BOISE, Idaho — The Board of Directors of the Community Planning Association of Southwest Idaho (COMPASS) accepted the 2021 population estimates for Ada and Canyon Counties in its latest Board meeting.
The combined population for both counties is estimated at 761,680, an increase of just under 24,000 from 2020, according to COMPASS. Meridian had the largest increase in the Treasure Valley, growing by just over 8,500 in the past year.
COMPASS updates its population estimates on April 1 each year, using the most recent decennial Census count as the base. However, due to delays because of COVID-19, data from the last Census have not been released. COMPASS says the 2021 estimates are based on 2010 Census data.
“We are eagerly anticipating the release of the 2020 Census data later this year,” states COMPASS Principal Planner and demographer Carl Miller. “The decennial Census provides a once-in-a-decade opportunity to get full population counts and information about the characteristics of our communities.”
Building from the Census counts, COMPASS updates the population estimates using local building construction permits, current household sizes and vacancy rates, and recent expansions of city limits. That information not only allows COMPASS to estimate annual population growth, but also to reflect changes in how it is distributed among cities and counties.
"While the region as a whole has experienced rapid growth year over year, the estimates are calculated based on locations for new residential construction and changes in local vacancy rates,” explains Miller. “That way, we can tell what parts of the valley, and of each community, are growing fastest. Being able to track those changes on a local scale, as opposed to just broad regional growth, is important to address future needs.”
The 2021 population estimates can be found on the COMPASS website.