Sure, but if it didn't result in seeking medical care, then maybe nobody ever hears about it. This being true both now, and when we were in high school, it is hard to judge if that number is too high to be plausible or not.
The 2.5% number is more directly comparable to past numbers, if we assume that suicide attempts that lead to requiring medical care are more likely to get reported somehow.
Maybe, in the past, some high schooler one night decides to drive his car faster and faster on a deserted road, hoping that it will end up with death by car wreck. Then, they decide against it, slow down, pull over, cry, and eventually go home. We never hear about it unless they admit to somebody that it happened. But, if they end up putting the car in a ditch and get treated at a hospital, perhaps we do.
My goodness what a depressing topic to comment on. Anyway, hope everybody out there reading this feels ok! If not, it gets better, keep trying!