wcoop take 2

Volatility averages around 15%, is often within a range of 10-20%, and rises and falls over time. More recently, volatility has risen off historical lows, but has not spiked outside of the normal range.

In the stock market context, rapid price fluctuation in either direction is considered as volatility. Therefore, a high standard deviation value means prices can dynamically rise or fall and vice versa. In most cases, a surge or dive of 1% in market indexes classifies it as a volatile  market.