營所稅率調升與企業盈餘管理關聯性之探討

我國自2018年起調升營利事業所得稅稅率至百分之二十。本研究旨在探討營所稅稅率調增對公司的盈餘管理程度及虛減盈餘之行為是否增加，並探討獨立董監事比例高低對所得稅率調升後之盈餘管理行為是否有抑制效果。本研究以裁決性應計數衡量盈餘管理程度，並以我國2015年至2020年上市櫃公司之樣本進行迴歸分析。實證結果發現，所得稅率調升後，公司會增加盈餘管理的程度，且利用盈餘調減的手段減輕公司租稅負擔。再者，獨立董監事比例較高的公司，具有較好的監督機制，對於公司在營所稅率調升後之盈餘管理行為有抑制效果。

關鍵字

營利事業所得稅；盈餘管理；裁決性應計數；獨立董監事

並列摘要

Since 2018, Taiwan has raised the income tax rate of profit-seeking enterprises to 20%. This study aims to investigate whether an increase in income tax rate leads to a rise in the degree of earnings management and the behaviors of falsely deducting firms’ earnings. In addition, this study examines whether the proportion of independent directors and supervisors could mitigate the firms’ earnings management behaviors following such an adjustment in the income tax rate. This study employs discretionary accruals to measure the degree of earnings management and conducts regression analyses by sampling publicly listed Taiwanese firms from 2015 to 2020. The empirical results indicate that the degree of earnings management increases and that the firms use earnings reduction strategies to reduce their tax burdens after the rise in tax rates. Furthermore, firms with a higher proportion of independent directors and supervisors have a better monitoring mechanism, which has a mitigating effect on firms’ earnings management behaviors after the increase in tax rates.