And half of them are undocumented. This I derived from 2000 year estimates of 18-24 year old non-citizens by Jeff Passell, now of at the Pew Hispanic Center. Passell estimated that there were 2.9 million non-citizens in this age range. These young adults were 16% of the 18.5 million non-citizen population – a markedly higher rate than for the entire population – 9.6% were in this age group in 2000. Passel estimated that 51.3% were undocumented; 35.4% had green card (legal permanent status), 5.3% were refugees, and 7.4% were non immigrants (temporary workers, students, etc. There are about 600,000 foreign students in America. It just seems more). Bottom line: we are depending on foreign workers for one tenth of our new entrants into the workforce.