This problem is most easily solved using a spreadsheet; for accuracy input percentages as decimals or use the % sign, do not input as if these were integers. Do not do any interim rounding, calculate values to 6 decimal places before converting to percentages, state the answer to two places, do not use labels (%, $). For example, if the value is 0.06458, the answer is 6.46.

Given the following information about past returns for Saphir Netmarketing, what is the standard deviation of returns?

Year	Return
1	12.00%
2	8.30%
3	-4.70%
4	-0.90%
5	5.70%