Parallel Period function in Key Value element

[Jazzman]

Hello, I'm trying to display a live calculated change from last year's parallel month in a Key Value element. The data element works as expected in a table without the filter applied but doesn't display the expected values when assigned to a Key Value object. I think the problem is that the ParallelPeriod function doesn't recognize the report filter as the source for the current month value but I can't find any documentation on how to fix this. Any recommendations?