That's a pretty lazy answer. Why not last year, or the years before? Bitcoin is nearly 10 years old and monetary policy has been "easy" that whole time (in the US and Europe). Why is it taking off this year in particular? What is the deal with the slew of ICOs? I am not sure what you mean by compound interest. Are you trying to make a pun, e.g. compound hype or referring to financial interest rates?