Ether (ETH) spot exchange-traded funds (ETFs) are expected to attract $15 billion of net inflows in the first 18 months after their anticipated approval for trading in the U.S., according to Bitwise CIO Matt Hougan. The potential inflows can be estimated by comparing the relative market caps of bitcoin (BTC) and ether, with investors likely allocating funds to ETFs proportionally. Bitcoin’s first-mover advantage may reduce the inflows into spot ether ETFs. In the U.S., investors have already invested $56 billion in spot bitcoin ETFs, a figure projected to grow significantly by the end of 2025.