The underlying reason behind this seems to be a decline in the natural rate of interest that has caused a significant decline in nominal interest rates (Chart 13). Among the banks' two main businesses of settlement services and lending services, banks have been able to gain profits only from the latter business and have engaged in more intense interest rate competition.
As market interest 26  The natural rate of interest is an interest rate that balances savings and investment. It refers to the real interest rate that can be achieved when the real economy grows at its potential growth rate.