I really don't have time to be correcting everyone's arithmetic, but I feel the need to nip this in the bud and point out how bad math and bad comparisons can lead people astray. I provided 2 data points, which you quoted, demonstrating the effect of the change in commission. Then you added a 3rd data point showing the total commission instead of the change, which is misleading, and then said "it" more than doubled, which is ambiguous. If "it" is referring to the commission, then this is not just misleading, but incorrect. A $2500 item before the change is now $2539.80.