Why the 10-year view is red
Over a decade, difficulty has grown far more than price. That is the honest read, and it does not mean mining lost money. Machines are several times more efficient per terahash than they were in 2016, so a miner today buys far more hashrate per dollar and burns far less power per hash. This chart holds hardware constant. For revenue per unit of hashrate, use the hashprice chart.
Window vs. rolling spread
The window view answers one question: over the dates you picked, did price or difficulty move more? The rolling view asks that same question on every date, each time looking back a fixed number of days, so you can see the stretches where miners had a tailwind or a headwind inside a longer trend.
Daily price and network difficulty are aligned by UTC date and sourced from the Blockchain.com Charts API. Difficulty is carried forward between its adjustments, which happen about every two weeks. Data observed through n/a.
This chart is educational and does not estimate any specific miner's profitability or constitute investment advice.