Computes the rate needed for an investment to reach a specific value within a specific number of periods.
RRI(total_periods, present_value, [future_value])
- total_periods - The total number of payment periods in which the investment can grow.
- present_value - The present value of the investment.
- future_value - [OPTIONAL] The desired future value of the investment.
RRI(1,10,0) returns -1, the equivalent interest rate for the growth of the investment from 10 to 0 over 1 period.
RRI(12,1000,1100) returns an equivalent interest rate for the growth of the investment from 1000 to 1100 over 96 periods.
- All values must be positive. total_periods and present_value must be greater than 0.
- If future_value is 0, the rate returned is -1.