What is Annualized Volatility?
Annualized volatility is a standard deviation of returns scaled to a one-year period. A daily figure is usually multiplied by the square root of about 252 trading days, and a monthly figure by the square root of 12. The scaling assumes each period's return is unrelated to the last.
Why Annualized Volatility matters
Volatility figures are only comparable when they are quoted over the same period.