Bitcoin's plummeting in price is due to the new year demand and supply trend. If you check the history of Bitcoin, during the end of the year it goes down in price up till the new year. All I see is still the same trend, we just need to be patient, it will definitely go up back. But this is the best time to buy and hold, because the price has gone down real much, if you invest now, you will definitely make huge profits when it rises back.