Lawmakers and community advocates were in Glen Cove Tuesday to express concern about getting an accurate count on the 2020 U.S. census.

The results of the census count determine how much federal aid goes to help things such as highway funding, Medicare, Medicaid and special education grants.

In the previous census, about 20% of Long Island was not counted. That meant hundreds of millions of dollars in lower federal funding grants.

"If we don't get a proper count, we are not gonna get our fair share," says Nassau County Executive Laura Curran.

In 2010, 23% of Nassau County residents didn't initially respond to the census. In Suffolk, 24% of residents didn't participate. The undercounting meant that Long Island lost out on hundreds of millions of dollars that would have went to public programs. In some cases, the slack had to be picked up by taxpayers.

"New York is one of 12 states that stands to lose representation if we have an undercount," says Rebecca Sanin, of the Health and Welfare Counsel of Long Island. "Many of us would agree that we cannot afford to lose any representation in Washington D.C."

There had been a push to add a citizenship question to the 2020 census, but it failed. Pilar Moya, who works with immigrants and the Latino community, says there are many people who are still afraid of being counted.