I bought BTC back in 2012 and 2013 and after riding the $1200 rollercoaster decided to sit back and hold instead of actively trade. I transferred most of my coins to a cold storage but left a few in exchanges such as Mt Gox and Cryptsy (and others which still exist).  I am interested in determining how much was left in the exchanges which went insolvent. Is there a way to track this for exchanges which you can no longer login to? I have the addresses which I sent coins to in my history, but I am unsure what exchange accounts those addresses are associated with. Is there any way to track this just from the address, or did all that information disappear when those exchanges collapsed?