Indeed, the data will need to be grouped accordingly in order to achieve this design.
With that being said, the popular look and feel of the calendars is nothing more than a Crosstab presentation of the dates in a period of time. Since the time is a well-defined dimension using the Telerik Reporting's Table item to implement a calendar presentation is straightforward and is illustrated in the following blog post: Creating a Calendar Report with Telerik Reporting.
I have upgraded the project for your convenience. To run it successfully, you would need to build the project and run the Upgrade Wizard to add the required Telerik Reporting references.
Let me know if you have any other questions.
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