These days it seems like altcoins are doing better than bitcoin because pretty much all of their prices are green while bitcoin price is red. its because bitcoin act as aa bridge to buy and sell altcoins, that contributes a big factor.
The impact of bitcoin on the market is so high that all other coins are under its influence. Look at the price charts again and you'll see how the altcoins are moving towards the price of bitcoin. The charts are very similar to each other.