VelocityShares Daily 2X VIX Short-Term ETN TVIX -6.21% : -6.2%, The S&P 500 VIX Short-Term Futures Index measures the volatility of the S&P 500 Index via futures contracts as traded on the CBOE. iPath S&P 500 VIX Mid-Term Futures ETN VXZ -2.22% : -2.2%. The iPath S&P 500 VIX Mid-Term Futures ETN VXZ -2.22% is priced from the average volatility of the 4th through 7th month futures contracts of the S&P 500 Index as traded on the CBOE. S&P 500 Dynamic VIX ETF XVZ -0.76% : -0.8%. The S&P 500 Dynamic VIX Futures Total Return Index seeks to combine results of volatility of the S&P 500VIX Short-Term Futures Index Excess Return and the S&P 500 VIX Mid-Term Futures Index Excess Return to create an accurate market volatility reading, as measured by the CBOE. Velocity Shares Daily Inverse VIX Short-Term ETN XIV +3.09% : +3.1%. The S&P 500 VIX Short-Term Futures Index measures the volatility of the S&P 500 Index via futures contracts traded on the CBOE. Bottom Line: VIX ETNs can be difficult to trade due to the volatility and tracking error that can occur. However, great profit opportunities can be enjoyed by sophisticated traders with a proven plan. VIX at current levels likely points to higher VIX, lower stock prices ahead.