Your article made me drift back to my childhood. I would say that 100% of the bullying I experienced occurred during a two year period - during grades 7 and 8. I was in a school - rather small community - that housed grades 7 through 12 in one place. Made for an interesting dynamic. But I do remember that the years prior to this period and afterwards didn't contain any bullying that I can recall. I never said anything to anyone, not sure why. I sometimes think that the bullying victim acts in ways similar to a domestic abuse victim - blaming themselves or seeing themselves as partly the reason for it.
Interesting article. I agree. Creating the right culture is essential.