The multiple S9 signals in 2000 show the market is becoming increasingly fragile after the bullishness of the October B8 is exhausted by March,  The fragility of the market is also apparent if you notice that the declines are starting to dip regularly below the lower band, even though a new key price support line is becoming clear. The Presidential Election year helps hold up the market.  But there are too many S9s for any but the very nimbler and experienced to try to trade them.