the young-age dependency ratio will be larger. However, the ratio on the high-fertility projection decreases below that of the medium-fertility projection in 2044 and beyond, and is expected to reach 92.7 by 2060. In contrast, the age dependency ratio based on the low-fertility projection will initially maintain a lower level than the projections based on the medium-fertility projection, but the relationship will eventually reverse in 2043, and will reach 101.4 by 2060.


4. Changes in the Population Pyramid

The population pyramid in Japan has significant irregularities due to acute fluctuations in past numbers of live births. For example, there was a decrease in the number of live births from 1945 to 1946 in line with the termination of the World War II, an increase known as the first baby boom from 1947 to 1949, a subsequent decrease from 1950 to 1957, and a sharp single-year drop in 1966, which corresponded to a period in the Chinese sexagenary cycle that, owing to traditional beliefs, is accompanied by a sharp decline in birthrates. This was followed by a subsequent increase referred to as the second baby boom cohorts from 1971 to 1974, and a steady decrease thereafter (see Figure 1-5(1)).

In the population pyramid as of 2010, the members of first baby-boomer generation are in their early 60s and those of the second baby-boomer generation are in their late 30s. Looking at the subsequent evolution of this pyramid shape according to the medium-fertility projection, the first baby-boomers will be in their early 80s and the second baby-boomers will be in their late 50s in 2030. It can therefore be concluded that the aging of the society toward 2030 is characterized by the entry of the first baby-boomer generation into the aged population (see Figure 1-5(2)).

The advancement of the aging society thereafter until 2060 will reflect the fact that the second baby boomer generation will enter the aged population as well as fact that the population size of the younger generations of all age brackets will decrease due to the low fertility (see Figure 1-5 (3)).


B. The Results of Projections According to the Medium-Fertility
  Assumption with High- and Low-Mortality Assumptions

1. Summary of the Results of Projection with High-Mortality Assumption

The high-mortality projection assumes higher mortality rates compared to the medium-mortality projection, which means slower advance in mortality improvement, and an overall life expectancy that remains at a relatively lower level. Therefore, under the same assumptions on fertility, the number of deaths will maintain a larger level and the population will maintain a lower level than in the medium-mortality projection throughout the projection period. That is, compared to the total population estimate of 86.74 million in 2060 based on the medium-fertility (medium-mortality) projection, the total population in the same year based on the medium-fertility (high-mortality) projection drops down to 85.32 million. In contrast, the population and the demographics of the three major age groups based on the medium-fertility (high-mortality) projection are as follows: in 2060, the child population (and the proportion thereof) will be 7.90 million (9.3%), the working-age population (and the proportion thereof) will be 44.10 million (51.7%), and the elderly population (and the proportion thereof) will be 33.32 million (39.1%), all of which are lower than the results of the medium-fertility (medium-mortality) projection, and the size and proportion of the elderly population, in particular, are smaller (see Table 2-1 and Table 3-4).

2. Summary of the Results of Projection with Low-Mortality Assumption

The low-mortality projection assumes a lower mortality rate as compared with the medium-mortality projection, which means a faster advance in mortality improvement, and a life expectancy that remains at a relatively high level. In this case, the number of deaths will be relatively small, and the population will maintain a higher level under the same fertility assumptions. That is, compared to the total population as of 2060 based on the medium-fertility (medium-mortality) projection, 86.74 million, the total population in the same year based on the medium-fertility (low-mortality) projection will be 88.15 million. On the other hand, the trends of the size and proportion of the three major age groups based on the medium-fertility (low-mortality) projection can be summed up as follows: in 2060, the child population (and the proportion thereof) will be 7.92 million (9.0%), the working-age population (and the proportion thereof) will be 44.26 million (50.2%), and the elderly population (and the proportion thereof) will be 35.97 million (40.8%), all of which are higher than the results of the medium-fertility (medium-mortality) projection, and the size and proportion of the elderly population, in particular, are larger (see Table 2-2 and Table 3-4).


C. The Results of Projections According to
  the High- and Low-Fertility Assumptions with High- and
  Low-Mortality Assumptions*

In the Population Projections for Japan, we made four additional possible projections combining the high- and low-fertility assumptions and the high- and low-mortality assumption, respectively, in addition to the aforementioned projections. According to the high-fertility (low-mortality) projection, which results in the highest total population, the total population may potentially be as high as 96.02 million in 2060. In contrast, in the low-fertility (high-mortality) projection, which results in the lowest total population, the total population may end up as low as 78.56 million in the same year (Table 3-1). Moreover, the proportion of the elderly population is 44.2% in 2060 according to the low-fertility (low-mortality) projection, which results in the highest proportion of the elderly population, while the same proportion is 35.8% in the same year according to the high-fertility (high-mortality) projection, which results in the lowest proportion of the elderly population (Table 3-4).

* The tables showing the main results of these projections are not included in this outline report. Please refer to the Website of the National Institute of Population and Social Security Research in Japan for these tables.。


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