KNOXVILLE, Tenn. (WATE) — Researchers at the University of Tennessee released a study Wednesday estimating that Tennessee’s population could grow by one million over the next two decades.

The report released by The Boyd Center for Business and Economic Research offers new population projections through 2070 for all 95 counties with breakdowns by age and race.

With the state’s population listed as 6.9 million following the 2020 Census, researchers project population growth could push Tennessee’s population to nearly 8 million by 2040.

The main driver of state population growth will likely occur in the 13-county Nashville Metropolitan Statistical Area. Researchers estimate this area will grow by 563,000 people in the next 20 years, accounting for 57 percent of the state’s projected total increase.

The Knoxville Metropolitan Statistical Area, which is comprised of Knox, Blount, Anderson, Loudon and Union counties, is projected to grow by 13.3% over the same time frame. Current projections would add over 116,000 new residents, pushing the Knoxville MSA population to nearly one million.

Knox County is estimated to add over 80,000 residents by 2040, an increase of 17.2%.

The state’s 78 rural counties are expected to add more than 225,000 new residents, an increase of 8.9 percent. Urban counties are projected to add about 765,000 residents, an increase of 17.5 percent.

Projections estimate Tennessee’s median age will climb from 38.8 years to 40.7 years by 2040, driven by an increase in the senior population. Matt Harris, associate professor of economics and researcher for the Boyd Center population projections, notes that the senior population growth is expected to account for roughly half (47.2 percent) of the state’s total projected increase over the next 20 years.

“Most of the growth in the senior population is driven by continued aging of the cohort born in the late 1950s and 1960s rather than by older individuals moving to Tennessee, although retirees moving to Tennessee do play a part,” Harris said.

The number Tennesseans aged 25-54 is projected to increase by 7.9%, a slower rate than the state’s population as a whole. Tennessee’s population is estimated to grow by nearly 15% by 2040.

Harris states that this lag in growth of the working-age population coupled with the growing senior population could constrain the workforce as more families take on elderly care responsibilities.

“As the number of seniors in Tennessee continues to increase, so will the number of individuals requiring care. Much of that care is provided by families, particularly in areas where there are not options for formal care—either in-home or residential,” Harris said. “There is a considerable body of research showing that informal care to older relatives decreases engagement with the labor force.”

Projections could change as age, sex and ethnicity breakdowns from the 2020 Census have not yet been released. The center is considering the release of an additional projection update in the fourth quarter of 2022 if sufficient new data is available.

“Ultimately, these projections serve as a very interim update,” said Harris. “Many of the factors that we evaluate for this project, including births, deaths, and state-to-state migration, have changed in some way due to the pandemic. In some cases we know the degree of change and in other cases we are still waiting on data that will tell us the degree to which population will be affected in the long term.”