signals / Williams %R cross -80
Williams %R cross -80 is a long-side study. Fires when Williams %R crosses above -80 (leaving oversold).
FAQ
What is Williams %R cross -80?
Williams %R cross -80 is a long-side study. Fires when Williams %R crosses above -80 (leaving oversold).
Which names are firing it?
Among mega-caps in the last 5 daily bars: KO, JNJ, JPM, MRK, LLY, META, CRM, PEP, HD, NFLX.
What is the sample?
Hit rates use the same rank engine as /t/spy on a fixed sample (SPY, SPX, QQQ, IWM, AAPL, MSFT, NVDA, TSLA). 8 of those names have a measurable history for this rule. Windows are 5 days, 1 month and 3 months on daily bars. Last bar in sample: 2026-10-12. Method: /methodology. Caveats: /help.
What does Williams %R cross -80 measure?
Fires when Williams %R crosses above −80 (leaving oversold). Underlying math: see How it works on this page. Catalog line: Fires when Williams %R crosses above -80 (leaving oversold).
What does a firing mean?
A firing is the daily bar where this rule’s condition becomes true (a cross or a flip). It is a study event, not a recommendation to buy or sell. Forward windows on this site are close-to-close with no costs. Study side is long-side (LONG). A positive forward return is a rise in the close after the print — a scoring convention, not a recommendation to buy. Method: /methodology.
Why can the sample be small?
Hit rates need enough dated prints with a completed forward window. A row with fewer than 10 firings is anecdote, not evidence — the same caveat as /help. Slow rules (especially 50/200 SMA crosses) often have single-digit counts on a two-year tape. We do not invent a hit rate when the count is missing. Names in this sample with a measurable history include SPX · QQQ · AAPL · SPY.
How it works
Williams %R on daily bars with period 14: %R = −100 × (14-bar high − close) / (14-bar high − 14-bar low). Scale runs from 0 (high) to −100 (low). A firing is a cross of −80 or −20, not a stay inside the zone.
Fires when Williams %R crosses above −80 (leaving oversold).
Definition comes from the rank-rule catalog and the indicator defaults in this repo. Slug williams-r-cross-minus-80 is listed on /api/meta.
How to read it
Study side is long-side (labeled LONG on firing chips). A positive forward return on this page is a rise in the close after the print. That is how the event is scored — not a recommendation to buy. Williams %R is a stochastic-style oscillator inverted to a 0…−100 scale. Crossing −80 / −20 is the same family of “leaving an extreme” event as RSI 30 / 70. Read it as a dated cross, then the side-adjusted forward windows — not as a timing recommendation.
Scoring on this site is shared across every rule (5-day / 1-month / 3-month close-to-close windows, side-adjusted). See How it is scored here below. Names in the tracked sample with a measurable history include SPX · QQQ · AAPL · SPY. Those figures are the same rows as the hit-rate table below — not a second ranking. Historical hit rates, not a prediction / not trade advice.
When it fails
- Like other oscillators, %R can remain extreme while the trend continues.
- A flat high-low range makes %R jumpy (small denominator).
- −80 / −20 are conventional lines, not fitted parameters.
- Past ≠ future. A historical hit rate is not a prediction and not investment advice.
- No costs modeled. Forward returns are close-to-close with no commissions, slippage or borrow.
- Small samples. A row with fewer than 10 firings is anecdote, not evidence.
- Overlap bias. Clustered prints can credit the same later move more than once.
Same caveats as the rest of the site: /methodology · /help.
How it is scored here
On this site every rule is scored the same way: run it over about two years of daily bars, record each firing, and measure what the name did 5 days, 1 month and 3 months later. Sell signals are measured as shorts, so a positive return is a profitable short (side-adjusted). The composite score is 0.6 × average return + 0.4 × (win rate − 50), with longer horizons weighted more. Nothing here is a forecast.
Full catalog: /signals. Method: /methodology. Slug williams-r-cross-minus-80 is stable and listed on /api/meta.
Same family: Williams %R cross -20
Firing now (mega-caps, last 5 bars)
| Symbol | Last date | Win 1mo | Count |
|---|---|---|---|
| KO | 2026-10-08Win 75.0% · n=28FIRED | 75.0%n=28 | 28 |
| JNJ | 2026-10-07Win 72.0% · n=25FIRED | 72.0%n=25 | 25 |
| JPM | 2026-10-08Win 65.4% · n=26FIRED | 65.4%n=26 | 26 |
| MRK | 2026-10-06Win 62.1% · n=29FIRED | 62.1%n=29 | 29 |
| LLY | 2026-10-06Win 50.0% · n=32FIRED | 50.0%n=32 | 32 |
| META | 2026-10-12Win 50.0% · n=40FIRED | 50.0%n=40 | 40 |
| CRM | 2026-10-08Win 45.5% · n=33STUDY | 45.5%n=33 | 33 |
| PEP | 2026-10-08Win 41.5% · n=41STUDY | 41.5%n=41 | 41 |
| HD | 2026-10-06Win 41.2% · n=34STUDY | 41.2%n=34 | 34 |
| NFLX | 2026-10-06Win 37.1% · n=35STUDY | 37.1%n=35 | 35 |
Hit rates on tracked names
Same rank engine as /t/spy, /t/nvda, and /t/spx, restricted to this rule.
| Symbol | Win 5d | Win 1mo | Win 3mo | Count | Last bar |
|---|---|---|---|---|---|
| QQQ | 54.5% | 78.1%n=32 | 82.1% | 32 | 2026-10-12 |
| AAPL | 59.3% | 77.8%n=27 | 72.0% | 27 | 2026-10-12 |
| SPX | 53.3% | 79.3%n=29 | 78.3% | 29 | 2026-10-12 |
| SPY | 50.0% | 75.9%n=29 | 73.9% | 29 | 2026-10-12 |
| IWM | 40.6% | 70.0%n=30 | 80.0% | 30 | 2026-10-12 |
| NVDA | 62.9% | 47.1%n=34 | 67.7% | 34 | 2026-10-12 |
| TSLA | 55.9% | 48.5%n=33 | 56.2% | 33 | 2026-10-12 |
| MSFT | 57.7% | 44.0%n=25 | 54.2% | 25 | 2026-10-12 |
Honest caveats
- Past ≠ future. Everything here is a historical measurement on daily bars, not a prediction and not investment advice.
- No costs modeled. Forward returns are close-to-close with no commissions, slippage or borrow.
- Overlap bias. Signals that fire in clusters get credit for the same move more than once.
- Small samples. A row with fewer than 10 firings is anecdote, not evidence.
Full method: help manual. Interactive chart: terminal.