I am sorry to say that data source grouping functionality and Stacked Bar 100% Charts are supported only by the obsolete RadChart control and not by the RadHtmlChart. What I can suggest is that you:
- Either group the data source manually and pass it to the RadHtmlChart. Such an example with a DataTable data source is illustrated in this forum thread. Once you bind the chart to the grouped data source, you can stack the series in separate clusters as illustrated in this online demo. You may also raise the priority of this feedback item by voting on it, so that once implemented it would allow you to use stacked 100% series in RadHtmlChart too.
- Or use the obsolete RadChart control with stacked bar 100% series and its grouping functionality.
More information on the pros and cons of both charts can be found in RadHtmlChart vs. RadChart, round 2. Which one is right for me? blog post. You may also useful the Migrating Functionalities - Features and Series Types Parity help article that illustrates the known limitations of the features and series types in RadHtmlChart when migrating from RadChart.
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