Yeaah, but how many folks just told the census taker, “Dude, I was born right around here somewhere about 47 years ago. I don’t know the exact date or location because we didn’t keep those records in caves and such.”
As far as I know, not a single scrap of a record of the actual census has survived, which is a little suspicious in itself.
As the barbarians stormed and burned Rome, first priority was, save the census records. /s