Originally Posted by pompousjohn

In 1976 there were 219 million people in America. In 2014 there are over 319 million. That's a difference of at least 100 million people, over 30%.

So while that graph seems to show the rate of gun related incidents in schools being more or less stable over the last 38 years, it doesn't take into account the population growth.

So basically it seems you have less chance of being shot at school today than you did in 1976.