Excellent comment, but do not see too far and I apologize to the Americans if my message is offensive. The United States of North America is the only country that buys the natural recuse of any part of the world with paper money that they produce and that is worth 100 thousand times less, simply and simply because they used to the world that the dollar has to be the main currency globally. the expense generated by a barrel of oil is not the same as that generated by the printing of a dollar.