I have a workbook with several worksheets (tabs)

The first and main worksheet has eight (8) columns with N rows.

I wish to calculate the number of days between two date values and sum the
results for rows that meet a certain criteria.

Lets use a simple example (so I can understand)

Three columns as follows:

A. Start Date
B. Due Date
C. Criteria

If the word in column C is €œDone€� than calculate the number of days between
A & B and add it to a sum.

A B C
Start Date Due Date Status
01/01/08 01/31/08 Done
02/01/08 04/15/08 Done
03/01/08 05/10/08 Open
04/01/08 06/15/08 Open
05/02/08 06/15/08 Done

Thank you in advance for your help.

Detroit David