90% days are not so easily to determine bottoms or tops till much later. IMHO
The record also shows that declines containing two or more 90% Downside Days usually persist, on a trend basis, until a strong, panic buying day occurs on which Upside volume equals 90% or more of the sum of Upside plus Downside Volume, AND on which Points Gained equal 90% or more of the sum of Points Gained plus Points Lost. These two combined events – panic selling (one or more 90% Downside Days) and panic buying (a 90% Upside Day) – represent a complete selling climax. Not all selling climaxes, as defined above, have occurred at major market bottoms. But, by observing the pattern of 90% Days, investors have been able to identify many important turning points in their very early stages. Before reviewing the historical record, here are a few general observations regarding 90% Days that may help to clarify some of the finer appraisal points associated with this very valuable indicator:
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