Center for Immigration Studies
Monthly Census Bureau Data Shows Big Increase in Foreign-Born
Immigrant population (legal and illegal) grew 1.6 million in past (fiscal) year
By Steven A. Camarota and Karen Zeigler on November 2, 2021
An analysis of the Census Bureau monthly Current Population Survey (CPS) by the Center for Immigration Studies shows that after falling for much of 2020, the foreign-born population (legal and illegal), has rebounded dramatically, increasing by 1.6 million between September 2020 and September 2021, which is the most recent data available. Unlike arrival figures for legal immigrants or border apprehension numbers, the CPS provides insight into the number of foreign-born people, also referred to as immigrants, who have actually settled in the United States, reflecting both new arrivals and those who leave or die each year. There is a lot of variation from month to month in the CPS, so any change should be interpreted in light of this variability. But the data shows clear evidence first of a decline in the total immigrant population (legal and illegal) due to Covid-19 restrictions, and then a dramatic increase reflecting the surge of illegal immigration at the southern border, the restarting of visa processing at American consulates overseas, and the return of international travelers more generally in recent months. 
Growth in the Immigrant Population. While there is some undercount, particularly of illegal immigrants, the foreign-born in Census Bureau surveys includes all persons who were not U.S. citizens at birth — naturalized citizens, lawful permanent residents, long-term temporary visitors (e.g. guestworkers and foreign students) and illegal immigrants. Growth in the total immigrant population can only be caused by new legal and illegal immigrants arriving from abroad. Births to immigrants in the United States do not add to the foreign-born as all persons born in the United States are considered native-born by definition. New immigration is offset by those immigrants who leave the country each year (previously estimated at nearly one million annually) and natural mortality among the existing immigrant population of roughly 300,000 a year. For the immigrant population to grow, new arrivals must exceed return migration and deaths.
Figure 1 shows the total immigrant population (legal and illegal) from January 2010 to September 2021, along with margins of error. Figure 1 shows that the nation’s immigrant population grew to 45.4 million in September 2021, a 1.6 million increase since September 2020. The recent growth of 1.6 million follows a 1.1 one million decline in the total immigrant population between September 2019 and September 2020. The decline almost certainly reflects the significant reduction in new legal and illegal immigration due to Covid-19 restrictions on international travel, the suspension, for a time, of visa processing at American consulates overseas, and Title 42 expulsions, which allowed the U.S. government to send illegal immigrants apprehended at the border immediately back to Mexico, even if the immigrant was not from that country. All of these factors seem to have significantly slowed the pace of new arrivals into the country. At the same time, some level of outmigration continued during this time period as did natural mortality, causing the total immigrant population to fall through the middle of 2020. Figure 2 shows a year-to-year monthly comparison in the size of the immigrant population. The biggest year-to-year monthly decline was the 1.6 million from March 2019 to March 2020. But the immigrant population fell to its smallest size of 43.8 million in August 2020…
Entire CIS.org report here.
