CEO薪酬存續期間與信用評等之關聯性

Abstract

為了解決代理問題，如何設計一套良好的經理人薪酬制度，一直是學者討論的議題。本研究根據Gopalan et al. (2014)對經理人薪酬存續期間提供一套公式量化總經理薪酬存續期間，預期當公司給予總經理薪酬存續期間愈長，總經理較不會做出短視決策，會為公司長遠利益考慮，而擁有較好的償債能力特質，能使該公司的獲得較佳的信用評等，另外，針對上述假設進一步推論，以公司治理做為調節變數，本研究認為公司治理較佳的公司，不需以較長的薪酬存續期間約束經理人，也能消除經理人短視行為，因而減輕代理問題，預期減弱薪酬存續期間與信用評等的關聯性。 本研究使用美國上市櫃公司2006年到2015年資料為樣本，信用評等以Standard & Poor’s國內長期債權人的信用評等作為衡量信用評等之依據，實證結果發現當公司給予總經理較長的薪酬存續期間，該公司的信用評等會提升，結果為顯著正相關，與預期相符，除了統計上的顯著性，本研究亦探討經濟上的顯著性。另外，以公司治理為調節變數的實證結果則與預期不同，以獨立董事持股比(NDSH)為公司治理代理變數，實證結果為公司治理較佳的公司，會強化總經理薪酬存續期間與信用評等的關聯性，與預期結果相反，實證結果並不支持公司治理與薪酬存續期間存在替代關係；而以管理擴權指數(E-index)為公司治理代理變數，實證結果則不顯著。

One of the most widely discussed topics in the academic literature concerns how to appropriately structure an optimal executive compensation to mitigate agency problems. Prior literature does not provide a measure to quantify executive pay duration, which refers to the average period that it takes for managers’ annual compensation to vest. Using the executive pay duration measure developed by Gopalan et al. (2014), this study examines the relation between the executive pay duration and the firm’s credit rating. I expect that when the CEO is given a longer pay duration, the CEO is less likely to be short-term oriented, and he/she will have fewer incentives to manage the firm’s short-term performance. Gopalan et al. (2014) shows that when the company provides its CEO with a longer the pay duration contract, the company exhibits firm characteristics associated with better debt-paying abilities. Therefore, I predict that firms granting longer executive pay duration have better credit ratings. Moreover, better-governed firms have less need to offer longer-duration pay contracts to alleviate CEO myopia behavior and to mitigate agency problems, I expect that strong corporate governance weakens the effect of CEO pay duration on credit ratings. Using a sample of listed companies in the U.S. from 2006 to 2015, I find that when firms grant their CEO longer-duration pay contracts, they receive better credit ratings. This result is positive and significant, supporting my first hypothesis. The effect of CEO pay duration not only has a statistical significance, but also exhibits economic significance. However, the empirical result of my second hypothesis is not consistent with my prediction. I use two proxies of firm governance, (1) nonexecutive director’s shareholding (NDSH); and (2) entrenchment index (EI). The result of NDSH is opposite to my prediction, suggesting that better-governed does not weaken the effect of CEO pay duration on credit rating. This empirical result doesn’t support the substitute relationship between corporate governance and duration pay contract. Using EI to proxy for corporate governance does not yield significant result.