CRM 2016 Report Wizard - how to "collapse" detail records, printing a report consisting of only groupings?

I have captured Sales data (product group, invoice date, invoice amount) in a custom entity.  I created a report that groups by Product Group, subgroups by Invoice Date (monthly).  Then I have created a "count" field to show how many invoices fall within that Product Group / Month, and have that as my 3rd subgroup.   All I need is the count.  I do not want to see the 40 or 50+ invoice records that make up the count.  Can this be accomplished within Report Wizard, without custom programming?