CAREER: The Evolution of Income Inequality During the 20th Century: Effects of Taxation and Policy Consequences

这项研究的总体目标是使用自本世纪初以来可获得的所得税申报单统计数据来研究四个经合组织国家：美国、加拿大、澳大利亚和新西兰收入不平等的演变。为了进行这项研究，将建立从收入分配的最高部分获得的收入份额的同质系列以及这些部分中每个部分的收入构成。所有这些国家都提供了详细的所得税统计数据，特别适合分析收入分配的顶层。这些统计数据尚未被广泛用于研究长期不平等的演变。分析的目的是评估不平等的变化是否主要是由于世界大战或宏观经济萧条和税收政策等冲击，还是由于更深层次的技术变革。这些数据还将使人们能够对税收对收入的短期和长期影响进行全面研究。利用众多的税收改革，我们计划调查每个收入来源对税收的反应，特别是长期对资本收入征收高税率是否对财富集中产生了不利影响。了解资本主义国家发展过程中不平等演变背后的机制，对于评估资本主义经济体是否具有造成不平等加剧的自然趋势，以及政府干预是否需要或是否有效地遏制不平等程度，至关重要。分析高收入者对税收的行为反应对于评估税收制度的效率和向富人征税以资助再分配计划的成本至关重要。更好地了解这些对税收的行为反应的机制，有助于改善当前的税收制度，并为低收入者提供转移支付计划。

The general objective of this research is to study the evolution of income inequality in four OECD countries: the U.S., Canada, Australia, and New-Zealand using income tax returns statistics available since the beginning of the century. To carry out this study, homogeneous series of income shares received from the top fractiles of the income distribution and the composition of income within each of these fractiles will be build. All these countries have produced detailed income tax statistics that are particularly well-suited for analyzing the top of the income distribution. These statistics have not yet been used extensively to study the evolution of inequality over the long-period. The goal of the analysis is to assess whether changes in inequality are due primarily to shocks such as world wars or macro-economic depressions and tax policy or due to deeper technological transformations. The data will also allow to do a comprehensive study of the short term, and long term effects of taxation on incomes. Exploiting the numerous tax reforms, we plan to investigate how each source of income responds to taxation, and in particular, whether the high top tax rates on capital income over long time periods have had adverse effects on the concentration of wealth. Understanding the mechanisms behind the evolution of inequality of capitalist countries over the course of their development is critical to assess whether capitalist economies have a natural tendency to create increasing inequality and whether government interventions are required or effective to curb the level of inequality. The analysis of the behavioral response of of high incomes to taxation is of central importance to assess the efficiency of the tax system and the costs of taxing the rich to finance redistributive programs. Understanding better the mechanisms of these behavioral responses to taxation can help improve current tax systems and transfer programs for lower incomes.