How the Number of Young Children in Illinois is Changing

The general population in Illinois has been on the decline for the past few years, but have the numbers of young children in our state followed this trend? If so, are there any county-level differences when looking at population numbers over time for this specific age group?

According to estimates from the U.S. Census Bureau, all but nine of Illinois’ 102 counties have lost population since the last census count in 2010.

On the map below, you can hover over individual counties in order to view the percentage and numerical change in population over the past 9 years.

Note the gains in the heavily populated counties around Chicago, along with the south-of-Interstate 80 counties of Champaign, McLean, Monroe (outside of St. Louis), and Williamson.

So what about the population of young children (under age 5) in Illinois? Has this number also been on the decline? Census Bureau statistics indicate that indeed this is the case.

In the map below only eleven counties (out of 102) are showing gains above 1% in this age category. This is not surprising: according to the Brookings Institute, the child population is declining nationally and in 29 states – including in Illinois.

One interesting difference when looking at these maps side-by-side (see below) is that while the counties surrounding Cook (as well as Champaign and McLean Counties in Central Illinois) are gaining population in general, these same counties are losing numbers (or just holding steady) when you look at percentage change of young children. Another difference can be seen in the Southeast Illinois. Some of these counties, while losing numbers in the general population, are gaining in numbers of young children.

Birth rates can also help paint a picture of how the population of young children in Illinois is changing. According to the Center for Disease Control, in 2018 the national birth rate reached its lowest point in 32 years at 59 births per 1,000 women ages 15-44.

Using U.S. Census data 5-year estimates, which includes births to women ages 15 to 50, the U.S. birth rate shows a similar decline, from 56 births per 1,000 women in 2010 to 52 per 1,000 in 2016-18. In Illinois, the birth rate falls slightly lower than that, falling from 56 births per 1,000 women in 2010, to 51 per 1,000 in 2016-18. It is also interesting to note that this figure has held steady for the last three years

Line graph showing a fall in Illinois and US birth rates from 2010 to 2018.
Birth rates have fallen in the U.S. and Illinois since 2010

The map below shows the numerical change in birth rates for all 103 Illinois counties between 2010 and 2018. Note the trend of decreasing birth rates (in orange) in the northeast of the state (Cook and surrounding counties).

Finally, public kindergarten enrollment rates can also give a rough estimate of population trends. According to data from the Illinois State Board of Education, only thirteen counties in Illinois have experienced growth in the number of children enrolling in kindergarten. Moreover, these growth numbers are very modest (from 1 to 27 additional students).

Of course, countywide data can only give a general picture of how the population is changing in Illinois. Looking at data from smaller geographic regions such as municipalities, zip codes, and school districts can provide further insights.

Do you need to explore how these trends are affecting your school district or service area? IECAM is always happy to fulfill data requests specific to your region.

Additional Resources:

Population Projections by Age and Sex: July 2010 to July 2025 Illinois Department of Public Health