R Interest Rate. The calculation assumes constant compounding over an infinite number of time periods. In the example you can see this more-or-less works out.
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The compound interest formula solves for the future value of the investment. For daily compounding most organizations use 360 or 365. Where P Principal amount Present Value t Time. Continuous Compounding Formulas n Calculate Accrued Amount Principal InterestA Pert Calculate Principal Amount solve for PP A e rt Calculate rate of interest in decimal solve for rr ln AP t Calculate rate of interest in percentR r 100 Calculate time solve for tt.