It almost reached 19800$ on coinbase a week or two ago and then it crushed done to 13k$, but this is complete normal.
It was an unnatural movement, and for that reason not sustainable, so it shouldn't carry too much weight. GDAX has some very wealthy entities trading there, where even in current market they have the ability to use their deep pockets to steer the market in their preferred direction. It was a great money making opportunity, that's how I look at that peak.
I wanted to buy when it was 1000$, I was on vacation and decided to buy when I come back but then it was already 3K$ now we are talking about 20k$. It's insane
It just shows that this market doesn't allow any entity to sit back and think or 'analyze' everything before buying. We have seen that waiting 24 hours, which in reality is nothing at all, can still result in the price having increased another $1000-$1500, which is pretty insane. In other words, pull the trigger and don't waste time waiting for whatever opportunity or other reason. Today the price is nearly $19,000, where a few days away from now we could be heading towards $25,000 - it's a crazy market.
The floor now is $16k to $17k dollars and the ceiling will be $20k dollars. This price rising have advantage and disadvantages but I'm being optimistic about it. 
