How can I sort by total field? I mean, I am talking about Interactive sort, and I want to sort not by the single field but by total filed of the group (not the general total but the partial total(*)).
Exmpl:
one one.one 10
one.two 20
TOTAL 30 <--(*)
two two.one 40
TOTAL 40 <--(*)
TOTAL 70
Thank You!!!