Diesel is more know because it has to be low sulphur. When that changed the price did also.
12 years ago I was just graduating college and got some money for graduation. A very smart man told me the world has a insatiable appetite for fossil fuels. Until something better is found. He told me to invest in fuel stocks and everything to do with it.
When prices are down I win at the pump....When prices are up I win in the market.