This documentation provides information on overlapping race and ancestry estimates in the American Community Survey (ACS) beginning in 2024. The ACS has collected and disseminated data on race, ethnicity, and ancestry since 2005. Beginning in 2020, the Census Bureau implemented changes to the race question in both the 2020 Census and in the ACS based on extensive research and community outreach. Dedicated write-in response areas and examples were added for the “White” racial category and the “Black or African American” racial category. Additionally, improvements were made to the way write-in responses to the race question were processed and coded. The improvements made to the 2020 race question design, processing, and coding enabled a more thorough and accurate depiction of how people self-identify. These changes made it possible to tabulate data on the many detailed race groups reported in the ACS. Please see the ACS User Note, Improvements to the Race Question for more details.

Updates to ACS race data products reflecting the improvements made to the race question were instituted across three data years. In 2022, additional detailed Asian, Native Hawaiian and Other Pacific Islander, and multiracial groups were added to existing tables. In 2023, new tables were added for detailed American Indian and Alaska Native tribes and villages to replace tables providing data on tribal groupings. In 2024, new tables were added for detailed White and Black or African American groups.  

Historically, the ancestry question, which is an open-ended question that asks for a respondent’s “ancestry and ethnic origin,” was the only source of published data on detailed groups for the White, Black or African American, and Some Other Race populations. Prior to 2020, ACS data on detailed White, Black or African American, and Some Other Race populations, such as Irish, Lebanese, Haitian and Brazilian, were primarily collected and tabulated through the ancestry question. Starting with the 2024 ACS data products, these groups will be available in race and ancestry tabulations, leading to instances of “overlapping” groups or estimates. The overlapping group estimates may differ due to differences in the way race and ancestry data are defined, collected, processed, and reported.