Do you mean to say you want to see the bytes downloaded per second and the total bandwidth used so far in a convo / a given period of time (a week or a month) ??
There are other ways to find that out. I did try that once just for fun
What i did was i installed DU meter, did the necessary settings. And only opened a msn convo as an application that would use the bandwidth.
Then when i was having a convo, it showed me when the data was sent and how much was it .... It was quite small (obviously
)
Similarly i used the same method for checking out the bandwidth usage in audio and video conversations