There are two options to change this behavior;
1. Decrease the number of labels by setting theradChart1.PlotArea.XAxis.LabelStep
, but since you bind the labels to the datasource, that will not do the trick (I just mention this option for you to have in mind in other cases).
2. The other option (the only one applicable in your case
) is to rotate the labels, so that they take less space:
radChart1.PlotArea.XAxis.Appearance.LabelAppearance.RotationAngle = -90;
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