Right click on the axis and the select "Format Axis". You can also do this for the Major and Minor gridlines.
If you want to create a specially formatted line within the chart, you can add another data series using points to creat the line you desire, and foprmat it as you need.
Regards,
Mark Graesser
(e-mail address removed)
----- boyesee wrote: -----
Is there a way to customize a grid line on one of the
axes? I am using excel 2000.