The eurozone survived a crisis that threatened its collapse. But it held firm and challenged the world's largest economy – the American one, ending the dollar's monopoly as the global reserve currency.
However, this is only the beginning: the eurozone has barely covered half the distance to a single fiscal and budgetary union that would guarantee the stability of the single currency, and the outcome of this journey is far from predetermined.
What the single currency has given Europe, how Europeans view it, and what the future holds for the euro – journalists from BBC investigated.
1. The euro is good
That is what the vast majority of eurozone residents think. Moreover, the euro is beneficial both for the European Union (74%) and for their own country (64%), respondents said in the latest regular Eurobarometer survey in October 2018.
Only in Cyprus (47%) and Lithuania (42%) do less than half consider the euro beneficial for their country. Even in crisis-hit Greece and Italy, supporters of the single currency are in the majority – 60% and 57% respectively.
2. The world's second-largest economy
The 19 eurozone countries are home to 340 million people – more than the United States. And given that several other countries' currencies are pegged to the euro, it plays a key role in the lives of half a billion people and in the further integration of Europe.
Of the 28 EU countries, all except the UK, which is leaving the EU in March, and Denmark – though its krone is effectively pegged to the single European currency – are obliged to switch to the euro at some point.
According to the IMF, in 2018 the eurozone economy retained its second place in the world, once again overtaking China's. In terms of GDP ($13.7 trillion), it is second only to the United States ($20.5 trillion), and together they account for 40% of all global economic activity.
Before the euro, the dollar was the world's main reserve and trade currency. Now the euro accounts for about a fifth of central bank reserves and more than a third of global trade.
3. The € generation
Some still haven't gotten used to the euro. According to polls, one in seven eurozone residents converts prices into their former currency every day. And this does not depend on how long the country has been in the eurozone. For example, in Latvia, which switched to the euro only in 2014, 86% do not recall the lats, while in Belgium every second person, and in Germany every third resident, converts prices into francs and marks even after 20 years of euro circulation.
However, among young people under 24, no more than 5% do this. A whole '€ generation' has grown up in Europe. About 38% of the eurozone population have not known any other currency in their adult lives, the FT calculated.
4. Goodbye, 500 euro!
The launch of euro cash in 2002 was the largest currency exchange in history. Europeans exchanged 9 billion banknotes and 107 billion coins of former currencies for 14 billion paper and 52 billion metal euros. Since then, the volume of cash has only increased, despite the spread of payment cards, and now there are 21 billion banknotes worth €1.2 trillion in circulation.
For the twentieth anniversary, the European Central Bank completely updated the model range of the single currency. Following the 5, 10, 20 and 50 euro notes, the 100 and 200 euro notes will be replaced this year.
But the largest banknote, the 500 euro, was decided not to be carried into the future, as it turned out to be the most popular means of payment in the criminal world. Already issued 500-euro notes will remain in circulation, but from January 27, 17 national central banks will stop printing new ones, and at the end of April, the remaining two (German and Austrian) will say goodbye to the 500 euro.
The fate of the largest banknote may be shared by the smallest coins. Polls show that two-thirds of eurozone residents support the idea of getting rid of 1 and 2 euro cent coins.
5. Crisis stability
Of the 20 years of the euro era, exactly half the eurozone spent recovering from the global financial crisis a decade ago. It interrupted the steady growth of wealth in countries that adopted the single currency.
On the other hand, these two decades were marked by relatively low inflation – an average of 1.7% per year, notes the ECB, whose main task is to ensure price stability. This is lower than in individual countries in the decades preceding the switch to the euro.
And the future of the eurozone is far from cloudless. The single currency deprives eurozone countries of the ability to support competitiveness through devaluation, and therefore whenever things go badly somewhere, politicians are happy to dust off the idea of abandoning the euro.
The eurozone's growth prospects are also threatened by the European Central Bank's massive stimulus program. Since the US economy recovered faster after the crisis, the Fed turned off the printing press earlier than the ECB. Rates in America are rising, increasing the attractiveness of the dollar and the effectiveness of US monetary policy.
In Europe, rates are still near zero, and growth has yet to return to pre-crisis levels. The inevitable increase in the cost of credit will exacerbate the eurozone's main problem – servicing and refinancing giant debts is unaffordable for some countries even at current rates.
After the massive crisis a decade ago, the eurozone created protective mechanisms and, together with the European Union, raised half a trillion euros to rescue countries in trouble. However, most of this amount has already been distributed to those affected by the last crisis – Greece, Portugal, Spain, Ireland, and Cyprus.
For greater resilience, the eurozone needs closer integration: a banking union, a joint budget, a single debt market. On this path, it has taken only the first steps, and the coming 2019 promises new challenges.
US President Donald Trump continues his trade war with everyone, including Europe. Ahead of the European Parliament elections, anti-European sentiment is growing in some eurozone countries. And the main enthusiast of the banking union, French President Emmanuel Macron, is mired in domestic problems.
Meanwhile, in Germany, the largest eurozone economy and main advocate of budget discipline, the era of Angela Merkel is coming to an end. And at the ECB, the reign of Mario Draghi, whose signature appears on all new euro banknotes, is ending. In the fall, he will leave his post, and the policy of the European central bank will largely depend on who becomes its new head.