Question Marks over the Dominance of the USD

For 100 years, the American dollar has been the world's dominant financing currency, recently challenged by the Euro. In the last 10 years, the dollar has fallen to 60% of FX reserves held globally with Euros at 25%, 15% in other currencies. If the renminbi becomes fully convertible and dispenses capital controls it would become the world's third global currency. Capital controls limit the flow of money into and out of a country. China allows inflow in the context of FDI (i.e. long-term investors) whereas it restricts the purchase of Chinese financial assets. Restricting purchase of currency to restrict purchase of financial assets, restricts the appreciation of the currency. Capital controls can be seen as an alternative to quantitative easing and intervention.