Idaho’s Center of Population Continues Westward Shift

Once a decade, the U.S. Census Bureau releases estimates of the U.S. center of population, a common practice since 1790. The bureau defines the center of population as a balance point — the point at where an imaginary, flat, weightless and rigid map of that area would balance perfectly if each person was assigned the same specific weight.

The center of population is one of several measures that are useful for visualizing changes in population over time. The location and distance of the center of the population, relative to some point such as the geographic center or previous center of the population, indicate the aggregate magnitude and direction of the population growth.

Where is the center of the population of Idaho?

In 1920, Idaho’s total population was 431,866, with the center of population located in Custer County about 17 miles east of the nearest town of Stanley – or approximately 7.6 miles west of Idaho’s geographic center. Idaho’s center of population has continued to shift westward since the early 20th century, passing near Stanley in 1980, and ultimately crossing into Boise County by 2010. The largest shift in the center of population occurred between 1990 and 2000 when Idaho’s population astoundingly grew by about 30%. As of 2020, Idaho’s population was 1,839,106, with the center of population located in Boise County about 15 miles west of Stanley – or 64 miles northeast of the city of Boise.

Why is the center of the population shifting?

Idaho’s recent shifts in the center of the population shows that a higher share of the growth in population is occurring in the western part of the state. Idaho’s population grew by more than 1.1 million in the past 100 years, with approximately 50% of this growth occurring in the southwestern part of the state.

Bonang.Seoela@labor.idaho.gov, regional economist
Idaho Department of Labor
(208) 788-3526 ext. 3820