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# kCMTextMarkupAttribute_RelativeFontSize

A font size as a percentage of the current default font size.

```
let kCMTextMarkupAttribute_RelativeFontSize: CFString
```

## Discussion

This attribute’s value must be a non-negative `CFNumber`. This is a number holding a percentage of the size of the calculated default font size. A value of `120` indicates 20% larger than the default font size. A value of `80` indicates 80% of the default font size. The default value of `100` indicates no size difference.

---

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