Monitoring total or per user transfer

Hello,

I've been trying to find a way to monitor how much data is downloaded by each of my users (or at least total transfer by the server). Is there any way to do this with FileZilla Server or must I switch to another? Which would you suggest if I must switch? I've been searching for this and had no luck. I wanted to be able to see if one user is using a disproportional level of bandwidth compared the the others. Thanks.