Pointing to plotted points to see the data

I periodically make a x,y scatter chart using dates for x
and a number for y, like this:
x y
8/12 213
8/13 254
8/14 198
etc.

Previously, when I would use the mouse to point at a
point on the chart, Excel would display the date and the
number (e.g. 8/13,254). Now, with my most recent chart,
Excel displays a sequential number instead of the date
(e.g. 2,254). Why has it changed? And where in Excel
can you specify how the x value is to be displayed?

There's a slight difference in how Excel displays point value for XY
Scatter charts and Line charts.

Line:
Series "y" Point "13-Aug"
Value: 254

Scatter:
Series "y" Point "13-Aug"
(13-Aug, 254)

The 13-Aug matches the date format in my cells; your 8/13 matches your
date format. If this the difference you're seeing isn't that between
Line and Scatter, check whether you have X values defined for the
series. If the series formula looks like this:

=SERIES(Sheet1!$C$5,Sheet1!$B$6:$B$8,Sheet1!$C$6:$ C$8,1)

you do, but if it looks like this:

=SERIES(Sheet1!$C$5,,Sheet1!$C$6:$C$8,1)

you don't (note the empty field between the two commas). If Excel
doesn't have explicit X values, it just counts the points and uses those
numbers (1,2,3,...). In this case the chart tips look like

Line:
Series "y" Point 2
Value: 254

Scatter:
Series "y" Point 2
(2, 254)

If you go to Options on the Tools menu, and select the Chart tab, you
see two checkboxes under the heading Chart Tips. In mine, both Show
Names and Show Values are checked, so my labels have a two-line pop up.
If I uncheck the names checkbox, I get (13-Aug, 254) if the X values are
given, and (2, 254) if they are not. You cannot tell Excel to enter a 2
in the pop up if there is a date in the X values.

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

wrote:
I periodically make a x,y scatter chart using dates for x
and a number for y, like this:
x y
8/12 213
8/13 254
8/14 198
etc.

Previously, when I would use the mouse to point at a
point on the chart, Excel would display the date and the
number (e.g. 8/13,254). Now, with my most recent chart,
Excel displays a sequential number instead of the date
(e.g. 2,254). Why has it changed? And where in Excel
can you specify how the x value is to be displayed?