The American Community Survey (ACS) makes use of the Population Estimates Program’s (PEP) official population estimates as survey controls in order to improve the ACS estimates for those characteristics which overlap with the PEP. This results in ACS estimates being equal or similar to the PEP estimates for total population as well as having similar age, sex, Hispanic, and non-Hispanic by race distributions. In addition, the ACS estimates for the total group quarters population are equal to the PEP estimates at the state and national level.

As part of an ongoing series of user notes that explain the effects of the population controls on the ACS for 2020 and 2021, this note focuses on changes to the methodology used for the Vintage 2022 PEP estimates which the 2022 ACS products use as its source for control totals.

It should be noted that the PEP, in an effort to improve their group quarters population estimates, revised the methodology used to produce the Vintage 2022 estimates. This year’s estimates mark the first use of the 2020 Census group quarters (GQ) total population by facility type information into the blended base. For more information on how the PEP's use of 2020 Census data was modified see the Vintage 2022 Release Notes. The result of these changes should yield better population estimates for the major GQ types than those resulting from updates to the 2010 Census base that were previously used.

To illustrate the impacts on the 2022 ACS, we provide a summary table below showing the ACS 1-year estimates for 2019 and 2021 which used controls that were not informed by the 2020 Census GQ information, the 2020 Census counts, and the 2022 ACS 1-year that uses the updated Vintage 2022 controls. Users should take these methodological changes into account when interpreting the ACS data, particularly when making year-to-year comparisons.