Thank you for writing.
Please refer to the following help article which demonstrates a sample
example how to setup drill down chart: http://docs.telerik.com/devtools/winforms/chartview/features/drill-down
In addition, in our Demo application you can find a fully functional example: Demo application >> ChartView >> Drill-down
example. You can find the Demo application in the installation folder: C:\Program Files (x86)\Telerik\UI for WinForms Q2 2016\Examples\QuickStart\Bin
I hope this information helps. Should you have further questions I would be glad to help.
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Check out the Windows Forms project converter, which aids the conversion process from standard Windows Forms applications written in C# or VB to Telerik UI for WinForms.For more information check out this blog post
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