From where did you even find your source?

Bitcoin's price would go most likely around 7000$ from This January to March then the prices can bounce back again to it's ATH depends on what is happening. as more and more Bitcoin users would adopt to Lightning network and Segwit the faster the transactions = more users and demand because of the fast network. one of the biggest reason why BTC's price really went down is from regulation and transaction speeds most of the holders sold their BTC just to just some altcoins that has faster tx time.

Don't worry Bitcoin's price would be back in no time posible to reach new ATH this year.