租稅政策變動與市場反應－－公司治理調節效果

The Effect of Changes in Taxes Policy on Equity Prices: Adjustment Effect of Corporate Governance

租稅課徵直接影響股票投資報酬及企業未來現金流量，短期間必定對於資本市場產生重大的衝擊。租稅如何影響股東的利益，並反應在公司的股價上，取決於公司治理的良窳。因此，本文將公司治理納入租稅政策變動之市場反應議題，採事件研究法探討政府宣告課徵奢侈稅所引起的股票異常報酬，公司治理所扮演的角色及其調節效果。實證發現課徵奢侈稅的消息發布事件期間，營建業股價呈現顯著負向累積異常報酬，且公司治理較佳的公司受租稅變動的負面衝擊較小，而經理人持股比例對於租稅政策變動與股票累積異常報酬之關係確實存在調節效果。顯示公司治理降低了課徵奢侈稅的消息對股價之衝擊，確實能夠發揮穩定股價作用。因此，建議投資人在市場面對非預期因素的衝擊時，選擇治理機制良好的公司做為資金避風港。

Tax levy directly affects the returns on equity investment and company’s future cash flows, resulting in a significant impact on the capital markets within a shortrun. Corporate governance is one of determinant factors to the way on how tax levy affects the shareholders’ interests and company’s share price. By introducing corporate governance into the issue on market reaction of tax policy changes, this paper, using the event study, aims to explore abnormal returns of share prices caused by luxury tax declaration with a discussion of how the role corporate governance plays and its moderated effects on abnormal stock returns. The empirical findings show that, during the event period of luxury tax declaration, the share prices of companies in the construction industry are significantly negative against the cumulative abnormal returns, while the companies with better corporate governance demonstrate smaller negative impacts. The results further suggest that the shareholding ratio of managers moderates the relationship between tax policy changes and the cumulated abnormal returns of share prices. It is suggested that corporate governance mitigates the adverse impact of luxury tax declaration on share prices and plays a role of share stabilization. Thus, it is recommended that the company with the sound mechanism of corporate governance is a haven for investments when investors confront the unexpected shocks in the stock market.