One of the methods to identifying market bottoms is to look at 52 week Highs and Lows. These are charts of New Highs and New Lows. For New Highs, the expansion seems to come well after the market bottom is put into place, so I wanted to map the trend of New Highs. I've found the Hull Moving Average
as one of the best identifiers of a trend, so the histogram for the New Highs is based on that. New Lows was a bit easier, market bottoms seem to be in place when New Lows stay consistently below 42. So, a combination of New Highs showing an uptrend and New Lows staying below 42 could be a potential signal that a market bottom is firmly in place. It is very clear for the March 2009 bottom, but not as clear for the 2003 bottom. Unfortunately, this data goes back to only 2001. What I'd really love to have is data going back into the 1960s.