Not as many, and offset by the fact that Europe’s natural birthrate is much lower than the U.S.'s (1.2 vs 2.1).
To see the magnitude of the problem, look at this data for Europe from the U.N.:
2000 2025 2050
Median population age: 37.7 45.4 49.5
Workers per retiree: 4.6 3.0 1.9
Now look at the data for the U.S.:
2000 2025 2050
Median population age: 35.6 39.7 41.0
Workers per retiree: 5.4 3.4 2.8
In 2050, the U.S. population will be barely older than the European population is today. There will be almost one extra worker per retiree. In addition, the U.S. population is projected to grow to 400 million by then, while the European population slightly declines from today’s level.
Now, consider those numbers, and throw in the fact that the EU has much more generous retirement benefits. For example, the average retirement benefit in the U.S. is 42% of average earnings. In Germany, it’s 70%. And what’s even worse is that many of the Euro countries have large percentages of public employees, and their pension benefits are even greater.
Cite for Europe.
Cite for the U.S.
One of the big problems in Europe is that they aren’t assimilating. That’s the difference between a U.S. style melting pot and a European-style cultural mosaic. In the ‘liberal’ countries, multiculturalism is cherished, and immigrant populations are encouraged to keep their own culture (and the laws and social customs provide for that). For example, in Canada we are now allowing Sharia law to some extent.
The cultural mosaic is causing some serious problems in Europe, especially within the muslim immigrant community. They are not assimilating at all, and in fact they are beginning to cause all kinds of social upheaval. Look at what’s going on in the Netherlands, for example. In Germany there is a problem with honor killings of female muslim immigrants who attempt to marry outside their community or adopt western lifestyles. There are immigrant areas in Europe where even the police are afraid to enter. It’s a growing problem.