Even as the death penalty grows out of favor in the United States, the number of executions worldwide has risen to its highest level in 25 years, a new report on the death penalty from Amnesty International finds.

The human rights group recorded 1,634 executions in 2015, a number rivaled only by a three-year period beginning in 1988.

James Clark, Amnesty's senior death penalty campaigner, says the numbers can seem a bit misleading because the rise was driven mostly by three countries — Iran, Pakistan and Saudi Arabia, which accounted for 89 percent of all executions.

"The spike in executions, particularly in Pakistan and Saudi Arabia, leads to this global number that is so much larger than we've ever seen in recent years but that belies the fact that it's happening in such a small number of countries around the world," Clark said.

The global trend, Clark said, is clear: The death penalty is in decline worldwide.

The United States, which executed 28 people in 2015, was for the seventh year in a row the only American country to execute. But lately, the U.S. has significantly curtailed its use of capital punishment.

The U.S. arm of Amnesty International points out: "As of April 1, 2016, a total of 18 U.S. states have abolished or repealed the death penalty, and a total of 9 U.S. states have not conducted an execution in at least a decade — meaning that, for the first time since capital punishment was reinstated in the U.S., a majority of states have halted the death penalty in either policy or practice."

As we've reported, the death penalty has become historically unpopular among American voters and its use is also becoming increasingly rare.

"I think we're seeing the death penalty become isolated to a small number of outlier states, while really the rest of the United States is moving forward and following in the global trend that we just don't need the death penalty," Clark said.

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