True if the minor unit for the specified axis is set to be determined automatically. The default value is True. You should use this property only for value axes. Read/write Boolean.
expression.HasAutoMinorUnit
expression Required. An expression that returns a ChAxis object.
Example
This example sets the minor unit for the specified axis to increments of 500 if the unit is currently set to be determined automatically.
Sub SetMinorUnit()
Dim chConstants
Dim axs
Set chConstants = ChartSpace1.Constants
Set axs = ChartSpace1.Charts(0).Axes(chConstants.chAxisPositionValue)
If axs.HasAutoMinorUnit Then axs.MinorUnit = 500
End Sub