yeah, this is just my quick study. It is a bit shocking but also check what happened with Ethereum recently. Massive hack on one of the wallets. They actually had to hack them self to prevent from further loses. Remember that crypto is all about protecting yourself, it is very dangerous world. Check it: http://uk.businessinsider.com/report-hackers-stole-32-million-in-ethereum-after-a-parity-breach-2017-7?r=US&IR=T
RE: A history of bitcoin hacks