The Tax Complexity Index – A Survey-Based Country Measure of Tax Code and Framework Complexity
构建了税收复杂性指数（TCI），通过调查大型国际税务服务网络的高经验税务顾问，衡量100个国家的企业所得税系统复杂性，发现各国及国内税法和框架复杂性差异显著，且与GDP等国家特征存在不同关联。
This paper introduces the Tax Complexity Index (TCI). The TCI comprehensively measures the complexity of countries’ corporate income tax systems faced by multinational corporations. It builds on surveys of highly experienced tax consultants of the largest international tax services networks. The TCI is composed of a tax code subindex covering tax regulations and a tax framework subindex covering tax processes and features. For a sample of 100 countries, we find that tax complexity varies considerably across countries, and tax code and framework complexity also vary within countries. Among others, tax complexity is strongly driven by the complexity of transfer pricing regulations in the tax code and tax audits in the tax framework. When analyzing the associations with other country characteristics, we identify different patterns. For example, we find a positive association of GDP with tax code complexity and a negative association with tax framework complexity, suggesting that highly economically developed countries tend to have more complex tax codes and less complex frameworks. Overall, the tax complexity measures can serve as valuable proxies in future research and supportive tools for a variety of firm decisions and national and international tax policy discussions.