A quarter of Americans haven't gotten a raise in years, and it's part of a pattern that's baffling economists

While a majority of the respondents in the labor force have gotten a raise in the last year or so, about a quarter haven't increased their pay in over three years or ever.
Economists are baffled by the sluggish wage growth of the past few years, but say it could be explained in part by companies prioritizing shareholders over workers and customers.
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Unemployment in the United States is at a 50-year low , a traditional signal of a healthy economy. And yet, it's still been tough for some workers to score a raise .

Insider recently teamed up with Morning Consult to survey 2,096 Americans about their financial health, debt, and earnings for its new series, " The State of Our Money ."

About half of the survey respondents said they are currently in the labor force. Of that group, 32 were Gen Z, 399 were millennials, 337 were Gen X, and 217 were baby boomers.

In total, a majority of those with a job (60%) have gotten a raise in the last several months to a year. About 11% last received a pay increase two to three years ago.

Still, 14% haven't gotten a bump in their pay in over three years and about 10% have never had a raise, together representing about a quarter of the respondents.

Looking at millennials specifically the largest generation in the US workforce right now 19% either haven't had a raise in more than three years or never had one. Nearly 9% of Gen Xers and 8% of baby boomers say they've never gotten a raise.

Workers have lost some of their bargaining power, economists say

In September, the labor force participation rate among 25 to 54-year-olds reached nearly 83% , the highest it has been in the decade since the Great Recession. Such low unemployment should mean that employers are bumping up pay to keep current employees and lure new ones, but that's not the case, Business Insider's Rachel Premack reported .

Even economists are baffled by the sluggish wage growth, Premack wrote, but they have a few theories. In short, companies appear to be prioritizing shareholder interest over their employees.

"There is this idea that shareholders are the one set of stakeholders that deserve the largest share of a company's profits, rather than balancing the need of other stakeholders like workers or consumers," Jake Rosenfeld of the University of Washington in St. Louis told Premack.

In addition, the reduced presence of unions and a general decline in labor standards have dampened employees' bargaining power.

According to the Insider and Morning Consult survey, Gen Xers, defined as ages 39 to 54, were nearly twice as likely as millennials to say they hadn't received a raise in over three years. Census data shows that earnings tend to plateau for the typical American between their mid-to-late 30s to early 60s, with workers in that age range all having median incomes of about $50,000 to $55,000.

Check back on " The State of Our Money " throughout the month for more findings and analysis.