How to gather traffic flow data for each seperate IP address

RouterOS General
1

I work for an ISP and I have setup a router 450 which has a subnet 218.185.224.112/28 assigned to it.
Each IP address, in this subnet, is then assigned to an individual customer.
What I would like to do is gather traffic data for each separate IP address (customer) in this subnet which will then be used for billing purposes.
Currently we gather packet and byte data from wireless router boards, which has just the one IP address, for billing purposes; using snmp.

Can I configure the above router to log the packet and byte data for each separate IP passing through the router?
If so then how would I do this?
Will I be able to then extract that data using an snmp request?

2

Perhaps you can look for Traffic Flow,
http://www.mikrotik.com/testdocs/ros/3.0/aaa/traffic-flow.php
As it allows to monitor all the packets going through the router and Traffic Flow collector (different programs available) represents data in the graphic interface.