Chart.ShowDataLabelsOverMaximum (PowerPoint)
Returns or sets a value that indicates whether to show the data labels when the value is greater than the maximum value on the value axis.
If you change the value axis in such a way that it becomes smaller than the size of the data points, you can use this property to set a value that indicates whether to show the data labels. This property applies to 2D charts only.
ActiveWindow.RangeFromPoint.Chart.ShowDataLabelsOverMaximum = True