廢除遺贈稅是租稅競爭的策略嗎？合成控制法的應用

Is the Abolition of Inheritance Tax A Strategy of Tax Competition? An Application of Synthetic Control Method

外人直接投資是促進經濟成長的重要因素之一，因此各國政府透過各種租稅競爭策略希望吸引外人直接投資流入，本文利用合成控制法，探討在1994年至2018年間，於2000年後實施廢除遺產及贈與稅之OECD國家的外人直接投資表現進行反事實分析，進而研究廢除遺產及贈與稅對外人直接投資流入之政策效果。研究結果發現，若單純廢除遺產及贈與稅，則政策效果並無法增加外人直接投資流入之動力，若要持續吸引外資投入需有更多政策相互配合，僅實施廢除遺產及贈與稅，則需要更多時間才能反映成效或無法長期持續帶動外人直接投資流入。本研究之成果可提供欲藉由透過廢除遺產及贈與稅作為租稅競爭，以吸引外人直接投資流入之國家做為參考。

Foreign direct investment (FDI) is one of the key drivers of economic growth. Consequently, many governments adopt various tax competition strategies to attract greater inflows of FDI. This study employs the synthetic control method to conduct a counterfactual analysis of FDI performance in OECD countries that abolished inheritance (estate and gift) taxes after the year 2000, using data from 1994 to 2018. The objective is to examine the policy effect of abolishing inheritance taxes on FDI inflows. The findings suggest that merely abolishing inheritance taxes does not, by itself, generate sufficient incentives to boost FDI inflows. To sustainably attract foreign investment, such tax policy changes must be complemented by other supportive measures. Without accompanying policies, the abolition of inheritance taxes alone may require a longer time to yield observable effects, or may fail to sustain increased FDI inflows in the long term. The results of this study may serve as a reference for countries considering the abolition of estate and gift taxes as a means of engaging in tax competition to attract FDI.