I think no stock gives that return in 21 months. BTC has a lot way to grow yet, but as htey say, nothing is certain. I will be cautious with investment although every tendency shows that this is going upwards
Well thats true although btc has a potential and possibly can give good return if you invest, still everything is uncertain and its better dont expect too much.
Although i believe that btc can give nice profit, i wont invest the money that i cant afford to lose so if something bad happen with my investment im prepared.