ChartGroupDropLines
Border
Represents the drop lines in a chart group. Drop lines connect the points in the chart with the x-axis. Only line and area chart groups can have drop lines. This object isn’t a collection. There’s no object that represents a single drop line; you either have drop lines turned on for all points in a chart group or you have them turned off.
Using the DropLines Object
Use the DropLines property to return the DropLines object. The following example turns on drop lines for chart group one in embedded chart one and then sets the drop line color to red.
Worksheets("sheet1").ChartObjects(1).Activate
ActiveChart.ChartGroups(1).HasDropLines = True
ActiveChart.ChartGroups(1).DropLines.Border.ColorIndex = 3
Remarks
If the HasDropLines property is False, most properties of the DropLines object are disabled.