Bitcoin in 2017

2017 was the year bitcoin broke into the mainstream. It started the year below 1,000 dollars and finished near its December record, a move fueled by new retail buyers, the ICO boom on Ethereum and heavy media attention. Under the surface it was also the year of Bitcoin's biggest governance fight. The block size debate ended with two outcomes: a group of miners and businesses split off to create Bitcoin Cash on August 1, and the rest of the network activated SegWit on August 24. In December, CME and Cboe launched regulated bitcoin futures, which let large investors bet on the price, including betting against it. The peak marker shows the highest daily close of the year in our price series. A long bear market followed in 2018.

Bitcoin Cash hard fork Aug 1, 2017

For years the Bitcoin community argued about how to scale. One camp wanted bigger blocks so more transactions fit on chain. Another preferred SegWit and second layer systems. On August 1, 2017, at block 478,558, the big block camp split off with a hard fork and created Bitcoin Cash (BCH), starting with 8 MB blocks.

SegWit activates Aug 24, 2017

Segregated Witness (SegWit), specified in BIP 141, activated at block 481,824 on August 24, 2017. It moved signature data into a separate part of the transaction. That fixed transaction malleability and let blocks hold more transactions without raising the old 1 MB base size limit.

2017 peak Dec 16, 2017

2017 was the year bitcoin went mainstream. A wave of new buyers, the ICO boom on Ethereum and nonstop media coverage pushed the price up month after month. CME and Cboe launched bitcoin futures in December, right around the top.