Dear experts,

I've a table which column B to column M are months of 2008, e.g. B1 = Jan
08, C1 = Feb 08 and so forth. Then, in row 10, 15, 22, 35, 42........up to
372 are rows for totals of different departments (the number of rows for each
department are not even). My question is, if I want to sum up all
departments' totals of any month (say only April), are there any best and
quickest ways (formula) to do it. If yes, please kindly advise.

Thanks in advance.