My traffic grows each year and still earnings go down.
too early to report for a larger period because my site is relatively new, but the game is as follows: every time i get a little traffic boost, my epc (and/or ctr) goes down immediately. in fact it goes down so much, that the traffic increase often can't compensate. it seems as if google decides preemptively that the quality of visitor clicks must be worse in any case if the traffic goes up. very frustrating if you ask me..