i'll try to explain best i can....
i have 3 colums, first and second are put in and the third is the difference
between them. then on the bottom, i have the averages. i know how to do the
subtraction, but for the other rows below keep showing "0" even though and
the averages are now correct. how can i keep that column to automatically
show the difference without always having the zero there and not having to
always put that function in that box.

here is what i looks like

# DATE COURSE SCORE PAR (+/-)
1 04/03/10 49 37 12
2 04/03/10 43 34 9
3 04/19/10 44 36 8
4 0
5 0
6 0
7 0
8 0
9 0
0

AVERAGE 45.33 35.67 1.38