You can determine which chart element is selected using the Selection
object, but it's tedious to do this to get more than one selection, because
you have to make the user stop, select something else. then click something
to continue the code.

You can also use chart events to respond to mouse actions in the chart. It's
a bit tricky, especially if you've done little programming, but here's a
reasonably straightforward tutorial:

http://www.computorcompanion.com/LPMArticle.asp?ID=221

I've used this technique to do much the same as you, let the user easily
select the first and last point for detailed analysis.

- Jon
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Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
Peltier Technical Services, Inc. - http://PeltierTech.com
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