Why is it still a buck more than gasoline?
You ask an interesting question re ULSD vs E10 gas.
I’ve not seen this proportionality in my lifetime.
LSD.....................Low Sulfur Diesel not the psychotic drug...............or maybe both.....................
“Why is it [diesel] still a buck more than gasoline?”
Different costs of production. Different supply. Different demand. In some locals, different taxes. Plus, localized production, so the dip in raw materials (crude) does not necessarily increase the supply in another.
Might as well ask why the price of gallon of milk is different than a gallon of orange juice.
Sure, they might have some similar underlying costs, but not as much as you think.