The following document is a collection of data, tables, and graphs highlighting the results of the 2010 Census. The data, which was collected by the Census Bureau during 2010, was first released in terms of National ad state population totals in December 2010. After this initial release, the Bureau has periodically released additional data with further detail.

Redistricting data, which included additional state, county and local counts, was released in February 2011. In May 2011, demographic profiles were released, which identified population and housing characteristics from a state-by-state and county-by-county perspective. In June 2011, specific population data specific to race were released and broken down by geographic location. Although additional 2010 census data will continue to be released by the U.S. Census Bureau over the next few years, the Commission has taken the data currently available and compiled it into an Illinois specific demographic report.

One of the most important aspects of the U.S. census is that the new population figures determine the number of seats a state occupies in the U.S. House of Representatives. While Illinois' population grew 3.3% between 2000 and 2010, the increase was below the national average growth of 9.7%. As a result of the shifting population base, Illinois' number of apportioned U.S. representatives was reduced from 19 to18.