"People who have received at least one does by race/ethnicity" is computed differently from "People who have received at least one does by age and gender...", which appears right next to it and is worded in approximately the same way.
For example, for Pima county, if I hover my mouse pointer over "24.0% printed next to "less than 20 years", I get the explanatory note: "59,970 people have received at least one dose/250,118 population aged less than 20 years". However, if I look at "Black or African American, non-Hispanic", it says "13,414 (2.0%)", and there is not further information provided by hovering over it. Apparently the percentage is the number of people who are Black, etc. who received at least one dose divided by total population that has received at least one dose, 662,164 (x100), not divided by the number of people who are Black, etc. but it might give that impression (i.e., that only 2.0% of the Black, etc., population have received the vaccine) to someone who just glances at the data (nevermind that it would mean that over 600000 residents are Black, etc.; someone might not notice that at all, or someone unfamiliar with the county might not notice that is implausible).