I think the currency dollar should be changed and should not be used as the standard currency. Because the world financial system need to use gold. The assets with limited help guarantee the banknote. If printing is available out it must be the only gold as a reserve of 100%. President Richard Nixon U.S. announced cancel use the gold. Canceled that the United States was the only nation can print banknotes out a quantity a lot of according to need. The deflation is almost never appearing economic system in America again. And the dollar is the main currency of the world. Make things too expensive worldwide