COVID-19 metrics for King County, WA

A more readable and more mobile-friendly version of the King County COVID-19 Dashboard.

Note that the King County dashboard has more recent data and shows more metrics. But good luck using it on your phone. 😀

Most data on this page is from the King County Department of Health, with some supplemental data from the New York Times.

Last updated 4/20/2021.

New cases

Notes:

For the shaded area, data was not available to download from the King County Department of Health.
The county’s own dashboard may have more up-to-date data on new cases.
The shaded area is filled in with data from the New York Times’s dataset for King County, scaled slightly to represent the average discrepancy between the two datasets.

Hospitalizations

Notes:

For the shaded area, some data was available to download from the King County Department of Health, but it is most likely undercounted due to a lag in reporting hospitaliations.
The county’s own dashboard may have more up-to-date data on hospitalizations.

Deaths

Notes:

For the shaded area, some data was available to download from the King County Department of Health, but it is most likely undercounted due to a lag in reporting deaths.
The county’s own dashboard may have more up-to-date data on deaths.
The shaded area is filled in with data from the New York Times’s dataset for King County, scaled slightly to represent the average discrepancy between the two datasets.

Tests

Notes:

For the shaded area, some data was available to download from the King County Department of Health, but it is most likely undercounted due to a lag in reporting tests.
The county’s own dashboard may have more up-to-date data on tests.

Positive test rate

Notes:

This plot is drawn using data from the King County Department of Health, but it differs significantly in magnitude from the county’s own “test positivity” metric. See Definitions below for more details.
For the shaded area, some data was available to download from the King County Department of Health, but it is most likely inaccurate due to a lag in reporting tests.
The county’s own dashboard may have more up-to-date data on tests and test positivity.

Definitions

New cases: Unique people receiving a positive test result each day.

Tests: Unique people receiving a test result each day.

Positive test rate: New cases divided by Tests.

Note this definition of positive test rate differs from King County’s own “test positivity” metric. It’s unclear to me how King County calculates “test positivity,” but I presume it is calculated as the percentage of total test results that are positive. This metric would potentially double-count individuals who are tested more than once.

King County’s public data download does not include total positive test results, so instead of that simple metric, I am using the definition of “positive test rate” that divides the unique-person metrics of New cases and Tests. The unique-person metric is usually much higher in magnitude than the per-test metric that is reported by the county, but the shapes of the two curves are quite similar.

See King County’s data definitions and notes for more details on each metric.

Data sources

Source	Used for	Availability	Last pulled
King County Department of Health	New cases Hospitalizations Tests Deaths	Every Tuesday	4/14/2021
New York Times	New cases (recent) Deaths (recent)	Many times per day	4/20/2021

Source:	King County Department of Health
Used for:	New cases Hospitalizations Tests Deaths
Availability:	Every Tuesday
Last pulled:	4/14/2021
Source:	New York Times
Used for:	New cases (recent) Deaths (recent)
Availability:	Many times per day
Last pulled:	4/20/2021

The King County Department of Health has the highest quality data but only updates weekly (and sometimes less frequently than that).

For recent data, I use the New York Times data which updates daily; it is noisier than the King County data but over time it tracks reasonably closely with the King County data, so it can serve as a good approximation for recent days that haven’t been reported yet by the King County Department of Health.

Source code

The code that generated this page is available in the covid-dashboard repository on GitHub.

Other resources

You may find these helpful:

Site	Notes
King County Overview Dashboard	Metrics per individual city Not very usable on the phone, but excellent on a larger screen
New York Times "Covid in the U.S."	Excellent nationwide data and per-state data Fantastic visualizations, maps, and charts Doesn’t show testing or hopsitalization data
Johns Hopkins COVID-19 Dashboard	Perhaps the most authoritative source for world-wide COVID data

Wear a mask

Stay healthy out there.