The numbers of undocumented vary according to the methodology used, and there’s also a lag in the estimates because it takes time for accurate data to become available. The last estimate released by the Office of Immigration Statistics at DHS came in December 2018: As of January 1, 2015, there were 11.96 million undocumented immigrants in the U.S. The most recent Pew Research estimate puts the total number of unauthorized immigrants at 10.5 million in 2017. Overall, this represents a minority of the foreign-born population, which in 2017 numbered
44.5 million—45% of whom are
naturalized citizens, and 27% of whom are lawful permanent residents.
While anti-immigrant groups maintain that the flow of illegal immigrants has increased, estimates show that over a longer period the number of undocumented immigrants has declined, from 12.2 million in 2005 to 10.5 million in 2017
according to Pew’s estimates. DHS figures don’t go beyond 2015, but they
estimate that the population of undocumented immigrants increased by 70,000 people per year between 2010 and 2015, compared to increases of 470,000 per year between 2000 and 2007.