It's somewhere between 10% and 15% of the volume: https://www.eia.gov/energyexplained/oil-and-petroleum-products/refining-crude-oil.php https://www.eia.gov/ener

It's somewhere between 10% and 15% of the volume: https://www.eia.gov/energyexplained/oil-and-petroleum-products/refining-crude-oil.php https://www.eia.gov/energyexplained/oil-and-petroleum-produc... It's tough to get more precise, because there are trace fuels, as well as some products like kerosene that are used as fuels and solvents.