My worksheet has 50 rows showing sales for each book. It has 39 columns - 3
for each month - budget, actual and diff - and 3 more columns for YTD. They
are like this:
Jan-Budget Jan-Actual Jan-Diff Feb-Budget Feb-Actual Feb-Diff
etc.

I have budgets for each month for each book on the worksheet already. I
update it monthly to enter actual sales for the month. I want the YTD-Budget
column to only sum up months that have actual activities so I can do a fair
comparison with YTD-Actual.

I tried to create a formula that sums up the budget columns for months where
Total Actual for the month is < 0. But I didnt' get it right.

I'd appreciate if you can help me with that. Thanks in advance!