The VSTOXX indices track real-time options prices for the EURO STOXX 50, thus reflecting market expectations of future volatility – also known as implied volatility – in Eurozone stocks. As markets fall or rise, prices for options tend to move in opposite direction. This responds to investors and traders buying or selling protection against increasing future moves, prompting changes in implied volatility.
A two-step process leads to the determination of the level of a VSTOXX index:
In the first step, EURO STOXX 50 options traded on Eurex are grouped by maturity. For each of the first eight standard maturities available, a portfolio is constructed that determines the implied volatility of the EURO STOXX 50 for that maturity: this will be referred to as a VSTOXX sub-index of a certain tenor.
In the second step, a target tenor for volatility is identified: for instance, a constant 30-day volatility. To achieve this constant time to maturity, the average of two sub-indices is calculated. The two elected sub-indices will have the closest (variable) time to maturity to the targeted, fixed term and be weighted in such a way that the resulting combined time to maturity matches the targeted one. The resulting average is called a VSTOXX main index and represents the implied volatility of EURO STOXX 50 over the targeted term.
Although the main index VSTOXX 30 days is the most popular one – and is usually referred to as the VSTOXX – eleven other main indices are calculated, covering fixed maturities up to 360 days in increments of 30 days.
For more on the VSTOXX methodology, please click here