Showing additional data values in tooltips
You can display additional measures as tooltips when hovering over a point in the visualization.
Click the Fields icon to open the Fields pane, then drag the one or more
measures with the corresponding values you want to show to the Tooltip data
field. You can also click an empty Tooltip data field and select the measures
that you want to display.
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For more information, see Showing additional data values in tooltips.