Census shows Illinois under-20 population declining faster than national average

By Sean Reed | The Center Square
The Center Square

(The Center Square) – Recently released data from the U.S. Census Bureau revealed Illinois has seen outsized shifts in its population by age demographic when compared to the national average.

The population of young residents in the state is decreasing at a rate multiple times the national average.

According to Bryce Hill, senior director of fiscal and economic analysis for the Illinois Policy Institute, the new data reveals demographics of the state’s population are shifting differently to other states.

“The 20s, 30s and 40s age groups nationally are growing between 4.3% and 5.5% over the past five years. Meanwhile, those groups in Illinois are growing at 1.2% – or slower than that,” Hill said.

He also said the youth, or under 20, population became smaller nationally as a result of decreased birth rates and the process of aging, but the population of young Illinoisans was falling at a sharper rate.

“The starkest contrast that we found was that Illinois’ young population, those who are under 20, is declining rapidly. That population has declined by about 7% since July 1st, 2020,” Hill said. “Meanwhile, the US as a whole, that population has only declined by about 2%.”

Hill said the state’s decline can’t be attributed to natural processes alone, but instead it’s a combination of factors that includes outmigration of residents from the state.

“We have very similar birth rates, we have a similar median age, we have a similar age distribution as the rest of the nation. However, the population trends are working against Illinois,” Hill said.

He noted lawmakers should be aware and seek to emulate the conditions in other states that Illinois residents are leaving for.

Previous outmigration data The Center Square reported on revealed one of the primary reasons people are leaving the state is due to the high burden of taxes placed on residents, especially compared to neighboring states.

The Tax Foundation reports Illinois ranks as 10th largest in terms of individual local and state tax collection per capita, according to data from the 2023 fiscal year.

All five states that border Illinois fell within the bottom half of the ranking based on the same data.

Hill said taxes are a likely culprit, especially as multiple major population centers in the state sit relatively near state lines.

He noted lawmakers will have to address long-term issues sooner if age demographics in the state don’t begin to course correct.

“[The data is] representing fewer and fewer taxpayers to shoulder the burden of government. We have very large fixed costs for government in the state of Illinois. Most notably, the state’s unfunded pension liabilities, which are right now hovering around $140 billion,” Hill said.

Other potential issues include a decline in the rate of people entering the workforce, making it potentially more difficult for employers to fill jobs in Illinois and potentially driving off new economic investment, according to Hill.