(TNS) — For more than year, state officials and community groups in California have pushed a singular message: the importance of filling out the decennial count.

Organizations canvassed neighborhoods, and hosted rallies and information sessions where they explained how census data turns into federal dollars that trickle down to cities and states. After the coronavirus pandemic wiped out the chance to gather in person, they started phone banks and honed social media campaigns.

Those efforts, officials said, have achieved some of the best results in the country in getting the hardest-to-count communities to respond — of the estimated 3.5 million to 4.1 million households in that category, some 2 million have replied — although there is still work to be done to ensure a more complete count of historically underrepresented groups.

Now officials have discovered a different problem to worry about: Some affluent California neighborhoods have fallen far behind in their response rates compared with the 2010 count. "In Los Angeles, we see a low response from Malibu to Beverly Hills and even into Studio City," Ditas Katague, director of the California Complete Count Census 2020 Office, said on a Monday call with reporters. "That's concerning and alarming to us."

Although some of those regions fell below the statewide self-response rate in 2010, the roughly 36 percent response rate in parts of Malibu — and the resulting 20 percentage point gap from the last count — is "unprecedented," officials said. Katague said her office has seen a similar phenomenon in other upscale areas of the state, such as parts of Newport Beach and Carmel-by-the-Sea.

Several of the state's difficult-to-count tracts — where barriers exist to full and representative inclusion — are behind their 2010 self-response rates, such as spots in Boyle Heights and Santa Ana. But more surprising were pockets in the Bay Area's Marina, Cow Hollow, Pacific Heights and Presidio neighborhoods where there is a nearly 20-point lag in response rates, census workers said.

Officials said it isn't clear what's behind the drop in participation. But demographers have pointed to the pandemic as a major source of the problem. Some say that, as in New York City, rich Californians may have fled their homes for vacation houses. Others believe it could be that some households haven't responded because their California addresses don't represent their main residence.

"It's the Manhattan effect. It's the same thing in New York," said USC demographer Dowell Myers. "In San Francisco, people who have alternate locations shifted away from the danger, and the middle class and working class stayed put.

"The [U.S.] Census Bureau put a lot of effort into the hard-to-count areas, but they didn't plan on this other thing happening. How could they?"

The pandemic has disrupted the count in many communities, Myers said, "but you do need to sort of shock them with the consequences."

"If they don't get counted, they will get public resources diverted from their communities," he said. "There will be downward pressure on their share of the public dollars, on their share of services, on their share of everything."

The virus is affecting people's responses "regardless of economic background, regardless of political party," said Emilio Vaca, deputy director of the California Complete Count Census 2020 Office.

"What gets impacted is the social networks that people go to, and so in the hard-to-count communities, people may not be able to go to the local library or family resource center because they're sheltered in place," he said.

The state made a sizable investment in the 2020 count, according to the Public Policy Institute of California, pouring some $187 million into census-related activities since 2018.

The census office in California said it has focused its outreach on the most difficult to track households — including communities of color, those who don't have broadband internet access, people who speak English as a second language and those who live at or near the poverty line — because they have historically been at greater risk of being missed in the census.

Households in Malibu and Beverly Hills typically haven't needed the extra nudge to participate, said Diana Crofts-Pelayo, spokeswoman for California Complete Count.

"You're also seeing a potential behavior change when it comes to people's prioritization of day-to-day activity and civic engagement," she said. "If you're caring for a loved one or someone with COVID, maybe the census is the last thing on your mind."

States draw on census data to form school district boundaries, and many of the services that people rely on in California, such as nutrition programs and housing assistance, are tied to funds calculated using the census. In 2015, the most recent year for which an estimate is available, California received about $77 billion in census-related funding — "more than 80 percent of the total federal funds the state received that year," according to a report from PPIC.

In fiscal year 2017, 316 federal spending programs called on 2010 census-derived data to distribute $1.5 trillion to state and local governments, nonprofits, businesses and households throughout the country, research from the George Washington Institute of Public Policy shows. At stake are not only federal tax dollars, but also political redistricting and the reapportionment of seats that each state is allocated in the U.S. House of Representatives.

So far, 9.7 million California households have responded to the census. California's self-response rate is above the national average, at 64.2 percent versus 62.9 percent, but ranks 22nd among all U.S. states.

Those figures belie another problem with census replies, said Paul Ong, director of UCLA's Center for Neighborhood Knowledge: the high chance of a "differential undercount," in which one group is less likely to be included than another group.

"Historically, this has included low-income households, people of color, Indigenous individuals, and immigrants. There are enormous political and economic implications from a racially biased census count," Ong said.

"Marginalized populations will be further disenfranchised and disproportionately left out for public funds and services."

Ong said he believes that the country is facing a "massive problem" at this stage of the census count compared to 2010. The next phase of the enumeration, the "Nonresponse Followup Operation" that begins in most of the nation Aug. 11, will determine the size of a racial differential undercount, he said.

That process, in which census workers will begin crucial door-knocking efforts, "will face many barriers and challenges to close the looming and massive bias." Those field data collection efforts — as well as self-response options — will end Sept. 30, a month sooner than initially scheduled.

It's "certainly true" that some wealthier areas are not responding at their typical rates, Ong said, adding that he doesn't discount the issue. But to him, that's not the biggest problem.

"If we have to put in more resources in the last few months of the count, that is not my priority. It's more important to get the hard-to-count communities, because they are the ones on average really left behind," he said.

"Think about a hurricane hitting New Orleans again. You could always make stories that even rich neighborhoods have been hurt, but that narrative misses the fact that it is really the poor neighborhoods, with the least resources, disproportionately hurt."

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