There are at least
614 known altcoins. To keep an altcoin alive and tradeable, there must be a few miners and a blockchain. For how many of those altcoins has the infrastructure died? Voyacoin, for example, was
launched in February 2015 and was dead by May.Market cap above $1B - 1 coin.
Market cap above $100M - 2 coins
Market cap above $10M - 8 coins.
Market cap above $1M - 32 coins.
Market cab below $1M - 572 coins.
Most of the ones below $1M have no market. But are their blockchains still live? Or did they stop paying their
blockchain hosting bill.Some of them are still active and others are gone.
If you look at your example, voyacoin, according to coinmarketcaps, they are receiving trade data from C-Cex.
Here is a link:
https://c-cex.com/?p=voya-btcSo even though the blockchain reader is gone (not being paid for or whatever), it is still being traded on that exchange.
As long as one single miner is still mining the coin, there is a blockchain, but there might not be a blockchain reader around anymore.
In the past, when I traded altcoins (which I was very unsuccessful at), altcoins would die off everyday.
Exchanges would usually advise the users that a altcoin's blockchain is dead (hard forks or no miners) and freeze the trades, till it was fixed.
If it was fixed. Many altcoins are scams/pump&dumps/etc.
If the infrastructure for a coin is totally dead, it is usually de-listed, especially on coinmarketcap.
So if you see 614 altcoins currently, it is possible they are still active in some sort of way. But ultimately are slowly dieing.
Edit: spelling