Chart: What's the real unemployment rate?

The U.S. Labor Department said Friday that the unemployment rate was 5.5 percent in March—but does that rate tell the real story?

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A number of economists look past the "main" unemployment rate to a different figure the Bureau of Labor Statistics calls "U-6," which it defines as "total unemployed, plus all marginally attached workers plus total employed part time for economic reasons, as a percent of all civilian labor force plus all marginally attached workers."

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In other words, the unemployed, the underemployed and the discouraged—a rate that still remains high.

The U-6 rate fell in March to 10.9 percent, the first time it has been below 11 percent since Aug. 2008.

The trend in U-6 has been somewhat more volatile than in the main unemployment rate as well. The U-6 rate is down 170 basis points over the last year, versus a 110 basis point decline in the main rate (also known as U-3).

The U-6 rate has held firm in the double digits since June 2008. It most recently peaked at 17.1 percent in April 2010.

By CNBC