Hi David,

Jon Peltier has a site that mentioned about dynamic charts which I find
useful and you might want to check this out.
http://peltiertech.com/Excel/Charts/Dynamics.html
You should find your solution there. You might need to modified a bit to
suit what you really wants (at least that is what I do).

"David Taylor" wrote:

I am trying to add a trendline to a process variable on a line-chart and use
it to predict when remedial action is required. When the data parameter is
reset, the trendline automatically takes in this new set of figures and
attaches it to the previous, giving a totally skewed analysis. Is there any
way that I can select only some of the data to trend? Then as the reset data
grows, only to select the new series from the process?
Thanks