use a pivot table
simple as pie
jerry


>A B
>
>1/1/2006 152.3
>
>3/1/2006 156.2
>
>8/1/2006 186.1
>
>5/2/2006 185.2
>
>19/2/2006 145.2
>
>.. ..
>
>
>
>I need to sum from all data on a monthly base.
>
>Jan : ..
>
>Feb : ...
>
>March : ...