The number of murders in the United States jumped by nearly 30 percent in 2020 compared to the previous year in the largest single-year increase ever recorded in the country, according to official FBI statistics released Monday.

The data show 21,570 homicides in the U.S. in 2020, which is a staggering 4,901 more than in 2019. The tally makes clear — in concrete terms — just how violent last year was.

The overall violent crime rate, which includes murder, assault, robbery and rape, inched up around 5 percent, while property crimes continued their long-running decline and dropped 8 percent from 2019.

But the spike in murders jumps out in the FBI report because of the sheer scale of the change.

Jeff Asher, a data consultant who studies crime rates, said the increase is the largest since national records began being kept in 1960s.

The murder rate is still below its historic peaks reached in the 1990s, but the figures from 2020 show that the problem has become much more widespread.

"In the 90s, New York and Los Angeles accounted for 13.5 percent of all murders nationally. Last year, it was under 4 percent," he said. "So it's a lot more diffuse than it was in the 90s."

In the latest FBI data, murder was up more percentage-wise in cities with a population between 10,000 and 25,000 than in cities of 250,000 to 1 million.

"It was up over 30 percent in both, so neither was good, but it was worse slightly, percentage-wise in smaller cities," Asher said. "It was bad everywhere. There's not a good murder takeaway there."

Much of the violence was driven by firearms, with nearly 77 percent of murders being committed with some sort of gun.

That figure has been slowly inching up over the past several years, Asher said, but he said 2020 is the first time that figure has eclipsed 75 percent.

The FBI report does not delve into reasons behind the increase or decrease in various crimes. But researchers say a range of factors contribute to annual variations, and the turmoil of 2020 — including the coronavirus pandemic and the fallout from George Floyd's murder in Minneapolis by police — likely played a role.

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