Market Cap in 2018 ?

If the market cap growth in 2018 at the same rate as in 2017 means maket cap wil reach 20.390.263.150.125 $ by the end of this year. A marcket cap of 20 trillion $ seames totally out of reach right now but according to The Money Project (http://money.visualcapitalist.com/all-of-the-worlds-stock-exchanges-by-size/) 69 trillion $ are invested in the 60 largest stock exchanges and the largest stock exchange in the world NYSE has 18.5 trillion $ in investments. This is if cryptocurrencies only will replace stocks in the future but crytocurrencies are more they are money, contracts and a whole new way to see the concept of money. That this is going happen in the next year is very doubtful especially because ctyptocurrencies exploded in 2017 but that market cap will reach 20 trillion $ at some point is getting more and more likely every day.