What the shape is

A flat upper boundary with rising lows beneath it. Its quality cannot be judged by how well a line fits, because a horizontal boundary has almost no variance to explain; each touch is instead required to sit within 18% of the formation height of its line.

What followed it

Horizon	Examples	Textbook direction	Median change	Middle half
5 bars	43	44.2% at or below a coin flip	+0.94%	-0.72% … +1.89%
10 bars	43	53.5%	+0.49%	-1.25% … +2.28%
20 bars	43	53.5%	+0.35%	-1.72% … +3.45%
60 bars	43	48.8% at or below a coin flip	-0.52%	-5.09% … +7.24%

10 instruments, 1d / 4h, 2017-08-17 to 2026-07-25 — 182,341 bars and 661 completed formations.

engine v1.0.0 · Record generated 2026-07-25

These figures describe past occurrences of the same shape. They are not a projection of this chart.
661 formations is not a large sample, and the instruments are correlated USDT pairs, so the effective sample is smaller still.
Below 30 examples no rate is printed at all.
Changes are close-to-close and exclude fees, funding and slippage.
Medians and quartiles pooled across instruments are sample-weighted approximations, not exact pooled quantiles.
A formation is timed from the bar its break became observable, and every change is measured strictly after that bar.
Pooled across every instrument and both backtest timeframes.

The same shape, split by interval

Interval 1d

Horizon	Examples	Textbook direction	Median change	Middle half
5 bars	2	too few examples	+4.10%	+4.10% … +4.10%
10 bars	2	too few examples	+13.95%	+13.95% … +13.95%
20 bars	2	too few examples	+16.04%	+16.04% … +16.04%
60 bars	2	too few examples	+16.38%	+16.38% … +16.38%

Interval 4h

Horizon	Examples	Textbook direction	Median change	Middle half
5 bars	41	43.9% at or below a coin flip	+0.78%	-0.95% … +1.78%
10 bars	41	53.7%	-0.17%	-2.00% … +1.71%
20 bars	41	51.2%	-0.42%	-2.59% … +2.84%
60 bars	41	46.3% at or below a coin flip	-1.35%	-6.14% … +6.79%

The backtest covered the daily and 4-hour intervals only. Only one shape reaches the publication floor on the daily, against eight on the 4-hour — so every pooled rate above is in practice a 4-hour statistic. The console scans five intervals; the three not listed here have no historical record at all.

How it is detected

Formations are matched against swing pivots rather than raw bars, so a single spiky candle cannot create one. A pivot is committed only once price reverses by more than 2.5 times ATR(14), floored at 0.8% of price. A detection is reported only at confidence 0.72 or above — the library default, unmodified.

Ascending triangle