可轉換公司債之融資決策與轉換後之長期績效

Abstract

可轉換公司債賦予債權人於未來擁有可成為發行公司股東的權利，如同許多一般證券，過去已有許多文獻探討其發行後發行公司的股價表現，但鮮少有學者研究其轉換後的長期績效。本文將回溯各可轉換公司債發行公司於發行後何時股價超過轉換價格，視此一情況代表其可轉換公司債將被執行轉換權的時間點，進而探討發行公司於可轉換公司債被轉換後的長期績效。 許多公司發行可轉換公司債具有替代一般公司債 (Green , 1984)與普通股 (Stein, 1992)的發行動機，故在不同動機下，分析發行公司於可轉換公司債被轉換後的長期績效是否有異。另一方面，建立一些財務資訊來解釋可轉換公司債的融資決策，本文採用期間模型來進行實證研究。 實證結果發現，可轉換公司債於轉換後其發行公司的股價表現是逐年下跌，而權益型與債券型可轉換公司債相比，此效果更是明顯。藉由期間模型，發現當對未來景氣樂觀，融資規模低、公司規模小與未來投資成長機會大時，易促使公司發行權益型可轉換公司債來減少發行新股所帶來的權益融資成本。反之，當公司規模大、總風險小、槓桿使用程度低與未來投資成長機會不樂觀的情況下，易增加公司發行偏向債券型證券的可轉換公司債來減少發行公司債所帶來的融資成本。

In the past, there was lots of literatures treating firms' performance after issuing convertible debt, but few scholars tended to discuss the long run performance after conversion. It is difficult to collect the information about the date when the convertible is converted on. Therefore, in this study, we treat the case where the price exceeds the conversion price as the timing of conversion. Then, we exam the long run performance after conversion. Literatures suggest that convertible debt reduces the debt- and equity-related costs of external finance, so many firms issue convertible debt instead of standard securities such as straight debt (Green, 1984) or common equity (Stein, 1992). This paper also contrasts the long-run abnormal returns after conversion based on two different incentives. Besides, we try to explain the firms’ financing decisions to issue convertible debt by adopting the duration model. The result indicates that firms on average perform poorly in the long time after conversion, particularly for equity-like convertible debt. Moreover, it reveals that the business cycle, firm size, offer size, stock volatility, financial leverage and future investment opportunities have significant influence on the financing decisions of issuing convertible debt.