Configures the legend subtitle. The subtitle appears only if the title is specified.
Object
String
To specify only the subtitle's text, assign it directly to this property. Otherwise, set this property to an object with the text and other fields specified.
Specifies the legend subtitle's font properties.
The following code sample illustrates how to set this property:
Specifies the distance between the legend's title and subtitle in pixels.
Number
Specifies the subtitle's text.