Chief executives of the nation’s publicly traded companies saw their collective pay decline by almost 20 percent in 2023, new analysis shows, and even experts are stumped as to why.

Trends in CEO compensation generally mirror those of the stock market, in part because pay packages for chief executives have largely been tethered to stock performance for five decades. But a recent report by the Economic Policy Institute found that realized compensation for CEOs - including base salary, bonuses, stock awards and stock options - fell 19.4 percent from 2022 to 2023, a strong period for the U.S. economy and for Wall Street.

Subscribe to The Post Most newsletter for the most important and interesting stories from The Washington Post.

“This is probably the first time I can remember where we saw stock market go up and [CEO] pay go down,” said Josh Bivens, chief economist at the Economic Policy Institute, a left-leaning think tank. It’s left researchers questioning “whether this is a blip or some promising evidence that CEO pay is getting a little more disciplined.”

CEO compensation has soared 1,085 percent since 1978, according to the EPI’s analysis, compared with a 24 percent rise for the typical worker, so the idea that corporate boards have suddenly gotten more disciplined about CEO pay is “a little hard to believe,” Bivens said.

The EPI’s annual CEO compensation report evaluates the 350 largest publicly owned U.S. companies that sell stock on the open market, drawing on data from S&P’s Compustat database.

Ballooning executive pay is a major factor shaping the chasm between top earners and everybody else. Private sector employees have experienced wage growth since the pandemic, with pay and benefits climbing more than 5 percent in 2022 and 4 percent in 2023, according to data from the Labor Department. But those gains have done nothing to close the gap between workers and chief executives, who earned 290 times as much as the average worker in 2023, according to the EPI. In 1965, it was 21 times as much.

CEO pay packages have drawn outrage from unions and worker advocates amid labor disputes involving Hollywood, the Big Three automakers and Boeing. Although strikes yielded historic wage gains for workers in the past year, the gap in pay between the rank and file and the C-suite is as big as ever.

“The escalation of CEO compensation - and of executive compensation more generally - has likely helped fuel the wider growth of top 1% and top 0.1% incomes, contributing to widespread inequality,” the EPI’s analysis states.

The “puzzling” dip in CEO pay amid a strong stock market could have something to do with a “shift in stock-related pay away from options,” the EPI researchers said, adding that they expect “this overall divergence will likely turn around with the stock market gains so far in 2024.” The S&P 500 is up nearly 22 percent this year.