Three black crows
Three straight bearish one-minute candles, each closing lower and opening inside the one before: a short selling run.
Three Black Crows checks the last three candles on each bar. All three must close below their open, each close must be lower than the one before, and each candle must open inside the real body of the candle before it. It reads only opens and closes, so highs and lows are passed in but unused.
How to read it
- Each marker is the third candle of a run: three one-minute candles that each closed lower, drawn on the bar where the third one closes.
- A marker means short-term selling pressure is already under way, not a call that the move will reverse.
- The rule can hold again on the next bar while selling continues, so consecutive markers mean a sustained run.
What it outputs
- Three black crows
- True on the bar that closes the third candle of a bearish run that meets every rule; False on other bars.
When it fires
Fires on the bar that closes the third of three bearish candles, each closing lower than the one before and opening inside the prior real body. On the default SPY sample it fired on 0.65% of bars: 113 events, about 5 per day.
Pitfalls
- The docstring says strong candles, but the code sets no minimum body or wick size. Small bearish candles with lower closes qualify, so many one-minute markers are small noise.
- The marker prints only after the third candle closes, so price has already fallen for three minutes by then.
- The open tests are strict. A candle that opens exactly at the prior close, or level with the prior open, fails, so some runs that look bearish on the chart do not mark.