368 exchanges have closed down since 2014, and 161 of them "just vanished". Trust no exchange with your money: A glimpse on the Exchange Graveyard.
We often remember Mt. Gox or the most recent fiasco when it comes to exchanges going down, but there are a lot more cases and these melt downs are common than I had thought. I got some data from Cryptowisse
Bitcoin Holders and Everything Related to Criptocurrency by Some Important Web Pages at This Time
New Zealand: Financial Authority Blacklists Another Three Crypto Platforms Marked as 'Suspected Scams' Greetings. News highlighted by some important web pages ccn.com tells us; 1) FATF: UK Crypto Exchanges