There is no 1920 low unless it's on the calendar. Once you start throwing out distant dates, whether it's Prechter's 1920 low or Dailio's 75-year cycle, there is a large amount of room for error, variation, or re-interpretation, regardless of whether the forecaster is good or not. I think the same skeptcism can be applied for forecasts that are too precise and appear to be just retrofitting analysis
1920's, actually 1921, start date is 5/2/21 about a third the way up to the peak before the low