<div class='sourceset sourceset-common'>Common</div>

```kotlin
class Proportion(@FloatRange(0.0, 1.0) val proportion: Float) : PaneExpansionAnchor()
```

[PaneExpansionAnchor](/jetpack-compose/androidx.compose.material3.adaptive/adaptive-layout/classes/PaneExpansionAnchor) implementation that specifies the anchor position in the proportion of
the total size of the layout at the start side of the anchor.

#### Parameters

| | |
| --- | --- |
| proportion | the proportion of the layout at the start side of the anchor. For example, if the current layout from the start to the end is list-detail, when the proportion value is 0.3 and this anchor is used, the list pane will occupy 30% of the layout and the detail pane will occupy 70% of it. |