Judging by the math you do not know the difference between a round trip and a contract traded.
If according to you each trader is "banging out" 5k r/t's a day and there are 10 traders then:
5000 x 2 =10,000(lots per day)
10,000 x 10(traders) = 100,000
100,000 x 20(trading days) =...