Social Security and Individual Welfare: Precautionary Saving, Borrowing Constraints, and the Payroll Tax
研究在资本市场不完善（私人年金市场缺失和借贷限制）下，社会保障对国民储蓄和个人福利的影响，发现借贷约束会削弱甚至消除福利改善，提示需重新审视比例工资税融资方式。
This paper examines the impact of social security on national saving and individual welfare in the presence of realistic capital-market imperfections: market failure in the private provision of annuities and restrictions on borrowing against anticipated future wages. The introduction of social security increases lifetime welfare and reduces national saving if borrowing restrictions are absent. However, the increase in individual welfare is reduced, and in some cases eliminated, when borrowing constraints are taken into consideration. The substantial difference suggests the importance of reexamining the proportional payroll tax finance of social security. Copyright 1987 by American Economic Association.