The new features in Conditional Formatting can be used to identify and highlight important trends and exceptions in your data. You can choose from Text changes or use the new Heat Maps, Data bars, and Icons.
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Select the required data column or row
Click on Conditional Formatting
Select from Data Bars or Icons
Pick the icon that communicates your message
You will have a live Preview of the effect on your data
Click Ok
To clear the formatting
Select the data
Click on Conditional Formatting
Clear Rules
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Source: Really Useful