Bullying is a big problem worth addressing and it's not something that happens exclusively in public schools. It happens in informal adolescent peer circles, on social media, in private schools and basically anywhere where there are children gathered together.

Despite this fact, the cost is much higher than I expected it to be and even if the methods used have some built-in bias, I expect an objective figure to remain astronomical. Unfortunately, this is not an easy issue to tackle and it's probably impossible for it to get uprooted altogether. But it can surely be diminished.