World events have a direct effect on the price of oil: OPEC, wars, political, and religious unrest. The key to a rational oil market price (if there is such a term) is a balance of reserves, inflation, political prudence, and demand. Extremely high or extremely low prices are beneficial to no one.

As this chart indicates, when world events are awry or the domestic environment is skewed, oil prices increase or decrease to the extreme creating a negative situation for both producers and consumers.

For the 21st century, the optimum petroleum price level (the point at which producers can profitably produce and consumers can willingly afford) ranges between $70 and $75 per barrel.