2017 was 4th best year for Bitcoin after 2010, 2013 and 2011. You see all beside year 2014 were positive.
2010 $0.003 +10000%
2011 $0.3 +1566%
2012 $5 +160%
2013 $13 +5823%
2014 $770 -59%
2015 $316 +36%
2016 $430 +128%
2017 $980 +1286%
2018 $13585
But this is true when we think of it in terms of percentage, when we see this in terms of dollars this has been the best year so far and seems like a breakthrough year to me, a year in which bitcoin is no longer a coin known to some people in an obscure part of the internet, bitcoin is finally going mainstream and we'll see more of this in the next years.