Affiliates - How much do you make each month in commissions?

I'm not really certain where the sales mostly come from, I assume my blog. I primarily only review for Eden; the other affiliate programs I actively (but not frequently) write about are Crystal Delights and Tantus.

For some reason, spring and early summer is a lot slower, my commissions were between 150-200 then. Other months of the year I've been between 400-500.