LOL maybe I will last until 100, just to get even with the kids! Paybacks are a bitch, kids!
Every time my youngest daughter says, 'I'll pay you back, Dad', I tell her 'Don't worry about it. That's one more Depends you get to change, when I'm old'. Which always gets a 'ewwwwwwwww' reply.
When I planned my stock up stash, I used 20 years as a rough goal. Who really knows if I'll even want to vape at that age. I have enough nic in the freezer, at my present percentage. I'm a low power MTL'er, so I have 12 single 18650 mods, and 4 mechs, 2 dozen tanks (all rebuildable). I should be able to make a pretty good dent in that 20 yr plan, if I last that long.
Hell, if I live longer, and run out, I'll switch to cigars. I'll have earned it, at that point!