King County's data is misleading. They admit that there are practically zero unvaccinated people in the county in the age groups at highest risk of death, and they artificially inflate their numbers. The red box on your link links to a document that describes them claiming that at least 5+% of these age groups are unvaccinated, even when they are not. Relevant quote:

"To resolve these issues, we have added a "continuity correction" to our estimates of the size of the unvaccinated population, to ensure that it would not become unrealistically small. To do this, we assume that we will not reach 100% vaccination and that at least 5% of each age group, race/ethnicity group, and zip code will always be unvaccinated."

In the last 30 days (chosen because the only other stat includes time before vaccines were available), 80% of deaths (50/62) in King County were in people over the age of 60 [1]. The dashboard in your link states that "Over the past 30 days, people who are not fully vaccinated are 24.3 times more likely to die due to COVID-19 related illness than people who are fully vaccinated" [2]. These are the number of people who have been vaccinated compared to the total population of the age group, as well as how many died in each group in the last 30 days [3]:

60-69 y/o: 218.4k residents, 218.8k vaccinated partially, 207.6k vaccinated fully, 13 deaths.

70-79 y/o: 124.2k residents, 136.5k vaccinated partially, 129.0k vaccinated fully, 17 deaths.

80+ y/o: 59.9k residents, 70.3k vaccinated partially, 65.0k vaccinated fully, 20 deaths.

Using the 24.3 times more likely to die ratio mentioned above, this means that, assuming the relative risk is constant across age groups, 2 people over 60 who died were vaccinated, and the other 48 were unvaccinated. Considering the ridiculously small population of unvaccinated people in this age group, the deaths per unvaccinated population rate (unadjusted) is insanely high, far higher than the pre-vaccine availability death rate. This does not smell right.

Also, the graphs on that dashboard (by default) aren't raw deaths divided by population; they are adjusted by age because, in their words, "when considering rates, it’s important to standardize, or control, for age. For example, older adults are both more like to be vaccinated than younger people and more likely to have underlying health conditions that may decrease the protection they get from vaccination and increase their risk for being hospitalized or dying if they get COVID". I think this is a fair adjustment to make, but King County did not do age standardization in the past, and the only dashboard that does it today is the vaccination status one. Since the number of unvaccinated people in the age groups with the vast majority of deaths is "adjusted" from the real counts, which show that there are more people vaccinated than the most recent census, it is impossible to accurately perform age standardization. There is no raw data on the site with vaccination status attached, so it is impossible to see what effects their adjustments have had.

[1] https://kingcounty.gov/depts/health/covid-19/data/daily-summ... Go to the "Demographics" tab, select "Deaths" from the drop down, and select the "Last 30 Days" radio button.

[2] Exact quote comes from clicking the "Relative Risk trend" box below the "death" ratio on your dashboard.

[3] https://kingcounty.gov/depts/health/covid-19/data/vaccinatio... Select "Demographics", and "10 year age groups" from the dropdown.