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# falloff

The rate of decay for the field strength.

```
var falloff: CGFloat { get set }
```

## Discussion

This property defines how quickly the field strength diminishes as the distance from the field’s center increases. Falloff is not applied until the distance between objects is greater than the value in the [`minimumRadius`](/documentation/UIKit/UIFieldBehavior/minimumRadius) property.

The default value of the property is 0, which yields a uniform field that does not diminish over distance.

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