Young children (age 0 to 4) have a high rate of undercoverage in the decennial census and in surveys such as the American Community Survey (ACS). An interdivisional team is researching the causes for this undercoverage and assembling existing information about the living situations of young children. An important foundation for the team’s work is a baselining of the demographic, social, and economic characteristics of young children. The ACS is an ideal vehicle to measure the characteristics of young children along with the characteristics of the housing units and households where they live. Each year the ACS releases several tables about children. The tables included in this report expand on those tables to include greater age detail.

A comparison of 2010 Demographic Analysis (DA) estimates and 2010 Census counts for three partitions of children—those age 0 to 4, 5 to 9, and 10 to 17—found that only the two youngest age groups had an estimated net undercount in 2010 (U.S. Census Bureau 2012). We want to understand if living arrangements or other characteristics of young children differ in important ways from those of older children and if this might explain the difference in net coverage. U.S. Census Bureau (2017a) analyzed 2010 Census demographic, housing, and household data about children. The report summarized the characteristics and living arrangements of young children in three age groups (0 to 4, 5 to 9, and 10 to 17). It compared results for the youngest children (age 0 to 4) with those of the oldest children (age 10 to 17). Unlike censuses in the past, the 2010 Census asked a limited number of questions about each person and each household. This report expands the previous analysis by using the more detailed social, economic, and housing data that are now collected in the ACS.