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

首先，本项目利用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产生负面影响。另一项使用协整的分析发现，社会保障基金的储蓄替代了家庭储蓄。根据考虑流动性约束和风险因素的欧拉方程进行的分析表明，退休后生活的不确定性增加了储蓄。第二，从调查收集的面板数据来看，年轻一代比年长一代更穷的趋势越来越明显。通过对再分配政策的分析，认为在人口老龄化的背景下，社会保障基金保持一定的资金存量是有意义的。作为人口动态冲击缓冲器的公共养老金积累基金的提取可能导致代际不公平，20世纪90年代收入差距的扩大可以显著归因于人口老龄化，尽管年轻一代的不平等也在加剧。另外，在代际再分配的情况下，家庭部门承担的贡献（负担）（社会保障和税收的总和）的再分配效果比代际内再分配的效果更大。最后，我们对日本失业者的储蓄支出行为进行了分析，发现失业者的储蓄支出并不显著。

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.