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# AudioUnitParameterHistoryInfo

The suggested update rate and history duration for parameters which have the [`flag_PlotHistory`](/documentation/AudioToolbox/AudioUnitParameterOptions/flag_PlotHistory) flag set.

```
struct AudioUnitParameterHistoryInfo
```

## Overview

The structure is filled out by getting the value of the `kAudioUnitProperty_ParameterHistoryInfo` property.

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