Or what about this... let's assume, overall, that we spend 3 minutes of time for every kill in Planetside.
Yes, that only amounts to 20 kills in an hour, but factor in all the time spent logging on, all those bad days, long boring hacks, and of course, all our days as noobs, when we were getting <10 kills an hour...
In my case, 70,000 X 3 = 210,000 minutes = 3500 hours