Stock market volatility continues to shock most market participants this fall with enormous swings occurring almost daily. Last Thursday, the Dow was down almost 300 points at its worst levels only to recover with a massive 552-point gain. That’s an incredible 850-point turnaround in the span of just four hours of trading.

The CBOE Volatility Index is designed to be a measure of volatility in the overall market. Without getting too technical, it is based on the volatility of S&P 500 options. The options are rotated in and out, as one month’s options expire and then a new month is added on.