Unfortunately this report is hard coded into the core of the app and not that easy for us to change. In the meantime, the workaround I used with retailers for years was to customise the item listing report, and then export it to excel (so you could add more space and a line for the counts). I know it's a bit of extra work, but does allow department (item parent) filtering etc.. TIP: You can memorise the same report over and over, so I personally created a group of memorised reports, and then memorised different versions for each department. Using the Process multiple report function you can then run them together, so it didn't take too much time, even for 50 or so departments.
Unfortunately this report is hard coded into the core of the app and not that easy for us to change. In the meantime, the workaround I used with retailers for years was to customise the item listing report, and then export it to excel (so you could add more space and a line for the counts). I know it's a bit of extra work, but does allow department (item parent) filtering etc.. TIP: You can memorise the same report over and over, so I personally created a group of memorised reports, and then memorised different versions for each department. Using the Process multiple report function you can then run them together, so it didn't take too much time, even for 50 or so departments.