The volatility of a stock is defined to be the standard deviation of the stock's return over a certain length of time. A sample of 12 consecutive monthly returns for stock ABC is provided below. The returns are provided as percentages.

2.1	-1.1	0.5	-0.7	2.3	1.8
2.9	-1.1	-0.6	2.5	-1	2.5

Use the 1-Var Stats calculator function and this sample information to estimate the monthly volatility for the stock . In other words, find the standard deviation for the sample of monthly returns.

Multiply this number by 12 to find the annual volatility of the stock.

Express your answer as a percentage. Round your answer to two decimal places.

The answer is 19.77. Can you write out the steps on how they got the answer? Thank you!