EV Licensing and Usage Summary Report -- Invalid Data?

I'm running EV 10.0.4 for Exchange Journaling/Discovery and Exchange Mailbox Archiving. The licensing usage and summary report shows that I am .5 TBs over my limit (.5 TBs is all I currently have archived). I thought that licensing was per active mailbox only, irrespective of size. Can someone please confirm this and maybe see if this is a bug? I'm launching the report from the EV Console\My Directory\Enterprise Server Management.

Thanks.