AFAIK, NetBackup itself does not have a report or CLI function to report this. You may be able to script something to determine how much time a drive is spent 'in use', but it would be very difficult to determine how much data a tape drive moved for any given time period, from purely a NetBackup server perspective.
I believe that OpsCenter has tape drive utilization reports which may be of some use to you. OpsCenter, the basic installtion type (un-licensed), is free to use - i.e. not the licensed OpsCenter Analytics installation type.
