Data Bars can be used to compare numbers where you need to present information in a table, but a trend or pattern is more easily seen visually. They are a bit like a mini Bar Chart in a worksheet cell.
Data Bars can be created from positive or negative numbers, you can specify the scale of the bars and you can choose to show only the bar (and hide the numbers).
Note: This tutorial applies to Microsoft Excel 2016. But you should be able to take the ideas shown here and get similar results in earlier versions of the software (where the feature described is available).
Creating Data Bars
Select a range of cells that you want to turn into Data Bars.
Go to the Home tab and select Conditional Formatting, Data Bars.
From the pop-out menu, select the style that you prefer.
(There are 12 colours available, six as gradients, six solid. I prefer the solid options as I believe they are easier for the reader to interpret.)
Adding bars with hidden numbers
Another option you have, is to show the bars only by hiding the numbers in the formatted cells.
When I do this, I like to duplicate the numbers by using a simple formula.
Then, I apply data bar formatting to this second column of numbers.
Next, from the Ribbon Home tab, I select Conditional Formatting, Manage Rules.
After selecting the Data Bar rule (if there is more than one rule), I select Edit Rule, and click the Show Bar Only check box.
Clicking OK a couple of times get you the final result.
Try it out the next time you need a little visual pop added to your tables.