Super-exponential growth expectations and the global financial crisis

Abstract

We construct risk-neutral return probability distributions from S&P 500 options data over the decade 2003–2013, separable into pre-crisis, crisis and post-crisis regimes. The pre-crisis period is characterized by increasing realized and, especially, option-implied returns. This translates into transient unsustainable price growth that may be identified as a bubble. Granger tests detect causality running from option-implied returns to Treasury Bill yields in the pre-crisis regime with a lag of a few days, and the other way round during the post-crisis regime with much longer lags (50–200 days). This suggests a transition from an abnormal regime preceding the crisis to a “new normal” post-crisis. The difference between realized and option-implied returns remains roughly constant prior to the crisis but diverges in the post-crisis phase, which may be interpreted as an increase of the representative investor׳s risk aversion.