Combined and Summary

[magic_ma]

Hi all


how can i make my sales details Cell B4 as 2010-01-01 to 2010-01-09, C4 with 01/10 - 01/16, D4 with 01/17 - 01/23 and E4 from 01/24 - 01/31.

If i select interval to be 7 days, then each column will auto adjust to 7 days which i don't want as the 1st week i need define to 01/01 - 01/09.

Please advice and your help is great appreciated.