ON JUNE 12th a gunman entered a gay nightclub in Orlando, Florida, and killed 49 people (including the shooter, the total count is 50). A further 53 were hospitalised. This was the deadliest mass shooting in American history. The shooter, Omar Mateen, was a 29-year-old from Florida. He had been interviewed by the FBI in 2013 after making statements praising radical Islamic propaganda, and again in 2014 by agents probing his ties to an American who travelled to the Middle East to become a suicide bomber. But the authorities did not find any conclusive evidence against him. As a result, he was able to buy at least two guns, including an AR-15 assault rifle. During the attack, Mr Mateen called 911 emergency services, pledging his allegiance to Islamic State.

Data on mass shootings are hard to come by. There is no broadly agreed-upon definition of what constitutes such an attack, and official homicide statistics do not separate them out from other murders. The statistics used in the chart above come from Mother Jones, a magazine, which compiles information on mass shootings from news clips.