The statistics section will give you a short overview about what is going on with your relay. It will only show up, if you are running a relay.
Who is who?
Fingerprint
Every relay has got a fingerprint by which it is uniquely addressed within the Tor network. Click on it to see all the information about your relay the Tor network has gathered on http://atlas.torproject.org.
Relay Address
In case you have not entered anything into the "Relay Address" field of the relay configuration section, Tor will guess your external IP address which is shown here.
Total Traffic
The total traffic Tor has transferred since the last start of the service.
Accounting
If you are using traffic limits for Tor, you will see information about that here.
Interval
Shows when the current interval has been started and when it will end. All dates and times are shown in UTC.
Traffic
Shows the already used traffic and what is left.
Connected relay
Shows a list of all connected relays. Click on the name of the relay to get to it's Atlas page. You will also see the IP address of the relay and the port it uses. The country in which is the relay is running is shown by a little flag next to the IP address.
The last column in the list shows the estimated connection bandwidth to the relay.