Sorry for the delayed response. And thanks for catching my math fail. Those numbers came from https://esb.nu/blog/20059695/we-kunnen-nu-gaan-rekenen-aan-corona

Sorry for the delayed response. And thanks for catching my math fail. Those numbers came from https://esb.nu/blog/20059695/we-kunnen-nu-gaan-rekenen-aan-corona https://esb.nu/blog/20059695/we-kunnen-nu-gaan-rekenen-aan-c..., but given it's in dutch it's probably easier to use this table that a redditor compiled: https://old.reddit.com/r/COVID19/comments/g4tqvk/dutch_antibody_study_of_blood_donors_reveals_3/fnzkn4k/ https://old.reddit.com/r/COVID19/comments/g4tqvk/dutch_antib... My bad on not including the source originally; I was on mobile and couldn't track it down (and therefore probably should have just not commented)