I've market the original study date on the chart. Up to that point there had only been 2 out of 12 instances that rose the next day. Since then it's been a coinflip but the gainers have strongly outsized the losers.
In the original post I listed all of the instances up to that point. Below I have listed all the instances since then. Market behavior is always evolving. It is important to continually monitor edges to make sure they are still providing an edge. This is something I constantly do in the Subscriber Letter. Over the last year and a half since I first published the study the market has: 1) Shown a much greater inclination to experience these late-day market surges. There have been more instances in the last 2 years than in the previous 25 years. 2) With the market more inclined to experience a surge, it's meaning also seems to have changed. It no longer seems to suggests a downward edge for the next day.