As per my understand, in SQL Server 2008 we can display normal and stacked column in same chart. However, after Reporting Services 2008 R2 version, we can only get a single chart type on the data region of the chart.
If you are using SQL Server 2008, we can add another value in the data fields dialog box. Right click the stacked, select Change Chart Type. We can change the value’s Chart Type.
You can refer to the screen shot below:
Since this behavior is by design, I recommend you that submit a wish to the Microsoft Connect at
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