Montgomery County Population - Illinois

Data Item State County
Population, 2019 estimate - (Number)
Year Value
200030,625
200130,454
200230,440
200330,176
200430,144
200529,958
200629,959
200729,789
200829,704
200929,500
201030,097
201129,864
201229,616
201329,362
201429,449
201529,192
201629,061
201728,781
201828,691
201928,414

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