For the first time in more than a decade, Bakken's oil production is showing a year-over-year decline.

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Thanks to the shale oil boom, the Bakken region has experienced years of unprecedented growth with each year dwarfing the year before. But things have changed since oil prices crashed one year ago.

The U.S. Energy Information Administration (EIA) released their latest drilling productivity report showing production across all the shale basins are in decline. The report estimates that in October 2015, the Bakken Shale produced 1.16 MMbpd (million barrels per day) of crude oil—1.8% less than the production levels in September 2015 and 4.6% lower than production was one year previously. This is the first time in over a decade that the production trends have gone backward. have reversed.

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Total oil output from major U.S. shale regions is expected to fall by 118,000 barrels a day to about 4.95 million barrels a day in December. State data shows that North Dakota produced 1.11 million barrels a day in September, down 1.1 percent from the same month a year ago.

To stay afloat, oil and gas producers release have had to scale back drilling operations and delay completing new wells. The full impact is being seen as companies release third quarter financial results this month that show huge losses, layoffs and budget cuts for many.

For more information go to eia.gov