One way:

=SUM(A1:INDEX(A1:L1,n))

Where n = your variable. N can be a cell reference or it can be calculated:

A2 = 7

=SUM(A1:INDEX(A1:L1,A1))

=SUM(A1:INDEX(A1:L1,MONTH(NOW())))

Both of the above formulas translate to:

=SUM(A1:G1)

--
Biff
Microsoft Excel MVP


"Man" wrote in message
...
I need to sum budget from month 1 to month "N", where "N" is a variable
that
changes each month, but I don't want to change the sum formula, only the
variable that represents the month.