Misleading
I always find these figures misleading - EMC, Netapp, IBM and HP all sell storage which comes with software to manage the storage. Is it storage software? Well yes it is but it is only software for their disk so it is then difficult to do a true comparison against Symantec, Commvault and other software companies.
I would be much more interested in seeing storage software which is not a prerequisite of the arrays broken out so we can see the figures for things like backup, archiving, storage agnostic replication and so on where the pure play software vendors are not trying to "compete" against proprietary storage software sold (or given away) with disk.