Returns a ChartCharacters object that represents a range of characters within the object text. You can use the ChartCharacters object to format characters within a text string.
The ChartCharacters object is not a collection.
Characters (Start, Length)
Dim ccsCharacters As ChartCharacters
Set ccsCharacters = ActiveDocument.Background.Chart.Axes(1).DisplayUnitLabel.Characters
The following arguments are optional
(Long) - The first character to be returned. If this argument is either 1 or omitted, this property returns a range of characters starting with the first character.
(Long) - The number of characters to be returned. If this argument is omitted, this property returns the remainder of the string (everything after the Start character).