Many states are experiencing rapid labor-force gains as the economic expansion hums along. In Wyoming and West Virginia, the situation couldn’t be more different.

Since the recession ended in June 2009, Wyoming’s labor force has contracted by 5.1%, the biggest drop of any state in the nation during this period. West Virginia is next, with a decline of 4.5%, according to Labor Department data. Other states have shed workers, too, including Vermont, Kansas and Ohio.

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