I run 2 charts (tick/minute), 2 quote sheets and 2 marketdepth/matrix boxes for each.... using ES, ER2, NQ and Ym..... runs less than 56Kbytes most of the day... except right at open and news/fomc... toucan
Consider using this tool to measure it. http://www.softpedia.com/get/Network-Tools/Bandwidth-Tools/FreeMeter-Bandwidth-Monitor.shtml