Howcan I define date ranges for charts with a drop down box or slider?

Hi,

you have to build your chart with named ranges and have the range definitions created with the OFFSET function

=OFFSET(reference, cols, rows, height, width)

Use the slider output to manipulate the column or row offset.

Jon Peltier has very good instructions on his site

http://peltiertech.com/Excel/Charts/Dynamics.html

hope that helps.