Attached are comparison tables for race and race and Hispanic status for the 2019 and 2021 ACS. Overall the number of multi-race (two or more race households) has grown from about 11.3 million to 41.9 million between the two ACS's. Among non-Hispanic the increase is about 6 million, and for Hispanic about 24.6 million.
At this writing there is no way to reconcile the numbers or make them consistent so that one can actually look at a trend. I realize the Census Estimates Division, so far, has not adopted this approach. Much of the change in these numbers is due the decision by the Bureau to conduct a content analysis of the fill-ins for the race question answers, and for the Hispanic question. Up to 200 characters were scanned looking for evidence of other races, aside from the one checked. If such a race was found, then the person was coded into that race as well. This change in the 2020 Census handling of race and Hispanic status was ported to the ACS. However, there is no way to know, nor has such information been reported on how many individuals in what race/Hispanic configuration were shifted in this way. Nor is there any available information on what the results would have been if they had been processed, as they were in 2010, and the white and black fill-ins had not been added. In short we have no way to interpret change in race and Hispanic status over time, nor can these numbers be used for comparison purposes when the OMB mandated that other agencies along with the Census, adopted the "Check one or more races" which was first recorded in the 2000 Census.
Having this massive change with no crosswalk for either the ACS or the Census, will make it virtually impossible to do meaningful comparisons with the race and Hispanic data from all of the other sectors of society that use such data to monitor race and Hispanic disparities. This includes, the employment sector through the EEOC, the criminal justice system, the courts, allocation of housing and housing subsidies, birth and death certificates, the health system and virtually any other area that through law or custom or both require monitoring of race and Hispanic disparities. Having used the ACS in court many times to compare housting, employment or jury composition, as well as the operation of law enforcement with the underlying numbers derived from the ACS, I am personally quite concerned. Nor do I know how to give guidance to the users of Social Explorer, which include students at over 500 colleges and universities, and many users from the state, local and federal government, as well as the non-profit and business sectors.
We plan to do more work regarding this issue.
Professor Emeritus of Sociology
Queens College and Graduate Center CUNY
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