A reminder that you really need to get as many raises as you can before you turn 40

Screen Shot 2016 09 28 at 10.57.10 AM

(Liberty Street Economics)

Real wage growth — or the lack thereof — has become a hot-button issue in the US.

It is something you often hear about in the race for the White House. In simple terms, many Americans feel like they're not doing any better than they were five or 10 years ago. And sure enough, growth in wages minus inflation has fallen sharply over the past 30 years.

"Our analysis shows that this economy-wide average real wage growth rate has declined by a third since the mid-1980s," researchers at Liberty Street Economics at the Federal Reserve Bank of New York wrote in a post Wednesday.

The reason, according to the Fed, has to do with demographics. Real wage growth tends to be concentrated in the early years of a career, when new professionals are learning on the job and rising through the ranks.

"Real wages tend to rise early in a worker's career, flatten out mid-career and then decline as the worker approaches retirement," the researchers wrote in an earlier post. "This inverted U-shape pattern is a well-established feature in the labor economics literature."

Screen Shot 2016 09 28 at 10.52.50 AM

(Liberty Street Economics)

As America's baby boomers age, more and more people are moving in to a mid-career slowdown and preretirement decline. They're not doing the things that tend to lead to big pay increases, like investing in new skills and moving around from job to job.

And that is dragging down the total real wage growth figure.

"The fraction of the US population in the fast real wage growth phase has declined from close to 60 percent in the 1980s to the mid-40 percent range recently," the researchers wrote. "Correspondingly, a greater fraction of the US population is now in the flat and declining life-cycle phases of real wage growth."

This has significant implications for the economy, but it also serves as a useful reminder that the early years of your career count for a great deal. In fact, real wage growth typically tops out at 40 years old. Brutal.

"Real wages, holding constant any cyclical effects, show positive growth that is concentrated early in a worker's career," the researchers wrote. "By age 40, real wage growth has typically declined to around zero."

NOW WATCH: The 'Mrs. Doubtfire' house is on sale for $4.45 million — here’s what it looks like 23 years later

More From Business Insider

• The CDC just added another country to the list of places with Zika — here's a map of all the places it has spread so far
  

• Federal Reserve Chair Janet Yellen forgot a key measure of the job market during testimony to Congress
  

• Evidence finds inflexible work hours play a huge role in the gender wage gap