2025 Compare Cities People:
Altadena, CA vs Mercer Island, WA

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Highlights
- Mercer Island is 0% more densely populated than Altadena.
- People are 29.8% more likely to be married in Mercer Island.
- The Median Age is 1.6 years older in Mercer Island.
 Altadena, CAMercer Island, WAUnited States
 Population  Unlock25,506329,725,481
 Female Population53.0%  Unlock50.5%
 Male Population47.0%  Unlock49.5%
 Median Age  Unlock45.538.4
 space3
 Population - 201045,446  Unlock309,327,143
 Population - 2000  Unlock22,036285,036,114
 Population - 199042,658  Unlock251,960,433
 Pop. 2000 to Now  Unlock17.6%15.6%
 Pop. 1990 to Now4.6%  Unlock30.8%
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 Population Density  Unlock3,995.993.4
 Land Area8.5  Unlock3,531,905.4
 Water Area  Unlock0.0264,836.8
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 Est. Total Population By Age
 Altadena, CAMercer Island, WAUnited States
 Age 0 to 45.4%  Unlock5.9%
 Age 5 to 9  Unlock7.3%6.1%
 Age 10 to 145.8%  Unlock6.6%
 Age 15 to 17  Unlock4.3%3.9%
 Age 18 to 202.6%  Unlock4.0%
 Age 21 to 24  Unlock2.9%5.2%
 Age 25 to 3411.8%  Unlock13.8%
 Age 35 to 44  Unlock11.8%12.9%
 Age 45 to 5414.7%  Unlock12.6%
 Age 55 to 59  Unlock7.9%6.7%
 Age 60 to 646.8%  Unlock6.3%
 Age 65 to 74  Unlock10.4%9.6%
 Age 75 to 846.1%  Unlock4.5%
 Age 85 and over  Unlock3.8%1.9%
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 Race
 Altadena, CAMercer Island, WAUnited States
 White39.5%  Unlock59.4%
 Black  Unlock0.8%12.2%
 Asian5.3%  Unlock5.6%
 Native American  Unlock0.1%0.6%
 Hawaiian, Pacific Islander0.1%  Unlock0.2%
 Other  Unlock0.7%0.4%
 Two or More Races5.6%  Unlock3.2%
 Hispanic  Unlock3.2%18.4%
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 Marriage & Family
 Altadena, CAMercer Island, WAUnited States
 Married Population49.8%  Unlock49.8%
     Currently Married  Unlock64.3%48.0%
 Married but Separated1.8%  Unlock1.8%
 Single Population  Unlock35.3%50.2%
 Never Married32.2%  Unlock33.8%
 Divorced  Unlock7.9%10.8%
 Widowed6.6%  Unlock5.6%
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 Household Size  Unlock2.602.60
 Households14,789  Unlock124,010,992
 Family Households  Unlock6,90380,755,759
     Married couple, w/children28.9%  Unlock30.5%
     Married couple, no children  Unlock48.1%42.9%
 Non Family Households4,036  Unlock43,255,233
     Single householder, w/children  Unlock4.6%15.8%
     Single householder, no children14.7%  Unlock10.8%
Reviews for Altadena    1 Reviews

I live just above the 1500 foot elevation at the edge of the San Gabriel Mountains in the L.A. suburb of Altadena--just above Pasadena. We're above the low morning fog  More

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Reviews for Mercer Island    4 Reviews

Mercer Island is a wonderful family community. It feels much more "small town" than a city even though it has a population of 20,000+. People say hello and watch out  More

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Mercer Island is a suburb of Seattle, located on an island in Lake Washington. The best thing about Mercer Island is its strategically central location relative to the  More

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Mercer Island is a suburb of Seattle, located on an island in Lake Washington. The best thing about Mercer Island is its strategically central location relative to the  More

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Start Your Review of Mercer Island


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