I have the following info setup, I need to be able to sum by customer for
each month. The days represent shipping volumes for each day. This same
setup is repeated through out the spreadsheet until the end of the year. How
or can this be done?

Fri Sat. Mon Tues Wed Thur
SHIP DAY 30-Dec 31-Dec 2-Jan 3-Jan 4-Jan 5-Jan
Toyota 0 0 645
Ford 0 138 150
Honda 1440 1384 1432
Hyundia 660 620 660
Chrysler 0 284 292 288
Nissan 0 120 140 120