Smooth Property
True if curve smoothing is turned on for the line chart or scatter chart. Applies only to line and scatter charts. Read/write Boolean.
expression.Smooth
expression Required. An expression that returns one of the objects in the Applies To list.
Example
This example turns on curve smoothing for series one. The example should be run on a 2-D line chart.
myChart.SeriesCollection(1).Smooth = True