CBOE Volatility Indexes
The Chicago Board Options Exchange (CBOE) calculates and updates the prices of a number of volatility-related indexes, each of which is a key measure of market expectations of near-term volatility conveyed by stock index option prices. The VIX, introduced at CBOE in 1993, and other volatility contracts have become a highly successful contract group for CBOE. Through the middle of 2007, open interest in VIX options was some 1.7 million contracts, with roughly 1.2 million constituting calls. 
These volatility indexes measure the market's expectation of 30-day volatility implicit in the prices of near-term index options. The indexes are quoted in percentage points, just like the standard deviation of a rate of return, e.g., 19.36. CBOE disseminates the index values continuously during trading hours.
CBOE Volatility Products
- CBOE Volatility Index (VIX)
- CBOE DJIA Volatility Index (VXD)
- CBOE NASDAQ Volatility Index (VXN)
- CBOE Russell 2000 Volatility Index (RVX)
- CBOE S&P 100 Volatility Index (VXO)
- CBOE S&P 500 VARB-X Strategy Benchmark(VTY)
- CBOE S&P 500 3-Month Volatility Index (VXV)
- CBOE VIX Premium Strategy Index (VPD)
- CBOE Capped VIX Premium Strategy Index (VPN)
- CBOE Volatility Index (VX)
- CBOE DJIA Volatility Index (DV)
- CBOE NASDAQ-100 Volatility Index (VN)
- CBOE Russell 2000 Volatility Index (VR)
Awards for VIX Products
- 2006 Leader in Options Innovation, Options on the CBOE Volatility Index for Most Innovative Index Derivative Award: 2006 Super Bowl of Indexing Conference
- 2004 Leader in Futures Innovation for the CBOE Volatility Index Futures (Most Innovative Index Derivative Award): 2004 Super Bowl of Indexing Conference
- Also see CBOE index options for a full listing of indexes traded on CBOE.
- CBOE Volatility Microsite 
- CBOE Volatility Indexes. Chicago Board Options Exchange.
- "THE STRIKING PRICE, LAWRENCE G. MCMILLAN, Modern Portfolio Protection”. Dow Jones.