Obv ma cross down event
Fires when the running volume total (OBV) dips below its own average, a turn toward net selling volume.
This indicator does not cross price. It builds OBV, a running total that adds each bar's volume on up-closes and subtracts it on down-closes, then averages that total over ma_window bars (an exponential average by default). It marks the bar where OBV falls below that average after being at or above it on the bar before.
How to read it
- Markers sit on the candles, one per event, on the bar where the cross happens.
- Each marker is a single-bar pulse: volume flow has just dipped under its average, not held there.
- At defaults it fires on about 5% of bars on SPY one-minute data, roughly 49 times a day, so read clusters rather than single markers.
- A marker means recent volume leans toward selling against its own trend; it is not a price forecast.
What it outputs
- OBV below its average
- A one-bar marker on the bar OBV drops below its moving average, having been at or above it on the bar before.
When it fires
When OBV falls below its average on a bar where it was at or above that average on the bar before. It means net volume flow has just turned down against its recent trend. On the Sept 2026 SPY sample this happened about 49 times a day.
Settings
- ma_window
- Bars in the average that OBV is compared against. Short values (5 to 20) hug the line, so crosses come often. Long values (100 or more) give fewer crosses, each a slower turn in volume flow. At 1 the average equals OBV, so nothing fires.
- ema
- 1 uses an exponential average that weights the newest bars more, so it reacts sooner to the latest move. 0 uses a plain average where every bar in the window counts equally, so the newest bar moves it less.
Pitfalls
- The name says cross, but it is OBV crossing its own average, not price crossing a moving average. Read it as a volume-flow event.
- It is frequent at defaults, so most markers carry little information alone. The sample shows how often it fires, not whether those moves lead price.
- The average is seeded from the first OBV value on the chart, so early crosses rest on fewer bars than later ones.