The various interpretations of put/call ratios are as diverse as the number of traders who view them. Typically they are used contrarian-wise, a high Put/Call ratio signals an over-cautious investor universe and thus is bullish (and vice versa) but in recent years that has been much less evident. Currently, the index-based put/call ratio is at 1.80 - the highest since May 2012, having been notably above 1 (i.e. more puts than calls) for most of the days since the Bullard lows.
Put/call ratio (rebased around 1 for clarity) is at its highest since May 2012...
Of course, there is one difference now... no QE (in the USA)