Sometimes Oil makes the last people you would expect, rich.

In Mountrail County, considered the "hub" of oil and gas production in North Dakota, the average income has roughly doubled in the last 5 years to over $52,000 per person.
This now causes it to rank in the top 100 richest counties in the US.

Bruce Gjovig, founder for the "Center for Innovation" at the University of North Dakota has been quoted as saying "the boom could be creating up to 2,000 millionaires a year in North Dakota".

Some of the residents who have oil and gas wells on their land are receiving more than $100,000 a month, although it is much more common for the royalties to be in the $50-60,000 per month range according to David Unkenholz who is a senior trust officer at First International Bank & Trust in Watford City. Watford city is also the seat of McKenzie County, which is considered to be the #2 oil producing county in North Dakota only surpassed by Mountrail.

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There is so much oil in Stanley that a well that was recently drilled underneath the city itself could result in many of the homeowners could end up with royalty checks.
No wonder the population has doubled to 3,200 in the last five years.

Unkenholz also said that a large amount of the money that comes in to the area is often stashed in checking and savings accounts which now have "ridiculously large" balances.

The amazing part of all of this is the lack of large homes, sportscars and shiny rings on wives fingers that you would likely expect from somewhere so rich from oil. It is more likely that the oil rush has surged the sales in pickup trucks, not sportscars.