국제 자본비용 모형을 이용한 한국기업의 자본비용 추정

Using International Cost of Capital Models (ICCM), we examine the method to estimate the cost of capital for Korean firms. A firm’s cost of capital is critical element in the process of long-term investment decision makings. It also serves as discount rate in estimating firm value. Investment companies and financial departments of Korean firms however use the traditional method which is based on ad-hoc approach to estimate the cost of capital. We show that ICCM can improve the accuracy of the estimation. Thereby, we demonstrate that ICCM provides a consistent and practical approach to estimate the cost of capital for Korean firms. ICCM estimates the cost of capital for Korean firms as if they are located in the developed countries and then adds the equity country risk premium associated with Korean country risk. Specifically, we use the historical average return on US treasury bonds as risk-free rate for Korean firms. The historical average US market risk premium is used as market risk premium for Korean firms. To accommodate the difference in country specific risk, we introduce Country Equity Risk Premium (CERP), which captures the additional risk premium for firms located in countries exposed to country default risk. There are diverse versions of ICCMs to calculate the equity country risk premium. We compute the equity country risk premium using the method in Damodaran (2006). Following his method, CERP is calculated by multiplying country default spread with the relative standard deviation between stock market volatility and bond market volatility. For an individual Korean firm, this equity country risk premium is adjusted with lambda, which represents the return sensitivity of individual company to the country risk premium. Finally, beta is estimated with industry average beta to avoid non-stationary nature of regression beta. Next, we also estimate the cost of debt using ICCM. The procedure is similar to the estimation of the cost of equity. Our initial estimation is based on the historical average data from the US capital market. Then, we adjust the number by incorporating country specific risk premium. Finally, the weighted average cost of capital for Korean firms can be estimated by utilizing market value weighted ratio of debt-to-capital and equity-to-capital. Using ICCM, we illustrate the procedure to calculate the cost of capital for an individual Korean firm. Using data of SK Telecom, which is one of the largest corporations in Korea, we compare the cost of capital estimated by the company with that of ICCM. We note that SK Telecom estimates the cost of capital with crude method that relies on recent date. While this practice is simple and thereby easy to compute the cost of capital, it may render biased estimates. We show that ICCM provides practically applicable and logical approach to estimate the cost of capital. Compared to the cost of capital estimated with ICCM, we find that SK Telecom underestimates the cost of debt and overestimates the cost of equity. For the weighted average cost of capital, it turns out that SK Telecom overestimates the cost of capital as compared to that estimated with ICCM. This suggests that the cost of capital used for internal decision makings may differ from what is perceived in the outside capital market. Nonetheless, the cost of capital estimated with ICCM provides valuable benchmark for the internal cost of capital. Given that the cost of capital is an important element for the company’s internal decision makings and valuation models, we show that ICCM approach has practical implication for a firm’s decision makers, investment companies and financial information service providers.