You essentially enter logic such that if X is, say, >= Y, make the cell green. If X==Y, cell is yellow. If X<Y, cell is red.

I've also gotten alot of run out of knowing how to name a range of values and then using countif() to find the certain values in that range.

For instance, if I've got 10 values in column A of Sheet1 that I need to find amongst 5000 values in another tab in Sheet 2 of the spreadsheet, I'll name the large range of values "MyRange".

Then in column B of Sheet1, I'll put =countif(MyRange, A1)>0 . The ">0" at the end changes the countif into a True/False statement.

So if A1 is in the range of 5000 values in "MyRange", B1 will be "True". If not, it'll be false.

Autofill that function for all 10 entries and I've quickly determined whether any entry in column A is in "MyRange".

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