The digital currency bitcoin is currently still near all-time highs, but bullish calls remain for the asset. One investor thinks it could almost double to $4,000 by the end of 2017. Bitcoin hit an all-time high in late May, reaching to $2791.70 according to CoinDesk data, recording a 180 percent rally year-to-date. There was a subsequent price correction towards $2,100 but bitcoin currently stands around $2,468.56. The market cap for bitcoin has swelled to more than $40 billion.