Over the years, I have noticed that every time Bitcoin's price goes down other alt coins follow suite. And When the price of bitcoin increases, it’s expected that altcoins go up in price shortly after.
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One of the reasons why I am avoiding a lot of altcoins these days, the percentage when the market recovers are really far from Bitcoin. I also believe that this is the power of having a high market capitalization.
If you compare to other altcoins, the percentage of dumps when whole market is dumping is very huge to altcoins and when market recovers, other altcoins pump is not too huge compared to Bitcoin.