財富流動性與遺產稅

過往文獻聚焦於分配不均 (inequality) 的討論，然而經濟資源在代際之間流動性 (mobility) 的研究則相對有限，尤其財富的文獻更是稀少。由於財富相較於所得更能反映個人的經濟狀況，且更集中於少數人所擁有，因此財富流動性的討論有助於充分瞭解分配的態樣、勾勒社會的公平樣貌，並提供政府重分配政策設計的參考。本文分別探討以下議題：一、以2001年至2018年臺灣遺產稅核定資料串聯父母與子女的財富資料，實證結果指出，相較於其他國家，臺灣的財富流動性程度較高。然而進一步分析不同財富分位的流動性，發現高財富階層的財富僵固程度明顯高於貧窮階層，隱含高財富家庭得以在代際更迭之間持續維持高財富地位。二、檢視父母的財富配置、地區的異質性與遺產稅對於財富流動性的影響。首先以父母的財富配置而言，父母將自身的資產配置知識、偏好、風格傳承予子女，使得兩代之間的儲蓄與財富組成決策相似，進一步導致父母與子女之間的財富有所關聯。為了驗證此一說法，本文估計金融資產與不動產的代際彈性，發現金融資產的代際彈性高於不動產，顯示金融資產在代際之間的僵固性較高；此外，父母將越多財富配置於金融資產，子女財富地位提升的程度越高，反映隨著我國經濟發展以及金融市場的成長，個人的財富累積方式逐漸從不動產移至金融資產。再者，以地區的異質性而言，實證結果發現戶籍縣市為直轄市的子女，其財富規模高於父母的機率更高，且與父母財富地位的差異提升，隱含城鄉差距對於財富累積的影響係橫跨多個世代的。最後，本文以2009年遺產稅稅改所提供遺產稅租稅負擔的外生變動，分析遺產稅對於財富流動性的影響，以租稅負擔受稅改影響的被繼承人為實驗組，差異中的差異模型 (difference-in-differences, DID) 實證結果指出，2009年遺產稅降稅使得代際彈性顯著提升、財富流動性下降。三、本文以2009年遺產稅的降稅分析遺產稅負與租稅規避之間的關聯，DID的估計結果指出，以農用農地、公設地及債務等三個遺產稅租稅規避常用的工具而言，其金額與財富占比均於稅改後顯著減少。其中，農用農地與公設地的減少並非反映被繼承人實質投資決策的變化，而是在申報遺產稅時，不再將土地申報為農用農地或公設地，以規避農用農地及公設地依法律規定的使用限制。

關鍵字

財富流動性；代際彈性；遺產稅；租稅規避

並列摘要

Although much research has paid attention to inequality, the study on the intergenerational mobility of economic resources is relatively limited, especially intergenerational wealth mobility. Since wealth is more concentrated in the wealthy than income, the discussions of wealth mobility can provide a better understanding of the shape of wealth distribution and policy implications of redistribution in Taiwan. The first essay uses estate tax return data from 2001 to 2018 to present the wealth mobility in Taiwan. Results show that wealth mobility in Taiwan is higher than most countries around the world. However, there exists heterogeneity in wealth mobility across wealth quintiles: the extent of wealth rigidity in the fifth quintile is higher than first quintile. The low wealth mobility of the richest families caused the wealth hereditary which is harmful to improve the wealth distribution in Taiwan. The second essay examines the impact of parental wealth composition, regional heterogeneity, and estate tax on wealth mobility in Taiwan. In terms of parental wealth composition, parents pass on their knowledge, preferences, and styles of asset allocation to their children, which makes the decision of saving and wealth composition similar between the two generations, leading to the correlation between the wealth of parents and children. This paper estimates the intergenerational elasticity of financial assets and real estate. Results show that the intergenerational elasticity of financial assets is higher than the one of real estate, suggesting that financial assets have higher intergenerational rigidity. In addition, the more wealth parents allocate to financial assets, the higher the level of their children's wealth status. This result suggests a tendency to hold financial assets instead of real estate in Taiwan. Furthermore, in terms of regional heterogeneity, the empirical results show that children whose residence is municipality face a higher probability of having a higher wealth level and higher wealth status than their parents, indicating that the disparities between urban and rural areas have multi-generational effects on wealth accumulation. Finally, this paper exploits the exogenous changes in the estate tax rate since 2009 to examine the impact of the estate tax on wealth mobility. Difference-in-differences estimators suggest that wealth mobility decreased after the estate tax cut. The third essay also applies the estate tax reform in 2009 to investigate the causal relationship between estate tax burden and tax avoidance. DID regression results suggest that the 2009 tax cut reduced the incentive to the holding of instruments of tax avoidance (farmland, land reserved for public facilities, and debt). These reductions reflect the changes in reporting behavior instead of changes in real investment decisions in response to estate tax cut.