John, OTOH consider the outcome of testing 92% of the crew assigned to the aircraft carrier USS Theodore Roosevelt...the number of Negative tests in that sample population is about 84%, and the number of Positive tests in that sample population is about 16%. So the 84% testing Negative is from a tested population largely confined to sea duty with each other! Of the 16% who tested Positive from the USS Roosevelt, 55% of that group were asymptomatic.
Every isolated sub-population is going to have a different rate of interaction and different level of conscious mitigation. Also, do we really know that some people aren't "bulletproof", in the sense that the virus is put down by the innate immune system before the virus can leave any evidence of its short history? If such a group of people exist, they play a role in herd immunity statistics, too, because they will show no evidence that they have had the disease, but are innately non-vectors, just like those with antibodies, and are already at the best possible end-state, for all intents and purposes. If that is the case, the real question is not what percentage of the population is infected or has antibodies, but what percentage don't have a good chance of being carriers, for any reason.



