Some reasons I believe bitcoin is likely to rise next time
Bitcoin is dropping sharply from $ 20,000 down to about $ 6,000 by the end of 2017, but that's a lot more than $ 2500 a year ago.
Laws gradually intervene in the market, may form the law for crypto, institutional investors can peace of mind to invest in the market
Mt Gox is allowed by law to compensate bitcoin victims for a percentage, without the need for cash compensation, which could end the sale of large amounts of bitcoin.
How do you believe bitcoin will increase from now until the end of the year?
There's no assurance yet. The market is so volatile making the market value hard to predict and make speculations. As such, holding is really advisable as well as avoiding to sell. The increase is expected to happen at the end of this year and if that so, investing now would really be a huge advantage.