'In the US, Newman finds that the outstanding predictor of longevity is patchy birth records. Introducing proper records in the late 19th century reduced by more than two-thirds the number of babies who would eventually seem to reach the age of 110. That suggests that, until recently, seven out of 10 apparent supercentenarians were, in fact, younger than claimed.'

https://www.ft.com/content/912c2b53-65eb-4c5c-96d3-605f8872dbbe