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The Commemorative
Quarter for
South Dakota
The Commemorative Quarter for South Dakota

The 2000 Census showed that Union County had a population of 12,584 people. This represented 1.67% of the total population of South Dakota, making it the state's 14th most populous county (out of 66 counties).

From the Census Estimates for 2009<1>, Union had a population of 14,589 people. This is an increase of 15.93% since the 2000 Census.

The following table shows the recent changes in population. Other than 2000, the population counts have been estimated by the Census Bureau.

Since 2000
Year-to-Year Change
201014,399+14.42%-1.3% since 2009
200914,589+15.93%+2.82% since 2008
200814,189+12.75%+1.47% since 2007
200713,983+11.12%+2.49% since 2006
200613,643+8.42%+2.33% since 2005
200513,332+5.94%+1.17% since 2004
200413,178+4.72%+1.36% since 2003
200313,001+3.31%+1.45% since 2002
200212,815+1.84%+1.39% since 2001
200112,639+0.44%+0.44% since 2000
200012,584The Last Census

Union County had 5,345 Housing Units<2> at the time of the 2000 Census.

The 2000 Census shows that Union County has a total area<3> of 467.1 square miles [1,209 km²]. Of this total, 460.4 square miles [1,192 km²] of the area is land, with the balance (1.44%) being water (6.7 square miles [17.36 km²]).

Using the above population and land area values, Union County had a population density of 27.33 people per square mile [10.55 people/km²], making it the state's 9th most densely populated county (out of 66 counties).

US Census QuickFacts

The Census Bureau has created documents containing demographic information that are called QuickFacts. A QuickFact that is specific to Union County is available. The QuickFact also contains a comparison between Union and the state of South Dakota.

Click here for the Union County QuickFact (QF-46127).

Below are some of the communities that are located in Union County:

(2009 Est)
(2000 Census)
Change in

Below are the counties that adjoin and form the boundaries of Union County. A link to their specific Census QuickFact has been provided.

(2009 Est.)
(2000 Census)
Change in
Plymouth (IA)QF-19149   E24,21024,849-2.57%
Sioux (IA)QF-19167   NE32,24431,5892.07%
Woodbury (IA)QF-19193   SE102,831103,877-1.01%
Dakota (NE)QF-31043   S20,65120,2531.97%
Dixon (NE)QF-31051   S6,2896,339-0.79%
ClayQF-46027   W13,49013,537-0.35%
LincolnQF-46083   N41,21824,13170.81%

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About South Dakota

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Off-the-Road Links ...

U.S. Census Bureau
Census QuickFact for Union County

Footnotes ...

<1>On a yearly basis, the US Census Bureau creates an estimate of the county's population. Keep in mind that this is an estimate and not an actual count. The last physical count was the 2000 Census and the next count will be for the 2010 Census.

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<2>A Housing Unit is a broad term for those places where people live (whether occupied or temporarily vacant), such as a house, an apartment, a mobile home, or an area that is considered as a separate living quarter. Separate living quarters (consisting of one or more rooms) are considered to be those places where people live, sleep and eat separately from others and that have access to the outside (either directly or by a shared hallway).

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<3>The area value has been supplied by the US Census Bureau and it can be different than the geographic boundaries of Union. The value given by the Census Bureau reflects their statistical (or sampling) requirements.

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<4>All Quarter-dollar coin images from the United States Mint.

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