https://www.yahoo.com/news/everyone-crazy-ethereum-bitcoin-still-001530800.html

Predicting the future appreciation of Bitcoin is difficult. As we have seen over the past couple of years, it can tumble back down following major world events. China’s decision to ban financial institutions from using Bitcoin in 2013 saw the currency nearly halve in value over a few weeks. Hacks of major Bitcoin exchange services, and speculative bubbles, have led to other temporary downturns in its fortunes.