Seems like going back too far (including any price movements before 2013), chronologically, would lead to increasing probabilities of error, because the BTC market continues to change in terms of the kinds of adopters and the amount of increasing adoption while BTC still remains as relatively small in terms of overall adoption. 

Furthermore, there is a certain level of added financialization complications with the increasing role that altcoins and ICOs are playing in the space (price pressures that go both ways with the influx of new money, while recognizing that there is a whole lot of scamminess going on in the alt space while a large number of them are striving for financial value by positioning themselves as a kind of bitcoin 2.0, or otherwise engaging in profound marketing efforts to denigrate BTC).