中国养老保险体系改革的福利经济学分析

本文用一个福利经济学框架推导出在社会福利最大化目标下现收现付制和基金制混合的养老保险体系的最优混合比率 ,模型中考虑了收入分配的因素 ,模型对过往研究中已有的结论进行了扩展 ,显示当一国的工资增长率和人口增长率之和大于投资报酬率 ,或者 ,当收入差距较大时 ,采用现收现付制有益于整个社会福利的改善。用这一框架分析中国的养老保险体系 ,并结合中国养老保险体系改革的特点 ,得出的结论是在当前及今后相当长的时间内 ,以现收现付制为主的体系可以作为中国养老保险体系的选择。文章进一步分析了现收现付制在中国持续运行的空间及其面临的挑战 ,指出这一制度的可持续运行最终取决于劳动生产率和产出的水平及增长

Welfare Analysis of China's Pension Reform

A standard model is used to show that when incomes are unequal and the product of the rates of growth of wages and of the population are in excess of the rate of interest, a PAYG system is in the interests of the society as a whole. A formula is derived for the optimal share of the two pillars. It is argued that the problems of the Chinese pension system are not caused by the use of PAYG but by the particular parameter values, notably incomplete contributions coverage, low pension ages, and a high replacement rate. It is these factors, and the rate of growth of output, which determine the viability of the Chinese pension system.