According to TokenInsight's "Bottom Public Chain 2019 Q2 Research Report", in the second quarter of 2019, the market value of the underlying public chain in the industry accounted for 14.9%, a slight decrease from the previous quarter; the main reason can be attributed to the market inflows leading to a large influx of funds Due to Bitcoin, Bitcoin's market share reached 61.7%. In the second quarter of 2019, except for Tezos, the return on investment for each project was positive, and the underlying public chain continued its growth momentum in the first quarter. Among the top ten projects in the market capitalization, Ethereum and Qtum have the highest return on investment; Ethereum and Ontology have the smallest retracement. In the head project, Ethereum, EOS and Tron are still ranked in the top three market capitalization and trading volume, of which Ethereum is dominated by 69%; the recent technological breakthroughs in the public chain focus on cross-chain, fragmentation and privacy computing. The security of the blockchain remained severe in the second quarter, with economic losses resulting from security incidents from the beginning of 2019 to the end of the second quarter of $731 million.