Stacked Area charts are displayed with several NAreaSeries objects. The MultiAreaMode property of the first area series must be set to MultiAreaMode.Series. The MultiAreaMode property of the subsequent area series must be set to MultiAreaMode.Stacked. The following example demonstrates how to create a stack area chart with two stacks:

// obtain a reference to the Cartesian chart that is created by default
NCartesianChart chart = (NCartesianChart)chartControl.Charts[0];

// create two area series
NAreaSeries area1 = (NAreaSeries)chart.Series.Add(SeriesType.Area);
NAreaSeries area2 = (NAreaSeries)chart.Series.Add(SeriesType.Area);

// stack the second area over the first one
area1.MultiAreaMode = MultiAreaMode.Series;
area2.MultiAreaMode = MultiAreaMode.Stacked;

' obtain a reference to the Cartesian chart that is created by default
Dim chart As NCartesianChart = chartControl.Charts(0)

' create two area series
Dim area1 As NAreaSeries = chart.Series.Add(SeriesType.Area)
Dim area2 As NAreaSeries = chart.Series.Add(SeriesType.Area)

' stack the second area over the first one
area1.MultiAreaMode = MultiAreaMode.Series
area2.MultiAreaMode = MultiAreaMode.Stacked

If you want to create a second stacked area with two stacks behind the stack area created in the previous sample you have to add the following code:

NAreaSeries area4 = (NAreaSeries)chart.Series.Add(SeriesType.Area);
NAreaSeries area5 = (NAreaSeries)chart.Series.Add(SeriesType.Area);
area4.MultiAreaMode = MultiAreaMode.Series;
area5.MultiAreaMode = MultiAreaMode.Stacked;

Dim area4 As NAreaSeries = chart.Series.Add(SeriesType.Area)
Dim area5 As NAreaSeries = chart.Series.Add(SeriesType.Area)
area4.MultiAreaMode = MultiAreaMode.Series
area5.MultiAreaMode = MultiAreaMode.Stacked

By default stacked areas treat negative values with their absolute values. In order to use negative stack values you need to explicitly enable them by setting the AllowNegativeStackValues property to true:

The following formatting commands inherited from the NSeries class have different meaning when an area series is stacked:

<total> - displays the absolute sum of the values in the current stack.
<cumulative> - displays the sum of the values up to the current stack value.
<percent> - displays the percent contribution of the value to the total pile sum.