Edit Pivot Table's Source-Table Formulas without Losing Columns in Pivot Tables

Whenever I update any formula within my pivot tables' source data tables, the relevant column is lost from my connected pivot tables upon refresh.

This is an issue partly because it takes a lot of time to remake the pivot tables every time I need to adjust a formula in my source table. However, even if I get to a point where I no longer need to adjust formulas, my users need to be able to overwrite formulas within the source data table.

Help!