Optimal Capital Adequacy Ratios for Commercial Banks: Empirical Evidence from Vietnam

It is unavoidable for businesses, especially commercial banks, to compete with other firms and financial institutions in a globalized and internationalized world. Basel I, II, and III were developed by the Basel Committee on Banking Supervision with the primary purpose of supporting banks in dealing with potential risks and enhancing their ability to absorb losses. Basel II and III require the minimum capital adequacy ratio (CAR) of 8% and 10.5%, respectively. This paper estimates the optimal CAR of 26 commercial banks in Vietnam from 2016 to 2020 using the two-stage DEA method. According to the empirical findings, banks with ideal CARs exceeding 8% (as defined by Basel II) and 10.5 percent (as defined by Basel III) account for approximately 98 percent and 88 percent of all banks, respectively. Furthermore, 75.83 percent of all banks need to boost their existing CAR to achieve the optimal level of CAR as well as obtain the best performance. On average, the optimal CAR of state-owned banks is higher than other joint-stock banks, respectively 26 percent and 19 percent. Consequently, it is recommended for Vietnam commercial banks to reach optimal CAR and comply with the new policy set by Basel III with the purpose of approaching the efficient frontier.