Social Security Growth Versus Income Tax Reform: An Analysis of Progressivity and Horizontal Equity in the Federal Tax System in the 1980s.
利用IRS和密歇根大学面板数据，模拟1980年代税法变化对所得税与社会保障税合并分布的累进性和横向公平影响，发现社会保障税增长抵消了所得税改革的累进效果。
Abstract The substantial reductions in individual income tax rates that have characterized the 1980s have been accompanied by continued growth in the social security tax. In this study, data from the IRS Individual Tax Model File and the Arthur Young/University of Michigan Taxpayer Panel is used to simulate the effects of tax law changes in this decade on progressivity and horizontal equity in the combined distribution of income and social security taxes. The results suggest that the regressive effects of increases in the social security tax have dominated the progressive effects of individual income tax reform during this decade. With regard to horizontal equity, the results indicate that social security tax growth has contributed to the general increase in horizontal equity resulting from the Tax Reform Act of 1986.