The number of murders across the United States declined sharply for much of 2024, continuing a recent downward trend, according to data collected by the Federal Bureau of Investigation, cities and independent researchers.

Murders spiked during the pandemic, and crime became a central focus of President-elect Donald J. Trump’s campaign message. Polls show Americans still see it as a major problem. And several high-profile homicides this year, including the recent killing of a homeless woman who was set on fire in a New York subway, may fan concerns.

But in 2023, the number of murders fell at the steepest rate ever recorded, according to the F.B.I.’s data.

That trend may be continuing, according to data from a mix of sources covering most or part of 2024. In some major cities, the numbers are at or below what they were before the pandemic.

Through October, data collected by the Real-Time Crime Index, based on reports from hundreds of law enforcement agencies, showed a nearly 16 percent decline in murders from 2023. The F.B.I.’s preliminary data for the first half of the year showed an even steeper decline.

But the F.B.I.’s data for the year is not yet complete, and it will not be until next year. Even with all of the statistics, the data set may not reflect the fullest picture on crime across the nation, as some law enforcement agencies do not report their numbers to the F.B.I.