Overlays allow you to layer on additional series in an existing visualization. They allow you to create charts with similar types of data, and are useful in situations when you need to display series that have similar X-Axis values but need to be produced with different groupings and filters.
In order to add an overlay to an existing visualization, you'll need to click the "ADD AN OVERLAY" button at the top of the Configuration Panel.
When you click the button, the existing Configuration Panel will collapse and a new one will appear below it.
When the new configuration panel appears, you'll be able to configure it just like you did with the first overlay, with the exception that your choices for the X-Axis column will be limited to columns that have the same type of data as the first X-Axis column you selected.
Configuring Overlay Visualizations¶
When you add a new overlay and update your visualization, results from the new overlay will be displayed on your visualization using the secondary (right) Y-Axis. You can change how series in each overlay is displayed by opening the overlay configuration panel.
On this panel, you can change the chart type, axis, and color for your new overlay.
Changing Chart Types When You Have an Overlay
When you add an overlay on a chart, the chart display buttons that were there for a single series/grouping disappear. You now have to open the overlay configuration panel for each overlay to change its chart type.