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The Commemorative
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The Commemorative Quarter for Oregon

The 2000 Census showed that Washington County had a population of 445,342 people. This represented 13.02% of the total population of Oregon, making it the state's 2nd most populous county (out of 36 counties).

From the Census Estimates for 2009<1>, Washington had a population of 537,318 people. This is an increase of 20.65% 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
2010529,710+18.94%-1.42% since 2009
2009537,318+20.65%+1.93% since 2008
2008527,168+18.37%+1.69% since 2007
2007518,427+16.41%+1.65% since 2006
2006510,023+14.52%+2.61% since 2005
2005497,073+11.62%+2.44% since 2004
2004485,249+8.96%+1.49% since 2003
2003478,103+7.36%+1.42% since 2002
2002471,401+5.85%+1.97% since 2001
2001462,316+3.81%+3.81% since 2000
2000445,342The Last Census

Washington County had 178,913 Housing Units<2> at the time of the 2000 Census.

The 2000 Census shows that Washington County has a total area<3> of 726 square miles [1,881 km²]. Of this total, only a minor amount of that area is covered by water (2.63 square miles [6.82 km²]).

Using the above population and land area values, Washington County had a population density of 615 people per square mile [237.6 people/km²], making it the state's 2nd most densely populated county (out of 36 counties).

US Census QuickFacts

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

Click here for the Washington County QuickFact (QF-41067).

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

(2009 Est)
(2000 Census)
Change in
Forest GroveQF-412620021,44817,70821.12%

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

(2009 Est.)
(2000 Census)
Change in
ClackamasQF-41005   SE386,143338,39114.11%
ClatsopQF-41007   NW37,24335,6304.53%
ColumbiaQF-41009   N49,59243,56013.85%
MultnomahQF-41051   E726,855660,48610.05%
TillamookQF-41057   W24,88924,2622.58%
YamhillQF-41071   SW99,03784,99216.53%

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U.S. Census Bureau
Census QuickFact for Washington 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 Washington. 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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