# Percentage

{% hint style="success" %}
This is the official documentation of the `@forestadmin/agent` Node.js agent.
{% endhint %}

![Percentage Chart example](https://3861847666-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F9UN5oBJhgzLadOqi7jx6%2Fuploads%2Fgit-blob-159b56e55b9ec17e277a0ecf21245ffe30988355%2Fchart-percentage.png?alt=media)

Percentage Charts are very similar to value charts. The range of valid values to be returned is from 0 to 100.

```javascript
agent.addChart('averageVolumeIncrease', async (context, resultBuilder) => {
  // [...]

  return resultBuilder.percentage(11);
});
```