I believe Networx group and Andrew (Australian ?) is from Australia. Cricket should be a known sport to you, personally I admire Adam Gilchrist for the sportsman / person he is and am watching him in the IPL. Swing factor is the cricketing phenomenon of a ball getting extra turn..!
I am also using Watchwan (though not a big admirer) which monitors my router only. When I periodically check my usage at my ISP site, I get a difference (UL -.06% DL-1.24% TOTAL- 1.30% HIGHER) for the totals measured in a corresponding period in the Watchwan log. For others it could be LOWER too. But I doubt the monitors whatever at home and ISP would ever agree. When the quota is into GBs this could be crucial too.
Can you think of adding this feature for viewing purposes only? The statistics will be recorded as usual, but while viewing in the general screen / Quota control the display could be manipulated based on the user entered factors and the user wanting such an information.