According to the U.S. Census Bureau, only 36 percent of the city's residents have returned their forms by mail so far. Nationwide that rate is 50 percent.
A low response would be expensive because every household that fails to mail back its census form by mail must be visited by a census taker.
It is a simple form that takes about 10 minutes to fill out. Yet, in the city of Chicago the census is something thousands of residents have yet to do.
For Elisa Alfonso the census is top priority. She sits on the Complete Count Committee for the city, county and state. The 36 percent participation rate in the Chicago shocks her. Alfonso says timing must have something to do with the low turnout.
"We are in the holidays, it's Passover, there's Easter, there's spring break. So the focus has not been on census. I think it's way too early for doom and gloom," said Alfonso.
Alfonso says fear is the Census Bureau's biggest challenge. Many just don't get that filling out a form is for counting purposes only .
"The information that is given to census is totally confidential. It is not shared by anyone, IRS, immigration, creditors, home owners, you name it," said Alfonso.
Alfonso says the other challenge is understanding what the census is all about. The census count determines how much federal money Chicago receives every year for the next 10 years. For every person not counted the city loses $19,000.
While city residents lag behind in returning forms, suburbs are doing much better. The city of Wheaton has the best rate in the state.
"A lot of the response is just a function of people not having fear or suspicion of sending in some of their private information," said Todd Scalzo, Wheaton Complete Count Committee.
Because of cities like Wheaton, the participation rate in Illinois is running ahead of the national average.
Here in Chicago Alfonso says the key is linking the census to the bad economy. She says people fill out the form once they understand services will be cut if Chicago is undercounted.
A big census rally is scheduled Thursday at Federal Plaza.