Census Bureau Releases Experimental Estimates of State and County Undercounts and Overcounts of Young Children in the 2020 Census

APRIL 11, 2024 - The U.S. Census Bureau today released new experimental estimates showing children ages 0 to 4 were undercounted in the 2020 Census in every state. Additionally, there were undercounts of children ages 0 to 4 in more than 4 out of 5 counties included in this release. The experimental estimates are available only for counties with a population of 1,000 or more children ages 0 to 4, and are based on the Census Bureau's Demographic Analysis (DA) estimates.

The number of U.S. children ages 0 to 4 counted in the 2020 Census was previously found to be about 1 million lower than the benchmark population estimate - an undercount of 5.46%. This was a larger undercount than any other age group.

Today's release of net coverage error rates for young children comes from the Census Bureau's DA estimates. Instead of conducting a count based on responses collected or on behalf of each household like the 2020 Census, DA uses administrative records to estimate the size of the population and compares those estimates to census counts to assess the accuracy of the 2020 Census.

"The Census Bureau recognizes historical undercounts of young children in our decennial census as well as an under-representation in our demographic surveys. We know these undercounts are often correlated with undercounts of certain race and ethnicity groups along with other factors that we were not able to measure directly. We are diligently working to address this issue," Census Bureau Director Robert Santos said. "Our goal is to accurately count every child in the census and to ensure they are fully represented in our surveys. Quality statistics help communities better understand their needs and seek resources."

DA is one of two methods the Census Bureau is using to assess coverage of the 2020 Census. The other one is the Post-Enumeration Survey (PES). DA uses current and historical birth and death records from the National Center for Health Statistics, data on international migration, and Medicare records to independently produce estimates of the U.S. population on April 1, 2020. Traditionally, DA estimates have been produced at the national level for the total population. Today's release expands on the official approach by incorporating birth records from 2015 to 2020 and adjusting for migration between counties.

"These experimental estimates build upon previously released quality measurements to use new data and methods for young children in the 2020 Census," said Eric Jensen, senior advisor for Population Estimates and Coverage Measurement in the Census Bureau's Population Division. "They offer a unique glimpse into the geographic distribution of the coverage of young children in the 2020 Census and are critical in identifying areas where improvements are needed to more accurately count children in the 2030 Census."

The net coverage error for young children varied by geography, race and Hispanic origin, household structure, and other demographic, social and economic characteristics.