Click
Super Poster
There is no set number and it also depends on the person and the content they are creating as some can make the ball role the whole time but others it comes in waves but it really depends on the viewer and many other factors. Really when you start getting into 4 - 5 digit numbers that is probably when you would start seeing a number rolling over since you have a large audience at that time.
I've gone from 1/month to 1/week to 1/day and have passed everything inbetween.