Will County Population - Illinois

Data Item State County
Population, 2019 estimate - (Number)
Year Value
2000508,038
2001531,215
2002555,566
2003580,392
2004608,245
2005631,397
2006656,075
2007670,013
2008679,069
2009685,251
2010678,824
2011680,827
2012682,477
2013683,734
2014685,158
2015685,877
2016688,328
2017690,479
2018691,149
2019690,743

Sources: U.S. Census Bureau, Population Estimates Program (PEP), updated annually. Population and Housing Unit Estimates

Definitions:

The Census Bureau's Population Estimates Program (PEP) produces estimates of the population for the United States, its states, counties, cities, and towns, as well as for the Commonwealth of Puerto Rico and its municipios (county-equivalents for Puerto Rico). Additionally, housing unit estimates are produced for the nation, states, and counties. The timing of the release of estimates varies according to the level of geography. See the Schedule of Releases for more information.

Resident Population - All persons who are "usually resident" in a specified geographic area. For the United States, the resident population includes all persons who usually reside in the 50 states and the District of Columbia, but excludes residents of the Commonwealth of Puerto Rico and the Island areas under U.S. sovereignty or jurisdiction (principally American Samoa, Guam, United States Virgin Islands, and the Commonwealth of the Northern Mariana Islands). In addition, the U.S. resident population excludes U.S. Armed Forces overseas and civilian U.S. citizens whose usual place of residence is outside the United States.

Estimates Base - The population count or estimate used as the starting point in the estimates process. It can be the most recent updated Census count or the estimate for a previous date within the same vintage. (The vintage year (e.g., V2019) refers to the final year of the time series). The April 1, 2010 Population Estimates base reflects changes to the 2010 Census population from the Boundary and Annexation Survey (BAS) and other geographic program revisions. It may reflect changes from the Count Question Resolution program. Click on the "Scope and Methodology" link for details for each vintage year.

Population percent change - The difference between the population of an area at the beginning and end of a time period, expressed as a percentage of the beginning population.

Methodology for U.S. and Puerto Rico