Excell graphing
 

I am trying to determine the Excel formula for total of pieces, in a given
week, in a given area that are incorrect.

Date Area Incorrect Pieces Week 1 Week 2 Week 3
1/1/2007 Area #1 10 Area #1
1/15/2007 Area #1 15 Area #2
1/16/2007 Area #1 25 Area #3
1/20/2007 Area #2 10
1/22/2007 Area #3 5


Thoughts?