A Study on the Impact of Social Security Contribution on the Saving Ratio

首先，利用本项目的宏观经济数据进行回归分析，发现社会保障制度的进步总体上对储蓄有负面影响。使用协整分析的另一项分析发现，社会保障基金中的储蓄取代了家庭储蓄。基于考虑流动性约束和风险因素的欧拉方程的分析表明，退休后生活的不确定性增加了储蓄。其次，从Kakei-Keizai研究所的调查中收集的面板数据显示，年轻一代保持比年长一代更贫穷的趋势。根据我们对再分配政策的分析，在人口老龄化的情况下，社保基金持有一定的基金存量是有意义的。公共养老金作为动态人口冲击的缓冲资金的提取可能会导致代际不平等。20世纪90年代收入差距的扩大可以很大程度上归因于人口老龄化，尽管年轻一代的不平等也在加剧。我们还发现，在代际再分配的情况下，家庭部门承担的贡献(负担)(社保缴费和纳税的总和)的再分配效应大于代内再分配的情况。最后，我们考察了日本失业者的不储蓄行为，发现失业者没有显著地提取储蓄。

Firstly, a regression analysis using macroeconomic data in this project found out that the progress of the social security system in general have a negative impact on saving. A separate analysis using cointegration found that the saving in the social security fund substitute household savings. An analysis based on the Euler equation with the liquidity constraint and risk factors showed that the uncertainty about the life after the retirement increases saving.Secondly, the panel data collected from a survey of Kakei-keizai Research Institute showed an increasing tendency of the younger generation remaining poorer than its senior generations. It was also found that the income inequality tended to remain and enlarge.According to our analysis concerning redistribution policies, it is meaningful for the social security fund to hold a certain stock of fund under the aging population. The drawing down of the accumulated fund for the public pension as a buffer for the dynamic demographic shock may lead to the intergenerational inequity.The widening of the income gap in the 1990s can be significantly attributed to the aging of the population, although the inequality in the young generation is also intensifying. We also found that the redistributional effect of the contribution (burden) born by the household sector (the sum of social security contribution and tax payment) is larger in the case of inter-generational redistribution than in the case of intra-generational redistribution.Lastly, we examined the dissaving behavior of the unemployed in Japan finding that those unemployed to not withdraw their saving significantly.