Ability to report on number of simultaneous calls

Is there a way to be able to determine the number of simultaneous calls that are occuring on Asterisk (from the master.csv?)?

Basically, I want to understand my phone line utilization, so I can determine if I need to add more phone lines soon or not.

Thanks.

you can get a list of active channels via a call to the Manager API. Theres a script in the Nagios exchange that does this, I modified that script for my own reporting tool.