I have aunts and uncles who have lived a long time, with two of them in fine health above age 90, so I find this a bit more believable. My maternal grandmother,

I have aunts and uncles who have lived a long time, with two of them in fine health above age 90, so I find this a bit more believable. My maternal grandmother, their mother, lived to be 99. Anyway, on the issue you doubt, Vaupel and other professional demographers "show the work" in their professional publications.