I believe that this is the third year in a row that I've had to explain this....
Because of the EPA and state regulatory agencies, there are no less than SEVENTY-TWO different blends of gasoline that vary between Summer and Winter, regions, regions by altitude, states by insane environmental laws, etc.
Unfortunately, changing from Winter to Summer blends while factoring in greatly increased driving on the Northern tier and somewhat increased driving in the Southern tier means that refineries have to shut down to reconfigure, then reallocate output by region.
This invariably causes regional shortages. (By law, oil companies cannot coordinate among themselves to synchronize their refinery shutdown schedules.)
Every Spring and every Fall the prices get volatile, then settle down and roll back when the seasonal blends are in place.
Obama can't do anything about it, the oil companies can't do anything about it. We have allowed our unfettered government bureaucracy to force this down our throat twice a year.
Just say a quick prayer that Iran doesn't take any more crazy pills during this time of volatility.
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