Use Conditional Formatting with the the formulas:
=$M$3>=80
and
=$M$3<80

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HTH
Sandy
In Perth, the ancient capital of Scotland
and the crowning place of kings
sandymann2@mailinator.com
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>I have a command using the IF function that is as follows:
> =IF(M3>=80,"YES","NO")
[quoted text clipped - 3 lines]
> code
> that will do this.