When city officials took on the herculean task of getting every New York City household to fill out the census, an eat-your-vegetables exercise that provides millions in federal aid to low-income residents, they didn’t expect the Upper East Side to pose much of a problem.

But the coronavirus has upended census-takers’ best-laid plans. And that may have serious financial implications for the city.

Only 46 percent of Upper East Side households have filled out their census forms, according to a June 25 report circulated by the Department of City Planning’s chief demographer, Joseph J. Salvo — well below the neighborhood’s final response rate in 2010, and short of the current citywide rate of almost 53 percent.

The reason?

“They’re not here,” said Liz Krueger, a Democratic state senator, referring to her constituents in Midtown and the Upper East Side. “No one’s here.”