To find the most unique ancestry in each state, 24/7 Wall St. reviewed the ancestry question in the American Community Survey (ACS) 5-year averages for the year 2014 – 2018. The question is based on self-identification and answers represent ancestry groups with which people most closely identify. The 106 single-origin ancestries (excluding combinations of two or more races) represented in the data are based on a combination of the most common responses to the survey as well as classifications by the Census Bureau.
The most unusual ancestry in each state was determined by calculating the location quotient for each ancestry and taking the largest ratio relative to the U.S average. For example, if 20% of a state population is Scotch-Irish, and the Scotch-Irish comprise 10% of the U.S. population, then the location quotient would be 2.0. If that location quotient is the highest of any ancestry in the state, then that is the most unusual ancestry in the state. The racial composition, language spoken at home, total population and educational attainment were also from the ACS 2018 5-Year Estimates.