unemployment problem is bigger than nyc and la combined...,

cnnmoney | Forget the unemployment rate. The employment rate -- the percentage of adult Americans who hold a job -- has barely budged in the past three years. It's hovering near its lowest level in three decades, and it's unlikely to improve when the Labor Department releases its May jobs report on Friday. 

About 58.6% of the civilian population over age 16 had a job as of April, according to the U.S. Bureau of Labor Statistics. This rate -- officially called the "employment-population ratio" -- has been stuck in that range for several years. The last time it was this low was in 1983.

Looking at the job market using that measure paints a stark picture. Sure, companies have been hiring, but they've been creating jobs at a pace that merely keeps up with recent population growth. It's not enough to also make up for the jobs lost in the crisis.

That's why the needle simply hasn't moved.

Related: Unemployment problem is bigger than NYC and LA combined

Contrast that with the tale told by the unemployment rate, which fell from 10% in October 2009 to 7.5% in April. The unemployment rate only includes jobless people who have searched for work in the last four weeks. It skips over those who left the labor force entirely because they retired, went back to school, or simply gave up on finding a job.

"The unemployment rate is really not that helpful right now in understanding trends in job opportunities because we've had so many dropouts," said Heidi Shierholz, an economist at the Economic Policy Institute, a liberal research group.

The employment-population ratio isn't perfect either.

Over time, it's expected to decline as the U.S. population ages. Eventually, a wave of Baby Boomer retirements will leave a smaller proportion of the U.S. population participating in the workforce.