The focus on unemployment in America has started to wane a bit; the rate has fallen from 7.9% at the beginning of 2013 to the current 7.5%. One state that has been doing its part to help lower this average is North Dakota. Thanks to the booming Williston Basin, and the Bakken Shale in particular, unemployment there is only 3.3% as of the end of March. This ranks it as the No. 1 state in the country for employment.

Citizens of North Dakota have also been blessed with the seventh ranked GPD per capita in the United States. When examining why, look no further than the 400% growth witnessed in the state's oil and gas industry since 2005. Tune in below to learn about four companies that have been instrumental in these advancements.

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