On a 2-D chart, returns an object that represents either a single column chart group (a ChartGroup object, Syntax 1) or a collection of the column chart groups (a ChartGroups collection, Syntax 2).
Syntax 1
expression.ColumnGroups(Index)
Syntax 2
expression.ColumnGroups
expression Required. An expression that returns a Chart object.
Index Optional Variant. Specifies the chart group.