How does this excel color coding work

This is the file:

This is a screenshot:

This is a screenshot of the first tab/sheet:

I would like to know how the color coding works here. I would like to use it in another file and also maybe edit the color coding in this file.

How were the circles created and inserted? How to setup the conditions for the colors? How to make it change?

There is a box at the top left called "Thresholds" and the circles themselves are used right from column N onwards. These are the two relevant spots on the sheet I guess.
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Richard DanekeTrainerCommented:
The spreadsheet is using Conditional Formatting for the cells and the circles are called Icon Sets.  

Once the Icon Sets are placed in a cell, the Conditional Formatting, Manage Rules... provides options for setting the thresholds for circles to change colors.

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Microsoft Excel

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