Effect of Tax Reform on the Size of the Hidden Economy: Evidence from the Post-Communist Natural Experiment

项目名称：税收改革对隐藏经济规模的影响：来自后共产主义自然实验的证据主张采用单一税来取代累进税的人声称，这种改革的好处之一将是大大减少经济主体通过参与隐藏或地下经济来隐藏收入的动机。 迄今为止，几乎没有证据评估这一说法的有效性。 本项目调查是否支持这一说法，利用自然实验提供的经验，在后共产主义国家的中欧和东欧的税收改革。 这项研究利用了这样一个事实，即在后共产主义世界中，每一个联邦国家近年来都分裂成一个或多个继承国，在这些继承国中，至少有一个国家实施了统一税制改革，而其他一个或多个国家保留了复杂的累进税制。 在统一税采用者（斯洛伐克，俄罗斯，塞尔维亚和格鲁吉亚）的隐性经济规模的演变进行了比较，在非采用者（捷克共和国，乌克兰（直到最近），克罗地亚和亚美尼亚）。这项研究设计提供了一个简单的，易于理解的，差异中的差异估计的影响，主要简化税收制度和降低税率的决定，以隐藏收入的当局。比较国家的存在使得能够消除许多其他因素的影响，这些因素使得任何特定改革的结果难以孤立。我们对隐性经济规模的估计是基于多种广泛使用的技术，包括实物投入（特别是电力）与国民产出的关系、流通中的货币与货币供应量的比率、对工人的直接调查，以及对家庭报告的收入与包括食品和其他商品在内的各种项目支出之间的关系的估计。直觉是，没有报告收入的家庭似乎会在购买上花费更多，而不是基于他们报告的收入。 我们使用最近开发的估计技术，使我们能够放松的假设，在以前的工作中，只有自雇户主的家庭可以隐藏收入，所有这些家庭隐藏他们的收入的相同部分。这导致对经济中未报告收入的估计更加可信。 提供多个独立的估计也使我们对税收改革对向当局隐瞒收入倾向的影响的估计具有可信度。 单一税制改革的效果是一个重要的公共政策问题。 包括美国在内的许多国家正在研究采取这种改革的可能性。 该项目的结果将为这些国家的辩论提供信息，使关于重大政策改革建议的讨论能够以比以往更可靠的经验证据为基础。

Project Title: Effect of Tax Reform on the Size of the Hidden Economy: Evidence from the Post-Communist Natural ExperimentAdvocates of the adoption of flat taxes to replace progressive taxes claim that one of the benefits of such a reform will be a substantial reduction in the incentive of economic agents to hide income by participating in the hidden or underground economy. To date there is little evidence evaluating the validity of this claim. This project investigates whether this claim is supported by taking advantage of the natural experiment provided by the experience of tax reformers in the post-communist countries of Central and Eastern Europe. The research utilizes the fact that every federated state in the post-communist world split into one or more successor states in recent years and that in each of these groups of successor states at least one country implemented a flat tax reform while one or more of the other countries retained their complex, progressive tax system. The evolution of the size of the hidden economy in the flat tax adopters (Slovakia, Russia, Serbia and Georgia) is compared with that in the non-adopters (the Czech Republic, Ukraine (until recently), Croatia and Armenia). This research design provides a simple, easily understood, difference-in-difference estimate of the impact of major simplification of tax systems and lower tax rates on the decision to hide income from authorities. The existence of the comparison counties enables the elimination of the impact of many other factors that make results from any particular reform hard to isolate. Our estimates of the size of the hidden economy are based on multiple widely-used techniques including the relationship of physical inputs (especially electricity) to national output, the ratio of currency in circulation to the money supply, direct surveys of workers, and the estimation of the relationship between households' reported income and expenditure on various items including food and other commodities. The intuition is that households with unreported income will appear to spend more on purchases then they should based on their reported income. We use recently developed estimation techniques that enable us to relax the assumptions in previous work that only households with self-employed heads can hide income, and that all such households hide the same fraction of their income. This results in more believable estimates of the amount of unreported income in the economy. The provision of multiple, independent estimates also lends credibility to our estimate of the effect of the tax reform on the propensity to hide income from authorities. The effect of a flat-tax reform is an important public policy question. Many countries, including the United States, are studying the possibility of adopting such a reform. The results of this project will inform the debate in these countries, enabling the discussion of a significant proposed policy change to be based on much more solid empirical evidence than has previously been available.