Andorra and the euro facto" used the EU's euro (the currency of the Eurozone states) as it had historically used the French franc and Spanish peseta. When those two currencies were replaced by the euro in 2002, the euro replaced the franc and peseta as the sole circulating currency in Andorra. Unlike the three other European microstates outside of the EU, Monaco, San Marino and the Vatican City, which adopted the euro when it was introduced, Andorra did not conclude a monetary agreement with the EU but rather used it unilaterally. These agreements gave the three microstates the right to issue their own euro
Reserve currency It was "absolutely conceivable that the euro will replace the US dollar as reserve currency, or will be traded as an equally important reserve currency." Econometric analysis by Jeffrey Frankel and Menzie Chinn in 2006 suggested that the euro could replace the U.S. dollar as the major reserve currency by 2020 if either the remaining EU members, including the UK and Denmark, adopted the euro by 2020, or the recent depreciation trend of the dollar persisted into the future. In recent years, the euro's share of the worldwide currency reserve basket has continued to increase—albeit at a slower rate than