I guess that the BTC growth in 2018 and on the next years too depend of laws which will be created each country. While BTC and others criptos were unknown till 2017... your growth was not controled by anyone. From now on mainly in conservatives countries they will do all to get the BTC and criptos growth censured
To be frank the future of bitcoin does not depend upon some country regulating it,i would like to see it as a decentralized currency and the best these governments can do is to ban the exchanges being run n their country,these sort of news will affect the price of bitcoin as we see recently from the Korean authorities ,i only see a bright future for bitcoin when the lightening netwrok is activated.