This graph shows the rate of the population in the USA which have their birthplace in a foreign country from the beginning of the 20th century to 1998.
until 1910 there was an increase of the foreigners. If you look at the graph closely
you can see that it climbs up to 15%, but from then on the population decreases nearly constantly until 1970. Then it recovers and it rises up to 9% in 1998.