Change Text Color Based on Date

I have this pick list report that gives a list of items on an order. On this report we also have multiple tag numbers that will allow us to see which item is the oldest and basically tells us which on to pick. Ive had it sort those tags in each section by the date they were manufactured and that works. What I'm trying to do now is change the text color of that oldest item to red so I can always tell our employees to pick the item in red. I have written a script and it does highlight the oldest in red but it does do it per section. It does it as a whole which means some parts do get highlighed because their date is newer than a date in another section. Below is my script. Can you help me correct this?

If ({PickList.OrderMaterialAvailable__Date_Posted} = minimum({PickList.OrderMaterialAvailable__Date_Posted}))
then crRed else 0