and whenever bitcoin has bad days with big dumps, the altcoins get dumped one more time too.
here is the palpable example of the dump that happened because of bitcoin price going down.
you can clearly see that altcoins have been dropping hard today. and both against bitcoin and USD.
here is their stats against bitcoin:
and here is the stats against USD. and here you can see how the drop of altcoins is much bigger than drop of bitcoin.