Coinbase Global Inc (NASDAQ:COIN), the U.S.-based cryptocurrency exchange, reported that its trading volume doubled in the fourth quarter compared to the third quarter, totaling $154 billion. What Happened: During an earnings call on Thursday, Armstrong said ETFs were a “win-win for Coinbase.” The Coinbase CEO added, “So in preparation for this launch, we won eight of 11 Spot Bitcoin (CRYPTO: BTC) custody mandates from issuers. And today, Coinbase custody is about 90% of the 36 billion in Bitcoin ETF assets as a result. So across the entire industry, we’ve seen over $4 billion of net inflows i…