But then again your argument seems to be that if something fails in the decimal % then it is a complete failure :Contrary to public perception, school homicides declined after 1993, although from 1997 to 1999 there was a series of copycat shootings stimulated by unprecedented media coverage.
However, a review of the National School Safety Centerís report (School Associated Violent Deaths :: National School Safety Center) identified 93 incidents when a student came onto school property and killed one or more persons over the worst ten-year period, 1992-3 to 2001-02. This means an average of about 9.3 cases per year or about once a month during the school year. Although we should strive to prevent all such cases, in a nation of 119,000 schools, a rate of 9.3 cases per year means that the average school can expect such an event about once every 12,800 years (119,000 divided by 9.3). This calculation is not intended to be a precise measure of risk, but an indication that there is a huge gap between the general perception of risk and the actual rate for the average school.