The comeback of the volatility in January has taken both bulls and bears by surprise. In fact, tensions between USA and Iran, the coronavirus outbreak in China and the start of Q4 2019 earnings season have sent equities (and all asset classes in general) flying into different directions within a few weeks ; enthusiasm has been followed by fear (and vice versa), corrections were abrupt and short lived, rebounds were strong (all of these moves being as wellargued as a bunch of tweets).