自住與非自住之房屋稅率差異對房價之影響— 差異中之差異法的應用Effect of Tax Rate Difference Between Owner-occupied and Nonowner-occupied Houses on Housing Prices: Application of Difference-in-difference Method

高房價是臺灣近年來嚴重的社會問題，為了提高房屋持有成本、抑制房產炒作及保 障自住權益，政府在2014年6月修正房屋稅條例，將非自住住家用稅率由1.2%~2%提高為 1.5%~3.6%。本文整理臺灣地區20個縣市2010年第1季至2020年第4季共44季資料，採用差異中 之差異法(Difference in difference)，以直轄市為實驗組、非直轄市為控制組，比較兩組房價在 修法前後的差異，驗證修法對於高房價城市是否產生影響，結果發現直轄市房價上漲幅度在 修法後確實減少，租稅政策發揮抑制房價作用，且短期抑制效果較為明顯。本文研究發現可 提供政府對於未來是否應繼續實施租稅改革之參考。

關鍵詞：房屋稅、非自住房屋、差別稅率、房價、差異中之差異法

In Taiwan, high housing prices have been a serious social problem for decades. To raise the housing holding cost and curb real-estate speculation, the Ministry of Finance amended the House Tax Act in June 2014, raising the nonowner-occupied tax rate for residential purposes from 1.2%–2% to 1.5%–3.6%. This study uses the difference-in-difference method to compare the variances in housing prices between special municipalities (treatment group) and other counties and cities (control group). Our sample includes 44 quarters of data from 2010 to 2020 for 20 Taiwanese counties and cities, verifying the impact of the amendment policy on cities with high housing prices. Our results revealed that the increase in housing prices in special municipalities decreased after the amendment policy, indicating that the tax reform has inhibited housing prices.

Key words: House tax, Nonowner-occupied residential house, Differential housing tax rate, Housing prices, Difference-in-difference method