As part of a dashboard data visualization element, I would like to plot the average of the difference between two fields in a record (i.e. `AVG(table.fieldB - table.fieldA)`) but have struggled to find something that doesn't seem overly complicated for such a simple task. (One route I have explored is indicator sources and scripts, but that feels like an awful lot of work.) Is there something I am missing? Have you had to do this before? Thanks for any help.
