There is a known bug with usage figures on the Superhub.
Pick any area of router performance or usage and there's a good chance there will be a known Superhub bug or omission there - the thing is an absolute lemon.
If the various bugs get on your nerves big time or you find it won't support something you need to do (eg override DNS, DynDNS support, QoS, use Wifi with decent performance in a different room, etc. etc.) then it can be switched to modem mode and you can then use a proper router.