RRI

RRI(nper, pv, fv)

Returns the equivalent interest rate for the growth of an investment.

nper	The total number of periods.
pv	The present value of the investment.
fv	The future value of the investment.

REMARKS

* This function was added in Excel 2013.
* The "nper" is the number of compounding periods.
* For the Microsoft documentation refer to support.microsoft.com
* For the Google documentation refer to support.google.com

	A
1	=RRI(4,9000,10000) = 2.67%
2	=RRI(10,50,100) = 7.18%
3	=RRI(PDURATION(5%,100,200),100,200) = 5.00%

1 - What is the equivalent interest rate when an investment increases from £9,000 to £10,000 over 4 periods.
2 - What is the equivalent interest rate when an investment increases from £50 to £100 over 10 periods.