(NPN) -- North Dakota was the only state in the United States to see an increase in self-employment from 2009 to 2013.

Washington, D.C. was the only other location to also see such growth, according to a recent report by CareerBuilder.com.

North Dakota saw 5 percent growth during that time and Washington, D.C. experienced 1 percent self-employment growth. All other states saw a decline in self-employment but certain metropolitan areas saw isolated self-employment growth, according to the report.

CareerBuilder attributed North Dakota’s numbers to an increase of real estate agents (up 69 percent), retail staff supervisors (up 36 percent) and construction laborers (31 percent). The jobs site said the increases were “likely byproducts of the oil boom.”

The study reported the following percentages of self-employment in the work forces of Northern Plains states in 2013: Montana, 9 to 9.9 percent; South Dakota, 8 to 8.9 percent; Iowa and North Dakota, 7 to 7.9 percent; and Wyoming, Minnesota and Nebraska, 6 to 6.9 percent.

Vermont had the highest self-employment rate at 10 to 10.9 percent and Delaware and West Virginia at 4 to 4.9 percent.

CareerBuilder says that prior to 2009 and the Great Recession, self-employment was on the rise but has fallen since then.