United States Census Bureau | An official website of the United States Government
Data Processing Error for
Migration Originating in
Connecticut in 2022 ACS
June 20, 2024
After the release of the 2022 American Community Survey (ACS) data products, an error was identified in the
Migration/Residence One Year Ago data among respondents who reported moving within the state of Connecticut or
from the state of Connecticut to another state or Puerto Rico. Due to the change of county boundaries in Connecticut,
[/programs-surveys/acs/technical-documentation/user-notes/2023-01.html] respondents reporting a Connecticut
county as their residence one year ago were systematically excluded from the donor pool for allocating missing or
inconsistent data [https://www2.census.gov/programs-
surveys/acs/methodology/design_and_methodology/2022/acs_design_methodology_ch10_2022.pdf] . This
processing error resulted in a decreased share of allocated migration geographies originating in Connecticut. The
error was present in 2022 1-year and 2018-2022 5-year data products [/content/dam/Census/programs-
surveys/acs/tech-doc/errata/Errata143_2022_CT_ImpactedDataProductList.xlsx] and Public Use Microdata Sample
(PUMS) [/content/dam/Census/programs-surveys/acs/tech-
doc/errata/Errata143_2022_CT_ImpactedDataProductList.xlsx] files.
The error had the impact of overestimating movers from different states and Puerto Rico to Connecticut,
underestimating movers within Connecticut, and underestimating movers from Connecticut to other states and Puerto
Rico. For Connecticut as a state of current residence or previous residence, users should not compare 2022 ACS 1-
year and 2018-2022 ACS 5-year estimates to other ACS data. The 2022 estimates will be suppressed in future 1-year
and 5-year Comparison Profiles for Connecticut and nested geographies. Affected estimates include Same county;
Different county, Same state; and Different county, Different state in CP02. For other states and Puerto Rico, users
should use caution when comparing 2022 ACS 1-year and 2018-2022 ACS 5-year estimates to other ACS data.
Data for total movers, non-movers, and movers from abroad were not affected by the error. Estimates for Place of
Work and other ACS topics were unaffected. The error did not impact population estimates associated with the
Census Bureau’s Population Estimates Program. The error did impact estimates associated with the 2022 State-to-
State Migration Flows [/data/tables/time-series/demo/geographic-mobility/state-to-county-migration.html] .
The processing error impacting 2022 has been corrected for the 2023 ACS 1-year estimates. Revised data for 2022
will be used to create the 2023 and later ACS 5-year estimates.
Page Last Revised - August 30, 2024