Irvin called after the new tally showed Aurora had lost 17,215 people over the past 10 years, bringing the total population to 180,542, down from 197,757 in 2010.

In a statement Friday afternoon, Irvin said the U.S. Census Bureau’s release of these numbers “brought many questions, anomalies, and surprises, especially an extremely low population number for Aurora.”

“While Aurora remains Illinois’ second-largest city by tens of thousands of residents, a supposed reduction of 17,000 people over the past decade is questionable at best,” he said.

Irvin is asking for a review of the results through the federal 2020 Census Question Resolution Program. The mayor added that, if necessary, the city would “enact a special census request, if necessary.”

“With the significant impact of the census on federal funding and local, state and federal redistribution, there’s too much at stake if we don’t do this,” he said.

Throughout 2020, while battling a lockdown due to the coronavirus pandemic, Aurora officials lobbied for people to respond to the Census Bureau, both in questionnaires mailed to their home or door-to-door counters.

Officials pointed out that each person living in the city who is not counted would cost the city about $1,800 in lost gasoline, sales and state income taxes. These are all collected by the state and distributed to local jurisdictions based on population.

Some federal funds are also distributed based on local population figures.

Quick math shows that using this number with a loss of 17,215 to the city would cost the city about $31 million a year in taxes, or $310 million over 10 years.

City officials have worried throughout 2020 about severe undercounting occurring during a pandemic that included a long-term lockdown of people in their homes.

There was also a change during the year of the final count date, as well as a question of whether a citizenship question would be included in the census questionnaire.

Irvin said in particular that the issue of citizenship, although ultimately not included in any questionnaire, “only stoked more fear and reluctance to comply in the affected communities”.

Irvin said concern about an undercount or miscount “is growing locally and nationally.”

“We will do our part at Aurora to dig deeper into the numbers against our latest data collection and growth patterns over the past decade,” he said.

Irvin said if the city had really lost up to 17,000 people – which is equivalent to an entire neighborhood – the city would have noticed.

He said that would have manifested in things the city tracks, such as housing stock, traffic, water usage and many other data points.

Alex Alexandrou, the city’s chief executive, also said “it doesn’t make sense.”

“We would have seen a decline in services, and we’re not seeing it,” he said.

Aurora retained its distinction as the second largest city in Illinois. According to figures from the US Census Bureau Quick Facts, the largest cities in Illinois are: Chicago, 2,746,388; Aurora, 180,542; Joliet, 150,362; Naperville, 149,540; and Rockford, 148,655.