A picture is worth a thousand words:
Source: Architecture2030, based on data from the U.S. Energy Information Administration (EIA).
From Architecture2030:
According to the US Energy Information Administration, oil production from drilling offshore in the outer continental shelf wouldn’t begin until around the year 2017. Once begun, it wouldn’t reach peak production until about 2030 when it would produce only 200,000 barrels of oil per day (in yellow above). This would supply a meager 1.2% of total US annual oil consumption (just 0.6% of total US energy consumption). And, the offshore oil would be sold back to the US at the international rate, which today is $106 a barrel. So, the oil produced by offshore drilling would not only be a "drop in the bucket", it would be expensive, which translates to "no relief at the pump".
Gernot Wagner is an economist in the Climate and Air program at Environmental Defense Fund.