You can't put any functions in a SERIES formula, just links or static
values.

The best way to handle this is with a helper row/column. For example, your Y
values are in E2:HG2. Put your multiplier into cell C3, select E3:HG3 with
E3 as the active cell, and enter this formula:

=$C3*E$2

then hold Ctrl and press Enter. Use row 3 instead of row 2 in the chart.
Changing the value in C3 will change the values in the chart automatically.
It's easy to understand, easy to see where an error may have crept in, and
in Excel 2003 and earlier it's very fast. Excel 2007 has some performance
issues with charts that have more than a trivial number of points, but the
SP2 (just out) is supposed to improve this.

- Jon
-------
Jon Peltier, Microsoft Excel MVP
Peltier Technical Services, Inc.
http://PeltierTech.com/WordPress/
_______


"Nick H" wrote in message
...
My client would like to be able to adjust all the values in a chart,
that is based on a large set of data, by some percentage depending on
various scenarios.

Is it possible to do this directly in the series formula? E.g.
something like...

=SERIES(Sheet1!$D$2,Sheet1!$E$1:$HG$1,Sheet1!$E$2: $HG$2*MULTIPLIER,1)

...where MULTIPLIER is a reference to a cell containing the percentage
variance.

Preempting the alternative suggestions of recalculating via VBA or
placing a formula in each datasource cell that calculates the product
of the multiplier and its original value - can anyone suggest which
method might be quicker on a range of 40,000 cells?

Br, Nick H