North Dakota's low un-employment isn't because people are leaving the state because there are no jobs to be had. It is the opposite. There are/were lots of jobs. Not as good now as it was a year ago, but when you look at the link below. you might be surprised where some towns like Williston went from 10,000 workers in the 2000 census, to over 16,000 workers today. The number of jobs and workers has increased, not gone away. Williston-Tioga areas (Williams county) has a 2.2 unemployment rate...one of the lowest in ND.
Labor Force: Williston, ND Micropolitan Statistical Area, North Dakota; NSA
you can use this same site to browse to other cities and states.
Bismarck, Minot, Dickinson, Fargo, and Grand Forks also had encouraging increases.