I analyzed 13,000 Wyckoff accumulation signals over 20 years. Here are the patterns that actually surprised me.

I posted here a few days ago about how I use volume to spot institutional accumulation. A lot of people had great questions about whether the method actually holds up statistically so I want to share what I found after going deeper into the data.

I ran the system across 185 large cap US stocks from 2006 to 2026. It detected 13,093 accumulation signals total. Every signal was tracked at 5, 10, 20, and 40 trading days to see what happened next. The overall win rate at 40 days was 65.1% with average winners of +9.06% and average losers of -6.64%. Statistically significant at p < 0.001 with a z-score of 34.56.

But the headline number is not what surprised me. Here are the things that actually changed how I think about this.

The longer you hold the better it gets. At 5 days the win rate is only 57.5%. Not bad but nothing special. By 40 days its 65.1%. Accumulation is a slow process and the payoff takes time to show up. If you are trying to scalp an accumulation signal on a 2 day hold you are leaving most of the edge on the table. This is a swing setup through and through.

The worst losses come right before nobody expects it. In January and February 2020 the system was firing strong signals on stocks like MSFT, Hilton, Eaton, Lululemon, PayPal. Scores of 8 and 9, real accumulation patterns with volume confirmation. Then COVID hit. Hilton dropped 48% in 40 days. Lululemon dropped 44%. Eaton dropped 29%. Every one of those signals got destroyed. The system was reading the structure correctly, institutions were accumulating, but a once in a century pandemic overwhelmed everything. No pattern based system survives that kind of macro shock and anyone who tells you otherwise is lying.

But here is what surprised me. The system caught the recovery. In June 2020 while most people were still scared to buy, the system started flagging accumulation again. Square got flagged on June 9 with a score of 8. 40 days later it was up 63%. The Trade Desk got flagged in September with a score of 8. 40 days later it was up 78%. Axon flagged in December, up 59% in 40 days. MongoDB flagged in December, up 46%. These were not lucky picks. The volume structure was showing institutions stepping back in while retail was still frozen on the sidelines.

That recovery pattern is exactly what Wyckoff described a hundred years ago. Panic selling creates a Selling Climax. Smart money absorbs the supply. Price stabilizes. Then when everyone else finally realizes the bottom is in, the markup has already started. The system just reads the volume to tell you when the absorption is happening.

The win rate improved further when multiple timeframes confirmed the same accumulation pattern at the same time. All results are statistically significant well beyond p < 0.001.

Winners are always bigger than losers. Across every measurement window the average winner was larger than the average loser. At 40 days winners averaged +9.06% versus losers at -6.64%. That means even at a 50% win rate you would still make money. The actual win rate being above 65% is extra margin on top.

I track every signal going back to 2006 with full return data at every measurement window. Every signal independently verified against live market data. I also log every new detection in real time so you can track whether current signals play out going forward.

Not financial advice. Historical patterns do not guarantee future results. But 13,000 signals over 20 years including a global pandemic is about as stress tested as it gets.