From a record high to a sharp drop, bitcoin has recently become a roller coaster. Although there is a bubble in the price of bitcoin, more and more people believe that its investment will still pay off in the long run. Comprehensive media reported on January 12 that after bitcoin fell below US $40000 in the early morning of January 9, the price of bitcoin fell sharply again on January 11, with a sharp drop of more than 20% during the day, to US $30486, equivalent to nearly US $9000 in one day. The cryptocurrency market wiped out more than $200 billion in market value. Bitcoin rebounded at more than $4000 at $34900, according to the latest data from bitstamp on January 12. The previous week (January 4 to January 8) saw a frenzied rise in bitcoin. On January 8, according to bitstamp data, bitcoin broke through the $40000 barrier in one fell swoop, reaching a record high of $41910, just a foot in the door from $42000. Bitcoin has more than tripled in the past year. In a recent research report, JPMorgan said bitcoin could reach $146000 in the long run, as it could become an alternative currency to gold. To achieve this price, strategists point out, bitcoin must be much less volatile. But some bitcoin critics call bitcoin a bubble. Michael Hartnett, chief investment strategist at Bank of America Securities, recently said bitcoin looked like “the mother of all bubbles.”.