gopixa/iStock Editorial via Getty Images With China cracks down on cryptocurrency activities and lower volatility constraining the sector, trading volumes at major crypto exchanges declined by more than 40% in June, Reuters reports, citing data from London-based CryptoCompare. "Headwinds continued as China persisted with its crackdown on bitcoin mining," the firm said. "As a result of both lower prices and volatility, spot volumes decreased." Binance, which has faced increased scrutiny from regulators in the past month, keeps its rank as the biggest platform by spot trading volume, according to CryptoCompare, even as its volume fell 56% to $668B. Bitcoin (BTC-USD), which touched as high as $64.8K in April, fell to as low as $28.9K in June. In the past three months, the largest crypto by market cap fell 44%. Still, Coinbase Global (COIN) rises 0.4% in premarket trading. BTC falls 0.5% over the last 24 hours to $33.6K; ethereum (ETH-USD) falls 0.9% to $2,106; Binance Coin