Thanks Mak
I have gone this road. The issue seems to come from the 0s for each var.
So if you build a table of doc numbers, then add each variable, you see the 1,0s for each column..but..its a drill down, so for a doc with 2 groups you get 3 rows, 1,0, then 0,1, then 0,0
this means you never get get a sceanrio where grpa =1 and grpb =1.
still hunting...
jim
