Determining the future price on oil can be very complicated and is based on more than supply and demand. The announcements by OPEC are only part of the equation to figure future oil prices. U. S. production, oil storage capacity, reservoir pressure, and local energy needs all have an impact on the future price. Reservoir pressure is a key factor, because underground pressure in large reservoirs can be lost if production is not managed. Countries such as Saudi Arabia also need to keep up oil production in order to produce the associated gas that they need.