Methodology

To determine America’s least educated towns, 24/7 Wall St. reviewed five-year estimates of the percentage of adults 25 years and over with at least a bachelor’s degree in U.S. towns from the U.S. Census Bureau’s 2019 American Community Survey.

We used census “place” geographies — a category that includes 29,573 incorporated legal entities and census-designated statistical entities. We only considered the 29,320 places that had boundaries that fell within one of the 50 states or the District of Columbia.

We defined towns based on population thresholds — having at least 1,000 people and less than 25,000 people — and 13,332 of the places fell within these thresholds.

Towns were then excluded if bachelor’s degree or higher attainment rates were not available in the 2019 ACS, if the town’s 25 and older population was less than 1,000, or if the sampling error associated with a town’s data was deemed too high.

The sampling error was defined as too high if the coefficient of variation — a statistical assessment of how reliable an estimate is — for a town’s bachelor’s or higher attainment rate was above 15% and greater than two standard deviations above the mean CV for all towns’ bachelor’s or higher attainment rate. We similarly excluded towns that had a sampling error too high for their 25 and over population estimates, using the same definition.

The remaining 10,738 places were ranked based on the share of adults 25 years and over with at least a bachelor’s degree. To break ties, we used the percentage of adults 25 and over who have completed at least high school or its equivalent.

Additional information on the share of adults 25 years and over who have completed at least high school or its equivalent, median household income, unemployment rates for the 16 and older population in the civilian labor force, and population figures are also five-year estimates from the 2019 ACS.