中国企业税费负担水平和差距：现状、原因及影响

减税降费是近十年中国财税政策的主旋律。哪种减税降费的方式最优呢？学界还没有系统科学的解答。本课题通过研究企业税费负担分布的现状、来源及影响来解析这个难题。我们首先系统描述企业的税费负担水平及不平等的历史和现状，并进行国际比较。我们考虑社保和补贴，并考察税费负担的转嫁。接着我们分析企业税费负担不平等的来源，分解各税种的贡献，组间和组内差距的贡献，企业特征的贡献，区分政策优惠和征管或避税的贡献；并研究税负分布如何受经济周期，政府激励约束，信息化和新经济，及重大税费政策影响。第三块分析税费负担差距如何影响企业、工人和经济，包括对企业投资创新避税行为、企业绩效、资源配置效率、产业结构、就业和收入分配，及经济发展的影响。我们利用税费政策变动带来的外生性税负差距变化来识别因果关系。第四块评估近十年四个重大税费政策。最后我们尝试结构模型估计，为最优减税降费政策和下一步税费政策改革提供建议。

Tax cut is the major theme for Chinese tax policies in the last decade. However, what is the optimal structure of a tax cut? Researchers have not provided a comprehensive and scientific answer. Our project explores the question by investigating the level and the inequality (dispersion, heterogeneity) of firm tax-fee burden, the reasons behind it, and the effects of it. We first systematically describe the status and trend of the burden level and inequality, and use international comparison to understand whether the burden is too high. We examine social security fees and government subsidy. The tax incidences of different taxes are examined. Then we examine the source of the tax-fee inequality, by decomposing the contributions of different types of taxes, of within-group and between-group, of firm characteristics, and of preferential tax. We also examine how the tax-fee inequality is affected by business cycles, government incentives, informationalized enforcement and new economy, and important tax policies. Next, we analyze how the tax-fee inequality affects firms, workers, and the economy, including firm investment, innovation, and tax avoidance, firm performance, labor market and income inequality, resource allocation efficiency, and economic growth. We exploit the exogenous change in inequality due to tax policy changes.The fourth part of the project evaluates four important tax policies in the recent decade. Finally, we try structural estimation and do welfare analysis. We provide suggestions on optimal structure of tax cut and the direction for the next round of tax reforms.