Looking at your example, I am wondering if it is because you have numbers in multiple groups. For example - the number 15 would appear in the first group and the second group because you have <=. Maybe you want your formula to be:
if {@differtimeinMIN} >= 0 and {@differtimeinMIN} < 15 then
1
else
0
You might try running your report for the first group only. Check your counts and make sure they are correct. Add the code for the second group and again, make sure your counts are correct. Continue with all the groups. That might make it easier to debug the problem.
Edited by JohnT - 21 Oct 2008 at 6:40am