How Brekeke PBX counts calls?

A peer to peer call between two pbx users is counted as 1 call
call transfer:
each transfered call is counted as 1 new call
for example,
A call B: this is counted as 1 call
B transfer call to C, and C is ringing: this is counted as 1 new call to C
after C answers the call and B hangs up: the number of calls is counted as 1 again
voicemail:
each access to the voicemail by 8/08*ext/07*ext is counted as 1 call
voicemail in forwarding destination(no answer, busy) is not counted as a new call
auto attendant:
each call to the auto attendant is counted as 1 call
when auto attendant is dialing the transfer destination, it is counted as 1 new call (while transfer destination is ringing)
after the destination answered the call, or no answer/busy, the call is counted as 1 again
ring group:
each call to a ring group number is counted as 1 call no matter how many phones are in the ring group
conference call:
the number of calls is the number of users in the conference room minus 1
call monitoring:
the call with the supervising phone is counted as 1 new call

System message