SeriesCollection Method
Returns an object that represents either a single series (a Series object) or a collection of all the series (a SeriesCollection collection) in the chart or chart group.
expression.SeriesCollection(Index)
expression Required. An expression that returns a Chart or ChartGroup object.
Index Optional Variant. The name or number of the series.
Example
This example turns on data labels for series one in Chart1.
Charts("Chart1").SeriesCollection(1).HasDataLabels = True