Try naming your data range using the offset function; e.g., when you create
the name for your first series, the reference will be something like "=offset
($g$3,0,0,$g$1,1)". In this example, cell "g1" will be a formula that
determines how long the series is; one way to do this is to use a match
function (e.g., "=match("",g3:g30,0)-1"). Next, in your chart, use the
dynamic name you created to define your series. You'll need to make sure
that your X-axis series is also defined in the same way.

Good Luck.


>Second, the soure series are named ranges that are not always totally filled
>with data. How do I specify that the boundary of the range to take is the
>last cell that contains data?
>Thanks a lot