I think every investor who had invested at BTC peak value is now 90% loss if he still hold and i think maximum investor still holding the coins and hope as market recovers they will also recover there losses.
The computation is wrong, the peak let's say was $20,000 and the current price now is $5,000, so it should only total to 75%.
90% I'm sure will apply to losses in altcoins coins as they dropped harder.