On Thursday the DP Trend Model for SPY changed from BUY (long the market) to NEUTRAL (in cash or fully hedged) when the 20EMA crossed down through the 50EMA. Why doesn’t the model change from BUY to SELL (short the market)? Because the 50EMA is still above the 200EMA, which, by our definition, means SPY is still in a long-term bull market. In this type situation the Model design assumes the 20/50 crossover is only signalling a correction, not a bear market. If a correction turns into a bear market, the model is safely in cash.