Less than half of the total number of undocumented immigrants already in the U.S. are from Mexico for the first time in more than 50 years, according to a new analysis.
New Pew Research Center estimates based on government data conclude that out of 10.5 million undocumented immigrants in the country in 2017, 4.9 million originally came from Mexico.
The number of undocumented Mexican immigrants in the country declined largely because more left the country than arrived, though the group remains a strong plurality among those coming to the U.S. without authorization from other Latin American countries.
The fall in percentage marks the first time Mexicans made up less than half of the total undocumented population since the 1960s, when an immigration overhaul that restricted entry from Western Hemisphere countries led to a steady rise in Mexican migrants illegally coming into the U.S.
The number of undocumented immigrants from Mexico was lower in 2017 than at any point since 2001 and 2 million short of its peak of 6.9 million in 2007. The number of apprehensions of Mexican migrants has also fallen behind those of non-Mexicans for the past three fiscal years, according to Pew.
Despite the drop in undocumented Mexican immigrants, the U.S. is seeing a rise in the number of unauthorized migrants from other countries.
There were 5.5 million non-Mexican undocumented immigrants in 2017, slightly higher than the 5.3 million that were in the country in 2007. A large share of that increase comes from Asia and Central America, particularly El Salvador, Guatemala, Honduras and India, according to Pew.
The overall undocumented population remained statistically the same between 2016 and 2017, marking its lowest size in both years since 2004.
Pew notes that the fall in the share of undocumented migrants from Mexico follows the trend that a growing number of immigrants in the country without authorization overstay visas rather than illegally cross the border.