The amount of the Bitcoins that are being generated is very linear. So it should be possible to calculate when we will reach the maximum 21 million BTC to be in circulation.
Did anyone calculate this yet? When will the last Bitcoin be mined?
It's not linear, it's curved. It's 2140 when the last bitcoin can be earned from mining! And each coin has 8 decimal places so there are 2.1 Quadrillion Satoshi currency units!