Set the position of each [SeriesDataLabel] using the [DataLabelPlacementType] enum.
Only certain combinations of Placement types and chart types go together. Any invalid combinations will result in an ArgumentException.

{align:center}
|| || Area || Bar || Bubble || Column || Doughnut || Line || Pie || Radar || Scatter ||
| *Above* | | |{center} (/) {center}| | |{center} (/) {center}| | |{center} (/) {center}|
| *Auto* | | | | | | |{center} (/) {center}| | |
| *Below* | | |{center} (/) {center}| | |{center} (/) {center}| | |{center} (/) {center}|
| *Center* | |{center} (/) {center}|{center} (/) {center}|{center} (/) {center}| |{center} (/) {center}|{center} (/) {center}| |{center} (/) {center}|
| *Default* | |{center} (/) {center}|{center} (/) {center}|{center} (/) {center}| |{center} (/) {center}|{center} (/) {center}| |{center} (/) {center}|
| *InsideBase* | |{center} (/) {center}| |{center} (/) {center}| | | | | |
| *InsideEnd* | |{center} (/) {center}| |{center} (/) {center}| | |{center} (/) {center}| | |
| *Left* | | |{center} (/) {center}| | |{center} (/) {center}| | |{center} (/) {center}|
| *MovedByUser* |{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|{center} (/) {center}|
| *Right* | | |{center} (/) {center}| | |{center} (/) {center}| | |{center} (/) {center}|
| *OutsideEnd* | |{center} (/) {center}| |{center} (/) {center}| | |{center} (/) {center}| | |

If the X or Y property of the DataLabel are set, then the DataLabelPlacement is also set to 'MovedByUser'.
{align}

//--- Create chart
Chart chart = ws.Charts.CreateChart(ChartType.Column.Stacked, ws.CreateAnchor(10, 0, 0, 0));

//--- Create data series
Series series = chart.SeriesCollection.CreateSeries("A1:A10");

//--- Set the data label position for the first SeriesDataLabel to OutsideEnd
series[0].Label.DataLabelPlacement = DataLabelPlacementType.OutsideEnd;

'--- Create chart
Dim chart As Chart = ws.Charts.CreateChart(ChartType.Column.Stacked, ws.CreateAnchor(10, 0, 0, 0))

'--- Create data series
Dim series As Series = chart.SeriesCollection.CreateSeries("A1:A10")

'--- Set the data label position for the first SeriesDataLabel to OutsideEnd
series(0).Label.DataLabelPlacement = DataLabelPlacementType.OutsideEnd