기업은 신용등급을 상향조정 시키기 위하여 이익을 조정하는가? 회사채를 발행한 한국 유가증권 상장기업을 중심으로

In this paper, we examine the relationship between credit ratings, credit ratings changes and earnings management. Since the 1997 Asian Financial Crisis, many listed firms collapsed, leading investors to suffer losses. As a result, credit ratings have become a very important indicators of firms’ financial stability for investors, government agencies and debt issuers and other stakeholders. Firms with a similar credit rating are grouped together as firms of similar credit quality (Kisgen 2006) because credit ratings provide an ‘economically meaningful role’ (Boot et al. 2006). Numerous studies find that managers care deeply about their credit ratings (Graham and Harvey 2001; Kisgen 2009; Hovakimian at al. 2009). Firms that borrow equity in the form of bonds may have incentives to increase credit ratings with opportunistic earnings management. A change in a firm’s credit ratings has a direct impact on a firm’s profitability. Firm’s benefit from better terms from suppliers, enjoy better investment opportunities and have lower cost of capital when their credit risk is lower. Firms incur a higher cost of debt and experience additional costs when their credit risk is higher. American studies find that firms use earnings management to influence credit ratings (Ali and Zhang 2008; Jung et al. 2013; Alissa et al 2013). Credit rating agencies have stated they assume financial statements to be reasonable and accurate (Securities and Exchange Commission, 2003; Standard and Poor’s, 2006) and they do not consider themselves to be auditors. They take the information in the financial statements as accurate. Therefore, there is a potential for managers to engage in earnings management to influence credit ratings. In South Korea, there have been numerous experiments with auditor legislation because of financial collapses due to earnings management in the 2000s. Therefore, a decomposition of the relation between opportunistic earnings management and credit ratings is an important consideration for Korean accounting academia. Previous Korean studies have examined whether credit ratings in period t are significantly related to level of earnings management in the same period; however, those studies fail to find the consistent results. It is widely known that credit rating agencies allow one year credit watch period to assess default risk before credit rating decision. Firms with an incentive to increase their credit ratings through earnings management will only realize if earnings management positively influences credit ratings in the following year. Therefore, we focus on establishing a relationship between the levels of earnings management at time t and credit ratings / changes at time t+1. Our study provides a more robust analysis by establishing if both accrual based and real earnings management in period t influences credit ratings and credit rating changes in period t+1. Using a sample of 1,717 Korean KRX firm-years from 2002 to 2013, we find a negative relation between earnings management in period t and credit ratings in period t+1, suggesting that firms with higher credit ratings have lower levels of earnings management. Moreover, we find that firms that experience a credit ratings change in period t+1 are less likely to engage in opportunistic earnings management in period t, suggesting that firms do not have the potential to increase credit ratings. We also find that firms that experience a credit rating increase in period t+1 have a negative association with opportunistic earnings management for accruals measures. Moreover, when we split our sample into firms that experience 1) a credit rating increase, 2) decrease and 3) remaining the same, we find that firms that engage in earnings management are more likely to remain unchanged or experience a credit rating decrease. Thus, taken together, we find no evidence of relationship between opportunistic earnings management and an increase in credit ratings in the South Korean public debt market. Our results may be of interest to regulators, credit rating agencies, market participants and firms that question whether level of earnings management in current year influences credit ratings in the subsequent period.