New census data show King County continuing on a path toward greater racial diversity as its population booms to nearly 2.19 million people.

Share story

King County’s population has grown at a record-breaking pace this decade, but we haven’t just grown in number. We’ve also become more diverse.

New census data show that last year may represent a milestone in the county’s move toward greater diversity.

For the first time, people of Asian descent made up the majority of population growth in King County, increasing in number by more than 19,000 from July 1, 2016 to July 1, 2017 — that’s nearly 59 percent of the county’s 32,700-person growth for the one-year period.

Also a first: King County’s Latino population represented the second-largest share of the growth — 18 percent, or an increase of about 6,000 people in 2017.

Black people made up 10 percent of the county’s growth, multiracial people about 7 percent and white people 5 percent. People of Native Hawaiian or Pacific Island descent comprised 1 percent of the county’s growth. The Native American/Alaska Native population had a slight decline in number last year.

People of Asian descent have made up an increasingly large share of King County’s population growth each year of this decade, starting at 35 percent in the 2010 to 2011 period. But until last year, that number had remained below 50 percent.

To be sure, a major factor is the rapid growth of the tech industry, which has drawn thousands of newcomers to this area and catapulted software developers into the No. 1 spot among all occupations in Seattle. And according to data from the Bureau of Labor Statistics, one out of three software developers in the U.S. is of Asian descent.

The new census data only show the net population change, without breaking down the components of that change. So, for example, we don’t know how many people moved into King County versus how many moved away. We also can’t say how much any racial or ethnic group grew from international migration as opposed to people moving here from within the U.S.

Even so, earlier releases of census data show that King County attracts a significant number of people from Asian countries each year — in 2016, for example, about 12,000 people. So it’s likely that a relatively large percentage of last year’s growth in the Asian population was due to international migration.

But there’s more to this story of demographic change. The new census data also reveal a marked slowing of the growth of King County’s white population.

In the first year of the decade, the white population increased by more than 11,000, and represented one-third of the county’s growth. The numbers have been steadily dropping since then, and last year, the white population increased by only 1,600, or 5 percent of the growth.

And with that slowdown, King County had its smallest population increase so far this decade. Last year’s population gain of 32,700 is down by about 5,600 from 2016.

The reasons behind this change aren’t clear. And we can’t tell from the new data if fewer white people are moving into King County, or if an increasing number are leaving. Or perhaps it’s some combination of both.

The number of births and deaths also affects population growth, but that doesn’t appear to be a significant factor behind the declining rate of growth for King County’s white population.

While King County is becoming increasingly racially diverse, white people still represent the majority, at 60 percent of the population in 2017. Even so, that’s a significant drop from the start of the decade, when 65 percent of the county’s population was white.

King County is now home to nearly 2.19 million people, according to the new census data. King ranks as the 20th most-populous U.S. county, up from the 22nd spot in 2010.