No census has been perfect. COVID-19, Trump officials' interference and the Census Bureau's new privacy protections have raised concerns about the reliability of demographic data from the 2020 count.

Transcript

NOEL KING, HOST:

Today, the Census Bureau will unveil the most up-to-date portrait of what the United States looks like. It's a portrait made up of the information collected from last year's national head count. And these numbers will give us a look at changes that are expected in the racial and ethnic makeup of this country. NPR's census correspondent Hansi Lo Wang is here. Good morning, Hansi.

HANSI LO WANG, BYLINE: Good morning, Noel.

KING: What information should we be getting today?

WANG: We're getting new population counts for local communities, the size of their adult populations, numbers of people living in college dorms, prisons, other group living quarters, plus the racial identities of people around the country and whether or not they identify as Hispanic or Latino. You know, it's the basic demographic information political map-makers need to redraw voting districts and prepare for elections for the next decade. But, you know, this census data will be getting a lot of attention because it gives us a portrait of the diversity that makes up the United States. And it's important to remember, no census is perfect. And the picture it gives us about the country's residents has always been flawed going all the way back to the first U.S. Census more than 200 years ago.

KING: Perfection would be near impossible because counting every person living in the United States is just - wow - like, a task. But then, last year in particular was a very different kind of year.

WANG: It was a very different kind of year for the Census Bureau. That pandemic upended its plans for door-knocking, that in-person outreach that's been key to getting immigrants, renters, rural residents, people of color, other historically undercounted groups counted. And there was interference from former President Donald Trump's administration. You know, leading up to the count, there was that failed push to add a question about U.S. citizenship status to census forms. And then during the census last year, Trump officials cut short the time for counting just as the bureau was making a big push to reach those historically undercounted groups through door-knocking. It was just a tumultuous national head count. And now this data we're getting, the bureau says it is high quality and, quote, "fit to use for redistricting." But all of those challenges have raised concerns about how reliable the data is, especially about race and ethnicity.

KING: How might that affect the numbers that we see today on race and ethnicity?

WANG: Well, the thing to keep in mind is census data, like other data, does not just appear out in the world waiting to be gathered, it is produced through a series of decisions. And decisions by the Trump administration, plus the conditions during the coronavirus pandemic have - could have contributed to an undercounting of Black people, Latinos, Native Americans, groups that were undercounted in the 2010 census, according to the bureau's estimates. Now, we're not going to get undercounting rates for the 2020 census and overcounting rates until early 2022 from the bureau. So we'll have to see.

But the bureau has said that for last year's census, there was a higher rate of households not answering the race and ethnicity questions than in past counts. That means the bureau had to fill in those blanks with government records, interviews with neighbors or educated guesses through a statistical technique called imputation. All those alternatives could have skewed the race and ethnicity data. And, you know, I have to mention, the Trump administration also stalled on approving some policy changes that would have allowed the 2020 census forms to collect more accurate data about Latinos, plus information about people with roots in the Middle East or North Africa. So we're going to have to live with those choices baked into this data.

KING: Is the implication, then, Hansi, that we are essentially getting an inaccurate picture of this country's demographics?

WANG: You know, we'll have a better sense as more researchers around the country look into the data, especially about local communities. But one thing I should point out is that the demographics of some neighborhoods and rural areas may be intentionally obscured by the Census Bureau's new privacy protection system. It's a way to keep people anonymous in this data. And the bureau has warned data crunchers that they may see some unusual situations because of the statistical noise the bureau has added to data about certain neighborhood blocks to make them look fuzzy. And the bureau says that fuzziness disappears when you're looking at larger areas. But I should note, this has been a very controversial move. And that - I'm seeing how the public reacts when they get - hold this census data, especially in rural communities.

KING: So much beyond just the count. NPR's Hansi Lo Wang. Thanks, Hansi.

WANG: You're welcome, Noel. Transcript provided by NPR, Copyright NPR.