In the old EU-15, the rate of population growth has been slowing down and is now close to zero; immigration is the unique factor that has had a dampening effect on this slackening process (in many cases, it prevents straightforward depopulation.
Between the mid-1960s and the mid-1990s, the natural increase fell by more than two million, from 2.56 million in 1965 to 0.33 million in 1995. As the number of deaths was approximatively constant, this phenomenon essentially can be attributed to a substantial drop in the number of births, which declined by more than one-third in only three decades (from 6.1 million in 1965 to 4.0 million in 1995). Despite the fact that in 2000 the EU has 100 million more inhabitants than the United States (370 million versus 270 million), the number of births in the mid 1990s was similar (3.915 million in the United States in 1996). During the last few years, for the first time in the history of the European community, the contribution of immigration to population growth has becopme stronger (indeed, much stronger) than the impact of natural increase (which, in turn, is stimulated by past immigration), as the table below indicates. The lesson is clear: the EU is entering a new historical stage, the age of migratory dependency.
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