it's the result of community commpetition to get on top 200 hourly list
by the look of it, threshold should drop even lower soon
anyway, I was off from solving captcha in the last 2-3 days
I started for about half hour (top) and my result was reaaaaally bad
then I continue for another half hour (bottom) and ...whew... I managed to do better
I think that first half-hour is my worst record
if you were wondering, those stats are my js inject to monitor my claims