A demonstrator holds a sign that reads "Everyone Counts" outside the U.S. Supreme Court in Washington, June 27, 2019. Andrew Harrer | Bloomberg | Getty Images

Despite years of warnings, census experts worry it's likely that children younger than 5 will be undercounted again in next year's survey – and that could mean more difficulty for low-income families reliant on government-backed services. One of the biggest stumbling blocks is awareness. Many households do not include young children when they return their census forms, according to people who study the population and demographics. Young children are difficult to count for many reasons, said Bill O'Hare, a census expert for the Count All Kids Committee. They tend to have young parents who aren't likely to fill out census materials and who might be in the middle of significant life shifts like career transitions and go through housing insecurity, which may make the census a low priority. "A lot of young kids are living with young single parents, and those are often very economically vulnerable parents. So they end up moving into other people's households more than older children would, so they would most likely be missed," O'Hare said. "That can be a problem with kids living with grandparents. The grandparent may not see the grandchild as part of his/her family, so many of those situations are viewed as temporary even though they may not be."

More risks for poor kids

O'Hare and others worry there hasn't been enough of a spotlight on this issue, which could result in less funding and resources for kids in low-income communities. Federal agencies use data derived from the census to create a budget every year. Over $900 billion in federal funds gets distributed annually to state and local governments, hundreds of federal programs, and individual households and organizations. About $160 billion goes toward initiatives specifically for young children, which gets divvied up into individual government programs. The Supplemental Nutrition Program for Women, Infants and Children, for example, received more than $6 billion in 2015, and foster care programs received $4.6 billion. Special education grants received about $11 billion. Several government programs geared toward children — like Head Start, the National School Lunch Program and the Children's Health Insurance Program — are also impacted by census results. Businesses also rely on census data to determine which locations would give them the best return on their goods and services. If there's not enough child representation in an area of interest, child-focused businesses like day cares or children's hospitals may choose to shut down or move.

A history of undercounting

Census administrators began paying closer attention to the issue in 2015, when the bureau formed a research team to determine the characteristics of the uncounted children. But undercounting has been a concern since 1790, when the first census came out, according to a spokesperson for the U.S. Census Bureau. Unlike other hard-to-count demographics, the percentage of uncounted children has been increasing since 1980, O'Hare said. Analyses of 2010 results by the bureau's research team show that 25% of uncounted children up to age 4 live below the poverty line. About 31% of that group live in a household that receives public assistance like food stamps or SNAP. Three in 4 live in a household with at least three people. These living conditions, the analyses point out, may make filling out the census low on the list of priorities for many families. One in 10 kids up to age 4 — more than 2 million children — were not counted in the 2010 census. Out of all demographics, this is the age group that gets overlooked the most, according to nonprofit organization Population Reference Bureau.

Possible fixes