I would think that in early part of January 2018, many folks in the states will be selling BTCs to avoid having to pay capital gain tax in 2017 income tax return. This may be the case especially if BTC keeps trending down through the end of December, making people fear and run for the hills.

BTW just wanted to touch on BTC mania in South Korea. One does not have to pay capital gain tax gained from trading crypto currencies under the current South Korean tax law. This may be one of the reasons why the trading volume has been unproportionally high there in terms of the size of population (roughly 50 million total population in South Korea as versus over 300 million in the US).