I noticed this with my commission too. I wondered if it had to do with the value of purchases relative to bitcoin's value, since it is stated in the value of bitcoin. But it's too much of a fluctuation for that to be an explanation (like, a third of what it was before).
Footnote: How the heck did you get 200 people signed up? Impressive.
Mine is doing the same thing! http://prntscr.com/ia38s7