Thanks for posting this. Mine nic stockpile will last me about 54 years according to this. But I think I can get more from it.Look up vapocolypse calculator (excellent) it will do your figuring for you using microsoft excel .
Or the same without excel here - e-liquid Scripts - Vapocolypse Calculator
Thought i had bought enough also some years back as well.
I bought 3L of 100mg nic and vape about 5ml a day but I vape some 3mg and some 6mg. And since I don't vape the 6mg as often, one 120ml bottle I make might last me an entire year.