The number of U.S. residents born abroad has fallen by more than 2 million since President Donald Trump began his second term, with roughly 72%, about 1.6 million, of those who left estimated to have been living in the country illegally.

The decline, described as "unprecedented," was reported by the Center for Immigration Studies (CIS) after analyzing the federal Bureau of Labor Statistics’ Current Population Survey.

CIS attributed the drop largely to increased out-migration in response to intensified immigration enforcement, though it cautioned that its analysis carries certain caveats. Some data from the BLS may be incomplete or inaccurate, but cross-referencing suggests the overall numbers are reasonably reliable.

The organization noted that some undocumented immigrants may have avoided responding to the survey, but this aligns with a reported 10% decrease in non-citizens from Latin America who arrived in the U.S. after 1980, a demographic closely linked to the undocumented population.

The survey also showed significant job growth among U.S.-born residents, which CIS said is partly due to foreign-born workers leaving their positions over the past six months.

CIS described the decline as a dramatic reversal from previous trends of steady population growth, concluding that "something has fundamentally changed" in the U.S. immigration landscape.