Hi @James Stone In my opinion, the Excel formula can be created as a measure in Power Pivot directly.
Since the Q&A forum is responsible for general Excel usage questions, for measures of Power Pivot, you can go to Microsoft Fabric Community. (For better help, you may add a sample in your post.)
https://community.fabric.microsoft.com/t5/DAX-Commands-and-Tips/bd-p/DAXCommands
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