So it is the Holiday season and it was Xmas. How many people dived into their Bitcoin hoard to buy Xmas gifts and also paid for a nice holiday with their family?
We saw a huge increase in the price, early in the season and this might have triggered a situation where people rewarded themselves with some "Gifts" for the holiday season.
The direct impact of that would have been a higher influx of coins onto the exchanges and if that was not met with a higher demand for coins, then it would explain the drop in the price.
Did you splash out with some expensive gifts and extravagant holidays with your bitcoins, during the holiday season?
I believe that the whales are the reason why the price of bitcoin dipped down. Including those small investors in order to have food and gifts during Christmas. We also expect that in upcoming New Year celebration, the bitcoin price will move down also. That is just my guess.
I think whales are the reason too.
I don't have any tehory and any reason, but my thoughs about what happened is a market movement.
Altcoins had the best value on ≈ May, June, July (spring) and Litecoin is the first coin to recover the same level of those dates (≈ 0.19btc on July) only in 11 days.
Other altcoins had an increment these days (sc, xrp, xem, zcash...) it's like altcoins could/try recover its old value on 2018.
I though that btc will rises to $25k until genuary/february and 2018 will be the bloody year, falling until $6k - $8k
Maybe is a casuality, but one month before to the fall, there were a lot of news about a study, here there is one of those links:
https://www.coindesk.com/survey-plurality-of-bitcoin-users-think-it-can-change-world/They said this value: $196,165.79
On 16 December btc closed on ≈$19,223
Maybe, 2018 will be the altcoin's year.
No Xmas, no taxes, only a movement.