Custom Colors on Number Fields

We have fields that calculated for numbers to display in reports. Right now, I cannot set a range of numbers to a specific color that is not a scorecard.

IE I have a field that calculates number of months since an update was made. I want to display the number of accounts by the number of months not updated, and if the number is greater than 2 to have a red as that is considered too long since update. Right now it is defaulting to a green - which is counter intuitive to what that actually means