You would need to enable Call Detail Records (Call Manager service parameter) and you would also need to enble logging of calls with zero duration (Call Manager service parameter) so that you could catch the missed calls. Once you enable this, you can either send the CDRs to an off box server or you can enable CDR Analysis and Reporting (CAR) locally on the publisher. CAR is mediocre but it may get you want you need. it will also (at a minimum) give you a way to dump the raw data so you can parse it yourself (e.g. in a spreadsheet). See this link:
http://www.cisco.com/en/US/partner/docs/voice_ip_comm/cucm/service/6_0_1/car/cmcarbk.html
HTH.
Regards,
Bill
Please remember to rate helpful posts.