DescriptionReturns a CategoryAxis object representing the chart's category values on the Z axis.
In excel, this axis line can be accessed and manipulated by going to "Chart Tools"->"Layout"->"Axes"->"Depth Axis". The Z Category Axis is also known as the series axis in some cases.
This property is never null and the returned object can always be modified. But changes made to this property will only be reflected in the resulting file if the chart type is an Area3D, Column3D, Line3D or the chart is any kind of surface chart.
By default, the ZCategoryAxis will point to an object that's flagged as visible and has all the default axis settings.