According to @Celo, a16z crypto estimates stablecoins settled about 46 trillion dollars in transaction volume last year, exceeding PayPal by more than 20x, nearing 3x Visa, and rapidly approaching ACH volumes; source: a16z crypto. a16z crypto also notes stablecoin transfers can complete in under one second at sub-cent fees, highlighting speed and cost advantages for on-chain payments; source: a16z crypto. For trading, the scale of USDT and USDC rails underpins liquidity across centralized exchanges and DeFi, where stablecoins serve as dominant quote and settlement assets that shape depth and spreads; source: Kaiko Research.