It has been a very very bad year for bitcoin and all altcoins because of the December bull gold rush. I mean it was December and in 2017 so when you look at the 2018 prices all together we see a downtrend and everything going down. If by all means the coins go back up to their all time high levels on January 2019 we can say that 2018 all was a bad year and we wouldn't be wrong however lets not forget December is like the last month of the year so it was ALMOST 2018 when we hit the ath levels in crypto currencies.