The line graph indicates how the Japanese population changed by different age groups from 1960 to 2040.

Overall, the percentages of people aged 0-14 and 15-64 witness downward trends over the 80 years, while the proportion of those who are 65 and over experience an opposite trend.

In 1960, the proportion of people aged 15-64 started at about 65%, followed by a slight fluctuation during the next 30 years before falling to around 58% in 2020. This figure is projected to experience a fall at about 52% by 2030, finally coming back to around 55% of the total population in 2040. The figures for those aged 0-14 showed a similar pattern, beginning at 30% in 1960 and increasing by 5% in 1970. This figure is estimated to drop to about 10% by 2040.

In contrast, the percentage of over 65 age people accounted for only 5% in 1960. Following that, the figure witnessed a significant increase to 30% in 2020, and it is forecast that approximately 35% of Japan's population will fall into this age group by 2040.