Format Rule - Formula to Highlight date range

[Dean_Manning]

Hi All,

I would like to color text based on a date range in our App. I can get the items to highlight in the App based on the formula for a specific date example - [Next Test Due]=Today()+21

This highlights with the color on that specific date.

What would be the formula to put a date range between 1 & 21 days of my required test date to highlight that the item is coming up due for test in the next 21 days.

Thanks Dean.