When is an incident involving a school-related shooting not an incident involving a school-related shooting? Don’t ask the Department of Education. As NPR reports, the federal government has no idea how many times a gun goes off in an American schools each year.

The U.S. Education Department released a study earlier this spring reporting that during the 2015-2016 school year, “240 schools … reported at least 1 incident involving a school-related shooting.” Then NPR decided to check their work.