On July 2017, price of bitcoin was around $3000, in December 2017, Bitcoin got the new ATH of $20000, therefore, I think it's possible to reach $30k by the end of this year.
However, it should be borne in mind that now is not 2017 and the situation is different now, including that many still remember the consequences of the rise in Bitcoin prices at the end of 2017. Now we traditionally have a decline in business activity of the cryptocurrency market until the beginning of autumn. From September we expect good Bitcoin growth by the end of the year. The achievement of Bitcoin prices by the end of the year to $ 20,000 this year, in my opinion, is not realistic, it is possible next year.