The results can be summarized as follows. The results can be summarized as follows: in Japan, the demographic characteristics are the continuous decline of birth rate and the extension of life expectancy, which leads to the aging of the population. The sharp decline in fertility rate is also the reason for the significant decline in Japan's population. In Japan, demographic data can be defined as the continuous decline of birth rate and the increase of life expectancy, leading to an aging population. The sharp decline of fertility rate is also the reason for the obvious decline of Japanese population. As a result of the contraction of the labor force, the real GDP level is expected to drop by about 20% in the next half century or so (starting from the baseline of the constant labor force). As a result of contract workers, the real GDP level is expected to drop by about 20% in the next half century or so. As far as growth is concerned, the annual growth rate of Japan's GDP may be lower than about 0.5% for some time, because the economy will reach a long-term equilibrium and be permanently higher than the long-term equilibrium. As far as growth is concerned, the annual growth rate of Japan's GDP will be lower than about 0.5% for a long time, because its economy is stable in a long-term equilibrium state, accompanied by a long-term high old-age dependency ratio and less labor supply.

In terms of per capita, in the long run, the per capita GDP has slightly decreased (relative to the baseline level). ) The promotion of labor contracts leads to a decline in output-measured by efficiency units. In everyone's sense, per capita GDP will decline slightly in the long run (relative to the benchmark), and output will decline in proportion to the labor contraction measured by efficiency units. However, with the increase of the proportion of the elderly population, the percentage of effective labor supply decreased more than that of the (adult) population. In the process of adjustment, the level of investment and savings also decreased with GDP. However, due to the share of the elderly, the percentage of effective labor supply has decreased more than that of the (adult) population. Through this adjustment process, the level of investment and savings will also decline with the decline of GDP. The decline in investment reflects the desire to get rid of capital by keeping the investment rate (the proportion of GDP) unchanged after the contraction of labor force and output. The decline in investment reflects the desire for capital outflow due to the contraction of labor force and output, although the investment ratio (as a part of GDP) remains unchanged. In any case, with the aging of the population, the savings rate and current account ratio will increase slightly. However, with the increase of population age, the savings rate and current account ratio will increase slightly. Although the proportion of the elderly is higher (they tend to save less), the increase in life expectancy and the decrease in the inflow of young agents (who tend to have a high propensity to consume) have increased Japan's savings rate. Although the proportion of the elderly (who tend to save less) is high, the extension of life expectancy and the decrease of young brokers (who tend to spend more) will help to increase Japan's savings rate.

As far as policy impact is concerned, the analysis emphasizes the importance of considering the expected changes in the macroeconomic environment when evaluating policies to meet the challenges of population aging. From the perspective of the relationship between policies, the analysis emphasizes the importance of considering the future changes of macroeconomic environment when evaluating policies to meet the challenges brought by population aging. If we only pay attention to the social security level and ignore the impact of demographic changes in fiscal accounts on the macro-economy, then this analysis misses an important part. For example, if the financial sustainability assessment that only focuses on social security ignores the macroeconomic relationship of population changes in financial accounts, then an important part of the analysis will be ignored. Similarly, when examining policy reform, we should also consider the endogenous response of private behavior to different policy changes. Similarly, when discussing policy reform, we should also consider the endogenous response to various private policies. On the last point, the simulation analysis shows that the change of social security benefits will have an indelible impact on private sector savings. On the last point, the simulation analysis shows that the change of social security benefits will have a great impact on private deposits. In particular, the decline in the balance between welfare and contribution rate shows that nearly half of the decline in welfare rate will boost the private savings rate, because agents avoid having to raise more consumption funds themselves when they retire. In particular, the decline in the balance between profit and contribution rate has been proved to increase the private savings rate, which is close to half of the decline in profit rate, because brokers expect that people will have to raise more funds themselves for retirement consumption.