Something you have to know about Market Cap!
If you ever wondered how the market cap could rise with 3 billion dollar in only half an hour and are thinking that 3 billion dollar is "new" money coming in, you're wrong!
To keep it simple I rounded the figures and made them smaller:
Let's say BTC has 17 million coins circulating at a price of $ 10,--.
The market cap would be 170 million.
At the moment that 5 BTC coins would be sold for $ 20,-- the whole market cap would double to 340 million while in reality only $ 50,-- of new money came in.
That's the reason of the big fluctuations of the Market Cap.
It's only a value, not real dollars!