In a table or a multi-column report, annotations can be added to allow commenting on a specific value within a report. There is no limit to the number of characters that can be added. Annotation icons appear to the left of the number being commented on, and the description can also be seen as a tool tip when you place the cursor on the icon. Additionally, the annotation is also displayed below the table.
To add an annotation:
Click the editor icon.
Click the value to add annotation. An editor box appears at the bottom of the report.
Add your annotation and click Save.
...