Hi,

a pivot table would probably be the best way to sum up the data by month and other criteria, like line of business.

Based on the data sample you provided you can use a formula like

=SUMPRODUCT((MONTH(A3:A12=MONTH(H1))*(C3:C12="Shipping")*D3:D12))

where H1 holds a date, to sum up all shipping amounts for a specific month.

hth