If you're going to think about it in terms of social 'cost', you may as well think of it over the span of a person's life. Society has invested a lot of... capitol? ... whatever it is that society invests in these people. University students in particular have been a social burden for most of their lives. But the reason society bears this is that the investment will pay in increased social benefit once they graduate.
So students, at least, shouldn't kill themselves. And society should protect its investment by keeping them from doing it. A cold hearted analysis, but that's the name of the 'social cost' game.
Jeffrey Dahmer attended Ohio State University. Joseph Stalin attended seminary (!). Osama Bin Laden went to King Abdulaziz University.
Man, I'm almost up to literally advocating the devil now.
To be fair, flipping through the famously despised people, a really large % of them either dropped out of high school (Hitler, Manson) or college (Dahmer). I was going to say it was surprising, but really, when your sample set is people we all consider to be really messed up, it kinda makes sense.
So students, at least, shouldn't kill themselves. And society should protect its investment by keeping them from doing it. A cold hearted analysis, but that's the name of the 'social cost' game.