The Net Unrealized Profit/Loss (NUPL) metric compares BTC and ETH performance by showing investor profitability relative to the average on-chain cost basis.

A NUPL >0.5 indicates that unrealized profits exceed 50% of the asset's market cap, marking new ATHs and the euphoria phase.

During the market rally from spot Bitcoin ETF approvals, BTC's NUPL crossed 0.5 and entered euphoria three months before ETH's, as BTC holders' profits grew faster.