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The Commemorative
Quarter for
The Commemorative Quarter for Montana

The 2000 Census showed that Yellowstone County had a population of 129,352 people. This represented 14.34% of the total population of Montana, making it the state's most populous county (out of 56 counties).

From the Census Estimates for 2009<1>, Yellowstone had a population of 144,797 people. This is an increase of 11.94% 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
2010147,972+14.39%+2.19% since 2009
2009144,797+11.94%+1.54% since 2008
2008142,602+10.24%+1.82% since 2007
2007140,047+8.27%+1.31% since 2006
2006138,239+6.87%+1.28% since 2005
2005136,493+5.52%+1.44% since 2004
2004134,559+4.03%+1.13% since 2003
2003133,054+2.86%+0.97% since 2002
2002131,771+1.87%+0.89% since 2001
2001130,608+0.97%+0.97% since 2000
2000129,352The Last Census

Yellowstone County had 54,563 Housing Units<2> at the time of the 2000 Census.

The 2000 Census shows that Yellowstone County has a total area<3> of 2,649 square miles [6,861 km²]. Of this total, only a minor amount of that area is covered by water (13.9 square miles [36 km²]).

Using the above population and land area values, Yellowstone County had a population density of 49.09 people per square mile [18.95 people/km²], making it the most densely populated county in Montana.

US Census QuickFacts

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

Click here for the Yellowstone County QuickFact (QF-30111).

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

(2009 Est)
(2000 Census)
Change in

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

(2009 Est.)
(2000 Census)
Change in
Big HornQF-30003   SE13,01512,6712.71%
CarbonQF-30009   SW9,7569,5522.14%
Golden ValleyQF-30037   NW1,0571,0421.44%
MusselshellQF-30065   N4,6004,4972.29%
RosebudQF-30087   E9,2589,383-1.33%
StillwaterQF-30095   W8,7868,1957.21%
TreasureQF-30103   NE612861-28.92%

Other Roadside Stops ...

About Montana

Visit our Community Index for Montana

Off-the-Road Links ...

U.S. Census Bureau
Census QuickFact for Yellowstone 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 Yellowstone. 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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