The U.S. Census Bureau says it received thousands of comments after proposing major changes to the way it counts the number of Americans with disabilities and is deciding whether to finalize the plan.

The agency put forth a proposal in October to update its American Community Survey, which included substantial modifications to its disability questions.

Under the plan, the series of six disability questions would be reordered, reworded and a new question would be added to ask about psychosocial and cognitive disability as well as problems with speech. But potentially the biggest change is that rather than simply responding with “yes” or “no,” people would be asked to rate the level of difficulty they have with various functions. In order to be counted as having a disability, advocates say that the model proposed by the Census requires that a person respond to at least one question with “a lot of difficulty” or “cannot do at all.”

Disability advocates said they were blindsided by the proposal and they have warned that if it’s adopted, the new approach could lead to a 40% drop in the count for this population. That could bring huge consequences since Census figures are used to inform federal funding allocations and other decisions related to everything from affordable housing and transportation to health care, enforcing civil rights and more, advocates said.

“In short, major changes to the ACS data collection could have dramatic effects on people with disabilities’ access to critical government supports,” according to comments signed by dozens of advocacy groups that were submitted by the Consortium for Constituents with Disabilities.

The Census Bureau collected public comment on the proposal through mid-December and says it received over 12,000 responses.

“The majority of the comments cited concerns with changing the disability questions,” the agency said. “The Census Bureau is currently reviewing and considering the public’s feedback as part of the process for making changes to the ACS.”

The agency said that it will work with the Office of Management and Budget and the Interagency Council on Statistical Policy Subcommittee on the ACS to decide what will be submitted for final approval for the 2025 American Community Survey.