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2020 census
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Washington is 10% more diverse than it was 10 years ago. What does that mean?

There is a 56% chance that if you picked two people at random in Washington state, they would be from two different races or ethnicities —that's one takeaway from 2020 census data released by the United States Census Bureau on Thursday.

In Washington state, the population grew 10 percentage points more diverse compared to a decade ago, according to a census metric called the diversity index.

This is the probability that if two people are picked at random, they will be from two different races or ethnicities. The Census Bureau uses the metric to track and compare a region's racial and ethnic diversity since the last time a census was taken.

You can explore an interactive map comparing racial and ethnic diversity in the U.S. using data from the 2010 and 2020 census here.

Where diversity increased in Washington

Washington's diversity index was 45.4% in 2010, and jumped to 55.9% in 2020.

Many of the counties that saw an increase in their diversity index are located in western Washington — like King, Pierce, and Snohomish counties.

caption: Demographic information for King County from the 2010 and 2020 U.S. Census. 
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But other parts of the state also showed increases, like Okanogan County, which went from a diversity index of 49% in 2010 to 55.1% in 2020.

In other areas, populations flipped —take Yakima County for example.

The last time the census was taken, white county residents made up 47.7% of the population in Yakima County, and the Hispanic/Latino population was 45%.

But 2020 census data shows that while the white population dropped to 40.3%, the Hispanic/Latino community rose to 50.7%. That increase now makes the Hispanic/Latino community the largest racial or ethnic group in Yakima County.

Washington's overall population increased by 980,741 people between 2010 and 2020 — a 14.6% change. According to the 2020 census, Washington now has about 7,705,281 residents.

King County's population grew the most over the past decade — by 338,426 residents. About 100,000 of those new residents moved to Seattle, according to The Seattle Times.

United States

Scroll through the interactive map below for details, or check it out here.

The latest census results also indicate that the U.S. population is the most diverse it's ever been.

"Our analysis show that the US population is much more multiracial, and more racially ethnically diverse than what we measured in the past," said Nicholas Jones, director for race, ethnicity and research for the Census Bureau.

Over the past decade, the number of white people in the United States fell for first time since 1790.

But there are questions surrounding the reliability of the demographic data.

Census methodology changed for 2020 to let people self-identify their race and ethnicity. It's not yet clear how much that change affected these census results. However, the Census Bureau's Acting Director Dr. Ronald Jarmin shared in a blog post that an early data analysis revealed a higher rate of households did not answer the race and Hispanic origin questions in the 2020 Census in comparison to past counts.