## Label Key

What key contains the labels. The value of each label key will be the X tick values if group by keys or the legend if group by labels.

### Example

In this example dataset:

Size | Red | Green | Blue
--- | --- | --- | ---
Small | 5 | 10 | 15
Medium | 25 | 30 | 35
Large | 50 | 60 | 70

The label key would be Size

### Caution

Ensure the label key is not also selected in "Keys" as it will cause duplicate columns and break some visualisations.