中文摘要
随着财政赤字上升以及公众对富人避税问题的关切增强，我们研究了未实现收益与借贷如何影响美国人的所得税。我们有四项主要发现：第一，将“经济收入”测度为现行应税收入加上新增未实现收益，所得税税基能够涵盖财富前1%人群经济收入的60%（经通胀调整后为71%），对较低财富群体则能涵盖其绝大部分收入。第二，对未实现收益进行调整后，所得税的累进程度显著降低，尽管其总体上仍保持累进。第三，我们首次量化了整个财富分布中的借贷规模。聚焦于前1%人群，尽管总借贷规模可观，但每年新增借贷相较于其新增未实现收益而言相当小（占经济收入的1%–2%），这表明“买入、借贷、死亡”并非富人的主导性避税策略。第四，富裕美国人的消费低于其流动收入，部分原因在于富人拥有大量流动收入，部分原因在于其储蓄率较高，这表明超级富豪的主要避税策略是“买入、储蓄、死亡”。
Abstract
As deficits rise and concerns about tax avoidance by the rich increase, we study how unrealized gains and borrowing affect Americans’ income taxes. We have four main findings: First, measuring “economic income” as currently-taxed income plus new unrealized gains, the income tax base captures 60 % of economic income of the top 1 % of wealth-holders (and 71 % adjusting for inflation) and the vast majority of income for lower wealth groups. Second, adjusting for unrealized gains substantially lessens the degree of progressivity in the income tax, although it remains largely progressive. Third, we quantify for the first time the amount of borrowing across the full wealth distribution. Focusing on the top 1 %, while total borrowing is substantial, new borrowing each year is fairly small (1–2 % of economic income) compared to their new unrealized gains, suggesting that “buy, borrow, die” is not a dominant tax avoidance strategy for the rich. Fourth, consumption is less than liquid income for rich Americans, partly because the rich have a large amount of liquid income, and partly because their savings rates are high, suggesting that the main tax avoidance strategy of the super-rich is “buy, save, die.”