I have an Excel spreadsheed of my service calls entered by date and including
columns for labor, parts, tax and total. I can select all the entries in any
given column and then click on the sigma icon to give me a grand total for
that column but what I really need is the ability to have subtotals for each
column at the end of each month. I am sure there is a way to do this, but I
don't know how. Any help would be appreciated.

Thanks

Ted