From AlphaTrends:
During the 2000-2003 bear market, the SPY made 9 significant drives lower and 8 recovery rallies. The average decline was 18.85% and the average recovery rally was 17.40% which means the market recovered an average of 73.06% of the prior loss. The speed and magnitude of the rallies in a bear market are quite seductive, but being early is just not worth the losses....
...Notice the DIRECTION of the 200 day (40 week) MA, it did not turn higher until April/May 2003. As long as the 200 DMA is declining all rallies should be expected to fail.