In the current version of RadControls, the desired grouping functionality is not supported by the RadHtmlChart yet. However, such a feature request has already been logged as a PITS item here
, so that you can monitor, comment or raise its priority by voting on it.
If you want to databind the RadHtmlChart to such a datasource, you need to recreate your current logic so that there are separated fields in the datasource that will be referenced by the DataField property of each Series, as it is shown in this
the Telerik team
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