Thanks for the post.
You can create two new TO's and link them in by both po_no AND po_status. One TO would link by po_no AND link po_status to a global field that is always "accept" while the second TO would link to po_no and a second global field that always has "cancel".
In this way, you can portal the "accepts" in and do a
po_total=Sum(vot21accept:: po_amount) and a separate
po_cancel_total = Sum(vot21cancel:: po_amount)
This would update automatically by linking or unlinking the records from the Table Occurrences.
Is this what you are looking for?
Yup, I got it, TQ