DataLabel.Separator (Excel)

Sets or returns a Variant representing the separator used for the data labels on a chart.

If you use a string, you will get a string as the separator. If you use xlDataLabelSeparatorDefault (= 1) (see the XlDataLabelSeparator enumeration), you will get the default data label separator, which is either a comma or a newline, depending on the data label. When a value of "1" is returned, it indicates that the user has not changed the default separator, which is a comma ",". You can also pass a value of "1" to change the separator back to the default separator. The chart must first be active before you can access the data labels programmatically; otherwise, a run-time error occurs.

ActiveCell.Width(1).DataLabel.Separator = ";"