An international study of bank interest margins

This paper studies the determination of bank interest margins. Using international panel data, our empirical evidence shows that both portfolio risk and non-risk factors generally affect bank interest margins. However, when countries are divided into high- and low-income sub-samples, credit risk is the most important factors in determining interest margins for high-income countries whereas operating costs and market structure are the most powerful force for low-income ones. The data thus suggest that policies toward cost saving and anti-monopoly are likely to have larger impact on interest margins for the low-income countries.