The chart type Value over axis shows the values of properties in an observation property structures over its position relative to a specified axis reference system.

The chart can picture observation data from any number of features of any type as long as the observation property structure contains a numeric or quantity property on its topmost level.

If the feature type does not support spatial data for observation the feature will not be drawn.

If the spatial system of a connected feature is not axis or if the spatial system of a connected feature  is Axis but the feature uses another axis or another axis reference system the spatial data will be converted automatically. Note that conversion is not possible under all circumstances. If it is not possible the data will not be shown.