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?
To answer the original question :
https://blockchain.info/charts/total-bitcoins?timespan=all&showDataPoints=false&daysAverageString=1&show_header=true&scale=0&address=An yes to whoever the person was above asking whether the graph is linear. No it is NOT linear when examined closely. Having said that the last Bitcoin will be mined somewhere close to 2140. By that I mean - can't predict the exact time but possibly a range as we move closer and closer.