On
this page you may see the difference between service calls and rejected calls.
The service call statistics have been introduced quite late. For this reason it will take some time to catch up and become realistic. Please take in account that about 75-85% of all registering attempts on connected networks are coming from spammers.
I don't know if local logging would be of a great advantage, since it would require to add quite some code in order to make the collected data comfortable to read and observe.