Currency pair euro has strengthened, or both. On the other hand, if the EUR/USD (or EURUSD) quote changes from 1.2500 to 1.2490 the euro has become relatively weaker than the dollar. The rules for formulating standard currency pair notations result from accepted priorities attributed to each currency. From its inception in 1999 and as stipulated by the European Central Bank, the euro has first precedence as a base currency. Therefore, all currency pairs involving it should use it as their base, listed first. For example, the US dollar and euro exchange rate is identified as EUR/USD. Although there is no standards-setting body
Euro national currencies had to be carried out using the process of triangulation via the euro. The "definitive" values of one euro in terms of the exchange rates at which the currency entered the euro are shown on the right. The rates were determined by the Council of the European Union, based on a recommendation from the European Commission based on the market rates on 31 December 1998. They were set so that one European Currency Unit (ECU) would equal one euro. The European Currency Unit was an accounting unit used by the EU, based on the currencies of the member