Thanks for asking. Unfortunately, our RadChart does not support such functionality. You can set the label to appear to the right of the point like this:
RadChart1.Series.Appearance.LabelAppearance.Position.AlignedPosition = AlignedPositions.Right;
RadChart1.Series.Appearance.LabelAppearance.LabelLocation = ItemLabelLocation.Inside;
Still, the line may go up or down and there is no way to force the label to stay on the line.
the Telerik team
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