You have opened this thread with the old RadChart as a product. We suggest you do not use it, but use the new ChartView instead. It is much faster, it resolves many of the limitations of the old charting component, it is very flexible and easy to set up.
It seems that you require grouping functionality, where a single items source is grouped into several objects, where each object has a Key the Description, and an associated list of items. The chartview does not provide grouoing capabilities out-of-the-box.
I think that the best way to go here is to declare an additional property in you view model SeriesModels which hold the grouped data. You can then use a SeriesProvider which will dynamically create as many series as SeriesModels you have.
QSF SeriesProvider demo
(one of many examples that uses the SeriesProvider)
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