遺贈稅率及生前贈與——2009年及2017年兩次稅改分析

本文針對臺灣2009年及2017年的兩次遺產及贈與稅改革，分析其對生前贈與行為的影響。第一次稅改大幅調降遺產及贈與稅率，第二次則小幅提升稅率；兩次稅改所形成稅率的外生變動提供難得機會，得以克服贈與及稅制之間的內生性問題。藉由2003-2018年遺產及贈與稅核定資料，根據差異中之差異法(difference-in-differences)實證結果顯示，稅制確實影響贈與決策：2009年稅改後的實驗組生前贈與顯著增加，但在2017年稅改後卻明顯減少。比較兩次稅改對於生前贈與的影響程度則發現，在相同稅率的變動幅度下，增稅的政策效果大於減稅。

We examine the impact of estate and gift taxes on inter vivos giving in Taiwan. The two estate and gift tax reforms, one of which substantially reduced tax progressivity in 2009 while the other slightly increased tax rates in 2017, provide opportunities to perform quasi-experiments using estate and gift tax schedules to alleviate the endogeneity problem associated with these tax rates and inter vivos giving. Using estate and gift tax return data, the difference-in-differences estimators suggest that there were significant increases in inter vivos giving after the 2009 reform, but that such giving decreased after the 2017 reform. Individuals were found to be more responsive to tax hikes than tax cuts.