[otrs] An answer: statistics

Hello, We are using OTRS in a corporate environment. Our operators sending his answers to clients using OTRS. I want to have some statistics for each operator: how many tickets/articles they answered during the period, average time for the one answer, average articles number within the ticket and so on like this. Is there any ready to use statistics packages available from OTRS team or from any other developers/OTRS users? I believe, this is very actual question, but I found no any information on this. Thank you. -- Peter