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  "title" : "scrollingDeltaY"
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# scrollingDeltaY

The scroll wheel’s vertical delta.

```
var scrollingDeltaY: CGFloat { get }
```

## Discussion

This is the preferred property for accessing [`NSScrollWheel`](/documentation/AppKit/NSScrollWheel) delta values. When [`hasPreciseScrollingDeltas`](/documentation/AppKit/NSEvent/hasPreciseScrollingDeltas) is <doc://com.apple.documentation/documentation/Swift/false>, multiply the value returned by this method by the line or row height. Otherwise scroll by the returned amount.

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