---
title: rate
framework: realitykit
role: symbol
role_heading: Instance Property
path: realitykit/spatialforcefalloff/rate
---

# rate

The spatial falloff / attenuation rate.

## Declaration

```swift
var rate: Double
```

## Discussion

Discussion An exponent that determines how the effect’s strength diminishes with distance. Use a non-negative rate. When the rate is 0, no falloff occurs. When the rate is greater than 0 and less than 1.0, falloff occurs slower and is sublinear. When the rate is 1.0, falloff is linear. When the rate is greater than 1, falloff occurs faster and is nonlinear.