When the final fatality count comes in, today’s shooting at Oregon’s Umpqua Community College may be one of the deadliest mass shootings in U.S. history. The New York Times reports that the 26-year-old gunman killed 9 people.

It is also part of a disturbing trend, one that many feel might just be an illusion of the 24-hour news cycle. Last year Jesse Singal wrote in New York that “Media coverage plays a big role” in the perception of increased shootings. “It's a visceral example of the availability heuristic— the easier it is for us to think of a certain type of event (whether a school shooting or a plane crash), the higher we rate its probability.”

Do we feel like there have been more mass shootings because we see more of them? It was easy to think so earlier this summer when Vester Flanagan shot Alison Parker and Adam Ward on camera, and much the same today as conflicting details of the Umpqua shooting rolled out of Twitter and flickered on CNN. Even Donald Trump told reporter Philip Bump this afternoon, “It’s happening more and more. I just don’t remember—years back, I just don’t remember these things happening. Certainly not with this kind of frequency.”

Trump’s memory isn’t failing him. Although there have been historical clusters of mass shootings in the 1920s, ‘30s, and ‘60s, mass public shootings (defined as having four victims or more) have been increasing, especially in the last few years. They've also become deadlier.

In 2014, the F.B.I. released a report of active shooter incidents ("an individual actively engaged in killing or attempting to kill people in a confined and populated area") that showed the number increasing both in frequency and in number of fatalities. Between 2000 and 2006 there were an average of 6.4 shootings annually, but between 2007 and 2013 the average more than doubled to 16.4. Researchers from Harvard using data from Mother Jones determined found a marked increase in mass shooting frequency since 2011: Between 1982 and 2011, a public mass shooting occurred on average every 200 days. Since 2011, that has increased to once every 64 days.