How to Use Net Activity in Auto-Submit Rules?

When creating an auto-submit rule for a quarterly rec, we would like to use the Net Activity balance as one of the rule conditions. However, Net Activity does not appear in the drop-down of options. As I understand, Period Activity only refers to monthly activity, so if you have a quarterly rec, Period Activity would not properly reflect the quarterly activity of the rec, so it cannot be used in the rule. Since Net Activity reflects the quarterly activity, is there a workaround so Net Activity can be used as a rule condition?

Thank you.

Steve