What percentage of Natural gas does the Us use?

I assume you are asking about oil and how much total oil we have left in the world.

In the United States we have roughly 400 years or so (at current use rates) of oil reserves that we currently know about. Most of that is on the Green river formation which takes up all of Colorado, Wyoming and Utah. Some estimate that this is roughly 4 trillion barrels alone, others claim about 2 trillion.

The Dakotas also have a large shale oil reserve. These combine to dwarf all of the Middle East's reserves.

Thankfully environmentalist's have made this impossible to obtain.