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# kAudioUnitProperty_ParameterHistoryInfo

For parameters that have the [`flag_PlotHistory`](/documentation/AudioToolbox/AudioUnitParameterOptions/flag_PlotHistory) flag set, getting this property fills out the [`AudioUnitParameterHistoryInfo`](/documentation/AudioToolbox/AudioUnitParameterHistoryInfo) struct containing the recommended update rate and history duration.

```
var kAudioUnitProperty_ParameterHistoryInfo: AudioUnitPropertyID { get }
```

---

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