VIX is the ticker symbol for the Chicago Board Options Exchange Volatility Index, a popular measure of the implied volatility of S&P 500 index options. A high value corresponds to a more volatile market and therefore more costly options, which can be used to defray risk from volatility.[1] If investors see high risks of a change in prices, they require a greater premium to insure against such a change by selling options. Often referred to as the fear index, it represents one measure of the market's expectation of volatility over the next 30 day period.
