Data Bars is a way of visualizing report outputs without drawing charts. These bars make it easier to visually compare values on the page.
Data Bars are available for numeric report types and can be enabled using the switch with the same name on the toolbar.
When enabled, this feature will display bars in value cells of the report table. The length of the bar in the cell will reflect the magnitude of the value in the cell with respect to the largest value on the page. The higher the value, the longer the bar.