Conditional Formatting based on adjacent cells in a Pivot Table

When i export data from our database into an excel spreadsheet, i create a pivot table that allows better sorting of the financials that i can then share with individual employees. I utilize slicers to do this as well.

What i'm trying to do is highlight cells in the Total Cost column "C" that are greater in value than the amount in the Revenue Remaining column "B". I have tried "Conditional Formatting", starting a "New Rule" and selecting "Use a formula to determine which cells to format" and tried highlighting cells i want formatted with the formula: =$C$5:$C$20>$B$5:$B$20 and then adding a yellow highlight to the cell if it matches that criteria, but no luck.

Thank you in advance for your help in this matter.