The shingles virus just secretly and quietly lives in the body for many years until something suddenly upsets it, usually after a person is around age fifty; it particularly gets agitated if people are in their seventies and even eighties but there are many recorded cases of people who were in their sixties and a little less so, and only in their fifties. Some get shingles when they are over ninety but fewer people are alive at that age so you would have to look at per-capita statistics (per head count) to know what the percentage index would be for that age group and as to how it would compare with other age groups. It would be somewhat high. All these age groups would not have had access to the chickenpox immunization, when they were young. It was not around when some and certain people were in school or were getting their shots, when they were very young.