Cannot choose Additional Values when editing in Select Data of a c

[Margie]

In my chart, each month I have to add another set of data. Usually, I go to
Select Data, and edit the Series by Contol + select the newest cell. This
month (October), when I try to Control+Select, all the previously chosen
cells are deselected.

It's almost as if this method works for 9 entries, but when I try to do 10
(October being the 10th month), it doesn't allow me to add that many values.

How can I easily add my 10th month (and 11th & 12th) of data to a chart?

 

[Jon Peltier]

The method works until the amount of text required to list the data
exceeds about 255 characters (actually somewhat fewer characters). The
text is long, because the sheet reference is repeated for each point:

Sheet1!$D$7,Sheet1!$D$9,Sheet1!$D$11,Sheet1!$D$13,Sheet1!$D$15

I often tell people that they can spend five minutes with the data, or
struggle for five hours with the chart. Spend your five minutes to
arrange your data so that the chart uses contiguous regions. You're
going to say, "but this is how my data is arranged." To which I'll
reply, "You're not thinking outside the box, rearrange the data." Use a
second range that's appropriately arranged for the chart, which links to
the range which is arranged for some purpose, but not for the chart.

- Jon