中国人口年龄结构与养老保险制度的福利效应

预测表明，中国人口老龄化程度则在2005年以后不断增加；与此同时，在2030年以前城镇有效劳动力数量不断增加，随后会下降。在此背景下中国的养老保险制度应该在多大程度上发挥再分配的功能是养老保险制度改革需要确定的一个原则。采用中国的参数．评价养老保险制度的福利效应是本文的主要目的。养老保险的福利效应对不同时期出生的人有所差异，如果政府的目标函数兼顾效率和公平。可以得到一个对于社会总福利而言最优的养老保险规模。我们的模拟表明一个合适的现收现付制的养老保险制度在中国可以改进社会总福利。

Demographic Structure and the Welfare Effect of Pension System in China

According to the demographic prospect, population aging will be increasing after year 2005. Meanwhile the effective urban labor force keeps growing until 2030. Therefore, the reform of Chinese pension system should be based on the change of demographic structure to determine to what extent the pension system plays a role on redistribution. We evaluate the welfare effect of pension system by employing Chinese data. The simulation shows that a certain size of pay-as-you-go pension is necessary to maximize the social welfare if the government considers both efficiency and equity.