ChartGroup Object (PowerPoint)
Represents one or more series plotted in a chart with the same format.
A chart contains one or more chart groups, each chart group contains one or more Series objects, and each series contains one or more Points objects. For example, a single chart might contain both a line chart group, which contains all the series plotted with the line chart format, and a bar chart group, which contains all the series plotted with the bar chart format. The ChartGroup object is a member of the ChartGroups collection.
Use ChartGroups(Index), where index is the chart group index number, to return a single ChartGroup object.
Although the following code applies to Microsoft Word, you can readily modify it to apply to PowerPoint.
The following example adds drop lines to the first chart group of the first chart in the active document.