An addendum to my question below: Additionally, if I use "Automatic" or
"Category" for the X-axis, then all the dates are plotted at equal distances
from each other rather than being scaled according to the time between them.
Again, the end result is that I need to evaluate the rate of change of these
values over time, so any way that I can do that either by chart or otherwise
will help me. thanks, Ronan

"Ronan" wrote:

I have sets of data that have a date with a corresponding numerical value in
number format with one decimal. When I try to plot them on a line chart with
a time-scale axis, Excel defaults to putting my points between 1/1/1900 and
1/20/1900. If I change the dates, then all my points end up nearly
vertically on the y-axis and do not correspond to the dates on the x-axis,
even though the point will indicate the correct date if you point to it with
the mouse. My final goal is to evaluate the rate of change in the values,
which I hope to do by looking at the average slope of the line. Thanks for
your help.