Returns or sets the period for the moving-average trendline. Read/write Long.
Example
This example sets the period for the moving-average trendline on Chart1. The example should be run on a 2-D column chart with a single series that contains 10 data points and a moving-average trendline.
With Charts("Chart1").SeriesCollection(1).Trendlines(1)
If .Type = xlMovingAvg Then .Period = 5
End With