In Formula for GF2, add a line at the top:
shared numbervar sumGF2;
local numbervar GF2;
set GF2 = to your original formula value then to update the summary
sumGF2 := sumGF2 + GF2;
GF2 //Crystal prints the last value that it 'sees'
Create a new formula, say, summaryGF2 and all that it would contain is:
shared numbervar sumGF2
create a new formula, I usually call Reset
shared numbervar sumGF2 := 0
"" //I suppress the out put so the user can't see it.
reset would go probably in GF1 header, so every time it changed, the summary would start over, the summaryGF2 would go in the GF1 footer where you want the summary to be displayed.
Hope this helped