California and Nevada are struggling with some of the nation's highest rates of workers who are looking for jobs or not putting in as many hours as they would like, new government data show.

The ranks of these individuals aren't reflected in the overall jobless rate in the U.S. Labor Department's monthly unemployment report. That report—July's figures will be released Friday—is the best gauge of the health of the labor market. But the overall jobless rate, which now stands at 8.2%, doesn't tell the whole story.

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