Two users logged in, but only one shows session traffic

I am logged in as two users, only one of which is displaying traffic stats, despite frequent switches between users. Is there a traffic reading error, or is there a setting that I have missed? Note, the traffic displays on the first user to log-in on the computer, so not sure whether all traffic is logged against this user, or all traffic on the second user is completely missing. To me, it looks like the latter.

When more than one user is logged on at the same time, both users usage will be recorded correctly but only attributed to the user who logged in first.

The reason for this is that NetWorx can't tell what traffic belongs to which user as it can only know "X bytes of data was sent/received through adapter Y". There's no way to know which user generated that traffic.

So when two or more users are logged in, the second and following instances don't make any records to allow the first user to handle it. Otherwise any readings would double (triple, etc).