These data aren't considering absolute numbers at all: they're "positivity rates", meaning that the size of the group measured does not matter. So yes, not vaccinated individuals have the lowest incident RATE of COVID-19 positivity among all groups from 4/14 through 4/20. If you look at 100 people or 1,000,000 people, the rate stays true: the not vaccinated showed the fewest % of people who had a positive COVID-19 result.
These data aren't considering absolute numbers at all: they're "positivity rates", meaning that the size of the group measured does not matter. So yes, not vaccinated individuals have the lowest incident RATE of COVID-19 positivity among all groups from 4/14 through 4/20. If you look at 100 people or 1,000,000 people, the rate stays true: the not vaccinated showed the fewest % of people who had a positive COVID-19 result.