"Days of supply" is a good indicator as to what sort of buffer we would have in an emergency. Less "days of supply" mean we have less room to maneuver with any sort of difficulties. There would be less supply for evacuations or emergency vehicles. This is where the SPR might make a big difference for us, if we reserve its use for real emergencies, of course.

Does that confuse crude with gasoline? We can't count SPR as days of supply for gasoline unless we account for the lag time between pulling the oil out and processing it.