The county had been the least-populous county in the United States, with a 2010 census population of only 82 persons (an increase of 22.4% over the 2000 figure of 67 residents), but the 2015 estimate by the US Census Bureau places it as the second-least populous county in the US. With an average of only 0.0646 inhabitants/km2 (0.167/sq mi) as of 2015, the county is also the least-densely populated county outside of Alaska. (Lake and Peninsula Borough and North Slope Borough in Alaska are both lower, as is the Yukon-Koyukuk Census Area, which is not a county.)