Orlando, Las Vegas, Sutherland Springs: three of the worst mass shootings in modern U.S. history all happened in the past 17 months.

As Denver journalist Kyle Clark grimly observed on Monday, the 1999 Columbine High School massacre that once shocked the world when two gunmen killed 12 students and 1 teacher, has been pushed off the list of the top 10 deadliest mass shootings in recent U.S. history.

The Columbine school shooting shocked America. As of today, it is no longer one of the 10 deadliest shootings in modern US history. — Kyle Clark (@KyleClark) November 6, 2017

Now, three shootings in the past 17 months are on the list, and, as CNN pointed out, two of the five deadliest mass shootings in modern U.S. history occurred in the last 35 days.

In June 2016, 29-year-old Omar Mateen killed 49 people and wounded 58 when he opened fire in Orlando’s Pulse Nightclub during Pride month. At the time, the attack was considered the worst mass shooting in modern U.S. history.

One year and four months later, 64-year-old Stephen Paddock opened fire on 22,000 people at a country music festival in Las Vegas, killing 58 and injuring hundreds more. The massacre remains as the deadliest mass shooting in modern U.S. history.

Following the Las Vegas shooting, the New York Times published an interactive feature showing that in the 477 days that had passed since the Pulse nightclub shooting, there had been 521 mass shootings, and no action from Congress on tougher gun laws.

On Sunday, just one month later, a lone gunman killed at least 26 churchgoers and injured 20 others at First Baptist Church in Sutherland Springs, Texas. It was the deadliest mass shooting in the state’s history. The victims range in age from 5 to 72.

According to Mass Shooting Tracker, there have been 377 mass shootings in 2017.