Never thought someone had done the actual maths on that but well done,
Believe it or not, Satoshi and Hal "did actual maths" before bitcoin was finalised, figures were not picked out of thin air. (Well, any more than the governmental reports they might have been based on were anyway)
I didn't realise that but it's nice to know, just increases my faith in Bitcoin and cryptocurrencies even more, I am so looking forward to next year