network activity

i tried for a while different shells but had no luck to get: the amount of downloaded/uploaded data in a session (in Mb). I changed my surf plan and my internet provider offers no method to monitor the amount of transferred data.
Some suggestions ?

I think the command line util netstat is a great utility, use the statistics option (-s) to see all statitics foreach protocol

do shell script "netstat -s"

Thanks DJ Bazzie Wazzie,
Uff.i tried too much at the point to oversee the important part.

i did some tests and compared the results with SurplusMeter.
However, results arent the expected numbers - dont know what i did wrong.

138 data packets (33053 bytes) retransmitted
251409 packets (452048797 bytes) received in-sequence

do shell script "netstat -s"
set f to 33053 / 1024 / 1024
set g to 452048797 / 1024 / 1024

f== 0.03152179718 instead of 15 MB
g== 431.107327461243, is correct

and both values relate to the total of data downloaded, not to my daily session of 1-2 hours i navigate.