Despite reaching replacement level fertility in the 70s, the population has continued to explode, and this is due entirely to immigration. This is historically

Despite reaching replacement level fertility in the 70s, the population has continued to explode, and this is due entirely to immigration. This is historically unprecedented. http://www.numbersusa.com/content/learn/sustainability/biggest-population-boom-ever.html http://www.numbersusa.com/content/learn/sustainability/bigge...