We use Lync reporting to review activity. We are able to review a person's activity if the outbound call is successful (answered, voice mail, etc.) however, if an outbound call is made and the call goes unanswered - just keeps ringing until I hang up - there seems to be no data recorded regarding that call.

Is there a way to change this?

TIA

No, that appears to be by design.  I've had the same issue trying to build reporting for a response group for a hacked-together call center.  I can report on calls that flow to other queues or hit voicemail, but I can't report on calls that were never answered because they're simply not recorded.