Counties where the population of young children are growing the most already had high net undercount rates for young children in 2010. The big increases in their young child populations suggest that unless the Census Bureau and the counties take action, these counties will suffer even higher net undercounts of young children in 2020.
In the 2010 Census young children (ages 0 to 4) had a higher net undercount and higher omissions rate than any other age group. As we look forward to the 2020 Census, it is useful to see which parts of the country are experiencing an increase in this vulnerable population.
Table 1 below lists the 25 counties with the largest increase in the number of young children between 2010 and 2017, the most recent data available. (Nationally, there has been a slight decrease in the number of young children between 2010 and 2017, so these counties’ growing population of young children is even more striking.) Six counties had an increase of more than 10,000 young children between 2010 and 2017.
Table 1 also shows the net undercount rate for young children in the 2010 Census for each of these 25 counties. The places young children are increasing the most are also places that had a high net undercount of young children in the 2010 Census. The average net undercount rate for these 25 counties was 6.1 percent which is about 50 percent higher than the national net undercount rate for this age group in the 2010 Census. Three of these counties (Washington DC., Hildago County, Texas, and Osceola County, Florida) had net undercount rates above 10 percent in 2010.
In addition, nine of these counties have seen their young child population grow by more than 10 percent, suggesting that the net undercount of young children in 2020 is likely to be even higher than their 2010 undercount might suggest. These counties include: Washington, DC; Fort Bend County, Texas; Franklin County, Ohio; Orange County, Florida; Hillsborough County, Florida; Montgomery County, Texas; San Francisco County, California; Hudson County, New Jersey; and Osceola County, Florida.
The fact that young children are increasing the most in areas of the country that already had high net undercounts of young children in 2010 suggests that both the Census Bureau and the communities that have seen a big increase in the number of young children since 2010 must focus on counting this population in these communities if we want to avoid an increase in the net undercount of young children in the 2020 Census. The population of young children, particularly those living in the counties shown in Table 1, need to be a high priority for the Census Bureau in the 2020 Census. Moreover, since other research shows that young children are missed for different reasons than adults, the Bureau and the counties must work differently to count young children than they do adults.
Dr. William O’Hare has more than 40 years of experience as an applied demographer and expert data analyst. For fifteen years prior to his retirement, he ran the KIDS COUNT project at the Annie E. Casey Foundation. He is the author of the book, The Undercount of Young Children in the U.S. Decennial Census, published in 2015. He holds a PhD from Michigan State University.