There are a lot of factors influencing the price of bitcoin, including technical issues/new alts coming out/regulations/stubborn miners/conflicts between developers(or groups)...etc.
What do you think is the most crucial cause? Why did the price drop dramatically these days? Will this be a rebound point?
In my opinion, the biggest impact on the market is the actions of big fish that can manipulate the market due to the large number of coins they hold. This is my point of view.
