However, the bank will advertise the stated rate of interest being 20% despite the effective interest rate of 21.93%. In case of you being an investor, a bank might advertise effective interest rate rather than stated interest rate as it would look to the consumers that they are being offered higher interest amount. Effective interest rate (continuous compounding) = e i – 1. Where e = 2.71828. Example. Calculate effective interest rate for a loan with a nominal interest rate of 10% for (a) semiannual, (b) quarterly, (c) monthly and (d) daily and (e) continuous compounding. Solution. Effective interest rate for semiannual compounding = (1 + 10%/2) 2 – 1 = 10.25% Example Effective Annual Interest Rate Calculation: Suppose you have an investment account with a "Stated Rate" of 7% compounded monthly then the Effective Annual Interest Rate will be about 7.23%. Further, you want to know what your return will be in 5 years. Using the calculator, your periods are years, nominal rate is 7%,