Hi,
(looks like my previous posting was lost . . . . ?)

thanks to the help from this forum (Roger G. !),
==for using the same graph, for various worksheets==,
I am now using a named range called: GraphRange, with a value of:
=INDIRECT(INDEX(Graphs!$A$1:$A$20,Graphs!$B$1)&"!$ F$6:$F$10")
where the worksheet names are listed in A1:A20; the worksheet I want
to use is listed in B1; the relevant data is in e.g. F6:F10.

This works however only partially: when I use "GraphRange" in the
field [Chart data range], when selecting data for the graph, the
formula/value -as described above- is replaced by the outcome of
the formula. So when I change the content of B1, the graph does NOT
change (but when entering "GraphRange" again in [Chart data range] the
graph does change . . . .
Q: How can I keep the formula/value (GraphChange) in the [Chart data range]
field (so that the graph changes with the change of content in B1 ???
(Remark: I have B1 changing through selection via 'Combo Box' from A1:A20)

Thanks in advance,

Paul