Precisely, there are a lot of external factors to consider especially with bitcoin's high volatility, thus making it very sensitive to forks, ICO prohibitions or country banning. By basing the price of bitcoins last January 2017 (which was only around $950), I estimate that bitcoin would reach $12,000-$15,000 mark by the end of next year, assuming the forks that will happen will affect it significantly. The pattern that I observed when checking the price of bitcoins is that, it decreases by 2-3 weeks prior to forks but after that, it regains its value and reaching new heights.