Question 308 risk, standard deviation, variance, no explanation
A stock's standard deviation of returns is expected to be:
- 0.09 per month for the first 5 months;
- 0.14 per month for the next 7 months.
What is the expected standard deviation of the stock per year ##(\sigma_\text{annual})##?
Assume that returns are independently and identically distributed (iid) and therefore have zero auto-correlation.