Weekly Chart: Relative Implied Volatility – VIX/RVX ratio

For each investor, there are several ways of measuring the market’s temperature. For instance, former Fed chairman Alan Greenspan would look at the 10-year US yield, some investment managers will simply look at the VIX and currency traders will tend to watch the moves on the Japanese Yen, especially against the US and Australian Dollar (see AUDJPY and SP500 correlation here). We know empirically that a sudden move on the Yen (JPY appreciates relative to other currencies) is usually accompanied with an equity correction and hence an increase in the implied volatility. Even though we hear a lot about the VIX measure, we also need to pay attention to the implied volatility surface, presenting skew/smiles features and term structure, and compare it relative to other equity markets and asset classes. For instance, a couple of measures we like to watch are the VIX/Skew (here) and the VIX/VXV (here) ratios.

Hence, in today’s article, we present the VIX/RVX, which measures the ratio between the implied volatility of the SP500 and the Russell 2000, a small-cap stock market index. As you may know, the ‘small cap premium’ has been a crowded study in the empirical academic research, which started from the early work of Rolf Banz (1981) who founded that ‘smaller firms have had higher risk-adjust returns, on average, than larger firms’. Then, in their paper The Cross-Section of Expected Stock Returns (1992), Fama and French found that value and small cap stocks, on average, outperform growth and large carp stocks. As you can see it on the chart, an interesting development has occurred over the past few days following the huge spike in volatility. The VIX/RVX, which has constantly been above parity since 2006, is now sitting at 0.83. In other words, according to the index, the Russell 2000 equity market carries less risk than the SP500. The question now is: what explains this sudden drop in the ratio?

If we look at the week-on-week change in both indexes, we can first notice that, at current levels, the WoW change of 11.6 in the VIX came in at 5th position in the index history, just a 0.3 ‘shy’ of the October 1997 move (here). However, if we now look at the change in the implied volatility of the small caps, the RVX index barely changed (+2.3) over the past week, meaning that the drop in the ratio was only coming from the VIX move (here).

Hence, this leads us to an interesting conclusion: it seems that there is much more financialization going on with the VIX than with the RVX, either through the creation of single and double-levered long and short VIX ETFs products, or from a volatility-targeting and risk-parity perspectives (are those strategies more oriented towards the SP500?).

Chart: Relative Implied Volatility – VIX / RBX ratio (Source: Eikon Reuters)

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