If the group names are always the same, you can hard-code them into a text object in the report header.  However, if the group names will changed based on data, you'll have to use a subreport.  The subreport will use the same tables as the main report.  If your main report uses any parameters to filter data, you'll want to link the subreport on those parameters but you don't need any other links to data in the report.

 

Generally I try to avoid subreports, but displaying what is essentially "summary" data at the beginning of a report is a place where that's the only way to get what you want.

 

-Dell