Please find a copy of the spreadsheet attached, the cells H2 to J9 is the result of populating cells E2 and F2. Hope you gather the layout, columns D and G are only for spacing.

A B C D E F G H I J 1 In Date Out Date NetWorkdays Start Date End Date In Date Out Date NetWorkdays 2 15/08/2011 18/08/2011 4 15/08/2011 28/08/2011 15/08/2011 18/08/2011 4 3 15/08/2011 22/08/2011 6 15/08/2011 22/08/2011 6 4 19/08/2011 29/08/2011 7 19/08/2011 29/08/2011 7 5 20/08/2011 25/08/2011 4 20/08/2011 25/08/2011 4 6 23/08/2011 01/09/2011 8 23/08/2011 01/09/2011 8 7 24/08/2011 27/08/2011 3 24/08/2011 27/08/2011 3 8 27/08/2011 05/09/2011 6 27/08/2011 05/09/2011 6 9 28/08/2011 02/09/2011 5 28/08/2011 02/09/2011 5 10 31/08/2011 04/09/2011 3 11 31/08/2011 06/09/2011 5