How are your tables set up? Is the data from the to layouts in the same table or different tables?
It looks like you could do this if you carefully merge your data into the same table so that the two "levels" are represented by two different records in the same table. I can't say much more without kowing a lot more about how you've set up your database. It may well be that you need several more tables than you have right now linked in relationships to bring together the report you want.
They are in different tables, and pull in data from many others. I seem to have made some headway by simply importing one table into the other via the "import files" option. Perhaps not the best way but all 142 unique values now appear in the one table