SOPR is measured by considering only coins moved the timescale considered (daily, hourly etc), and taking the ratio between the fiat value at the time of UTXO creation, and the fiat value when the UTXO is spent.
SOPR values greater than 1 implies that the coins moved that day are, on average, selling at a profit (price sold is greater than the price paid).
SOPR value less than 1 implies that the coins moved that day are, on average, selling at a loss (price sold is less than the price paid).
You have the ability to see the SOPR of BTC , ETH and LTC. You can also smooth the SOPR using an or of your choice.
Thank you to both TradingView and Glassnode for adding all the on-chain data