If we take a look at historical times when this percentage of stocks above the 20 day average have hit below 20% we often will see a new high or at least a nice big move to the upside on the overall market. 
QQQ
QQQ 
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Disclaimer
The information and publications are not meant to be, and do not constitute, financial, investment, trading, or other types of advice or recommendations supplied or endorsed by TradingView. Read more in the Terms of Use.