全面变革与不确定的遗产：2017年《减税与就业法案》

中文摘要

2017年《减税与就业法案》（TCJA）对个人和企业税收进行了全面改革。我们概述其主要条款，追溯该法案的起源，并将其与以往的税制改革进行比较。我们还考察了其对政府预算、经济活动和资源分配的影响。基于截至2019年的证据，我们发现TCJA明显增加了联邦债务并提高了税后收入，且不成比例地增加了最富裕群体的收入。其对GDP和工资中位数的影响充其量似乎是温和的，尽管难以确定明确的反事实情形。其对投资的影响则更不确定，针对这一问题的研究直到最近才开始出现。由于2020年开始的新冠疫情造成的干扰，对其更长期影响的实证分析可能会十分困难。

Abstract

The Tax Cuts and Jobs Act (TCJA) of 2017 introduced sweeping changes to individual and corporate taxation. We summarize the major provisions, trace the origins of the Act, and compare it to previous tax changes. We also examine the effects on the government budget, economic activity, and distribution of resources. Based on evidence through 2019, we find that the TCJA clearly raised federal debt and increased after-tax incomes, disproportionately increasing incomes for the most affluent. Its effects on GDP and median wages seem modest at best, although clear counterfactuals are difficult to identify. The impact on investment is less certain, and research is only recently emerging that addresses this question. Empirical analysis of longer-term effects may prove difficult due to the disruptions created by the COVID-19 pandemic starting in 2020.