My dad was born in 1910 so he would have been 100 last month. He used to talk about having a birthday yardstick that moved back as well as forward. Let me explain. If he would have been 100 now, he would have been a -100 in 1810 etc. Looking back, his birth was as close to the time of Napoleon and the Adams brothers from Massachusetts, Jefferson was alive..and the Louisiana Purchase was just a few years old.
Today my negative day takes me back pretty close to the middle 1880s...actually the year my grandmother was born.
It isn't bad, considering the alternative.