Dr. Bill O’Hare’s report shows the PEP blended base being used for the 2021 and 2022 post-census population estimates corrects most of the high 2020 Census undercount for young children. In both numeric and percentage terms, the difference between the DA middle series estimate and the PEP blended base are much smaller than the difference between the DA middle series estimates and the 2020 Census estimated counts for ages 0 to 4.
The PEP blended base is also helpful in correcting the net Census undercount for the population age 5 to 13. For ages 14 to 17, there is little difference between the Census counts and the PEP blended base estimates.
This analysis shows one clear benefit of using the new PEP blended base rather than relying on the 2020 Decennial Census counts for the population base used in the Census Bureau’s yearly post-census estimates.