The rapid rise in pay for corporate executive officers, which stands in contrast to the stagnant wages of many Americans, is a key driver of inequality that’s not clearly tied to talent or performance, a new report from a liberal think tank finds.

The Economic Policy Institute report says this means CEO pay could be reduced without hurting economic growth or productivity. EPI says top U.S. CEOs make 300 times more than typical American workers, down from a peak of 376 times in 2000 but well above levels seen in the preceding...