Start with New Report/Account/Create
- Change the time period to 'All Time' and accounts to 'All Accounts'
- Change your report type to 'Matrix'
- Search for the level of the hierarchy you want to roll up to - we'll use DU for this example - and drag the 'DU Company Name' field into the filters. Here put an equation that the field 'does not equal' blank (leave cell blank and hit 'ok')
- Drag this 'DU Company Name' field again into the left-hand column of the matrix report to create a row grouping:
Save and run report: