avg throughput

hi 
this really an urgent request 
I am using multi cast protocols " pimds, dvmrp and bts in ns2 
where I have 2 src node and 4 receive nodes 
and so I have 2 groups each related to a source 
I need to find the avg throughput of the system 
by finding the throughput per second for each receiver first 
I suffering in implementing the concept using awk file 
please I need an urgent help 



Eng. Abeer"اللهم علمنا ما ينفعنا و انفعنا بما علمتنا وَ زِدْنا علماً "