Working at McDonalds as a kid gave me sensitivity to something I noticed that lasted for about another 25 years: the price of a Big Mac and the price of a gallon of gasoline were always about the same, within a few pennies, all through the '80s and the '90s; I don't know about today.
I think that the price of energy basically drives the entire economy. It's the bedrock reference point on which everything else depends.
I think Robert Heinlein spoke of a currency based on the price of energy.
I think the price of a Big Mac may exceed the price of one gallon 87 octane. Not sure, not a fan of McDonalds burgers.