Vince -

You can scale the axis like any other value axes. Double click on the
axis, click on the Scale tab, and enter appropriate values for min, max,
and spacing.

If your numbers are just times (not dates and times), they represent a
fraction of the day since midnight. 6:00 am is 0.25, 12:00 is 0.5, etc.
You could enter all the fractions, but Excel is happy to accept entered
times. Enter 7:00, and Excel will take it. Next time you open the
dialog, it will have been converted into 0.291667.

To get from 7 am one day to 7 am the next, you enter 7:00 as before for
the min. For the max, you need 7 plus 24, so enter 31:00. Use 2:00 or
3:00 for the major spacing.

You will have to add 1 to the data after midnight, because these times
happened on the next day. The easiest way to do this is to type a 1 in
an empty cell and copy it, select the cells to adjust, and use Paste
Special on the Edit menu to paste the values using the operation multiply.

In general it's probably preferable to enter time values as a date time.
If I have data from yesterday at 7:00 to today at 7:00, I can enter
7/20/04 7:00 for the min and 7/21/04 7:00 for the max in the axis scale
dialog, and I never have to worry about adding 1 to some of my data.

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