As the GOP presidential nominee, Donald Trump surfs a wave of anger over illegal immigration.
"People are pouring across the southern border," he asserts repeatedly.
A report released Tuesday says otherwise: The population of Mexicans living illegally in the United States decreased 1.1 million from its peak in 2007 to 5.8 million in 2014, and the number of undocumented immigrants overall _ 11.1 million _ hit its lowest point since 2010.
Based on a Pew Research Center analysis of census and other government data, the report finds that illegal immigration in general "has stabilized since the end of the Great Recession." That's because, while more Mexicans have left the United States than arrived here, the influx from other regions, including Asia, Central America and sub-Saharan Africa, has grown.
Mexicans living illegally in the U.S., many of whom have been here for decades, still make up slightly more than half, or 52 percent, of America's total undocumented population. But that could change.
As net migration from Mexico declined, the report notes, "immigration from Asia did not flag. ... As a result, among all newly arriving immigrants in the U.S., more now come from Asia than from Latin America, a change since 2008."
The Pew Research Center, based in Washington, studies demographic trends and describes itself as a nonpartisan "fact tank."
The report found that most of the 50 states saw "no statistically significant" change in their undocumented populations. In seven states, however, the number living there illegally dropped. In six it increased.
That growth appears to have been driven by countries other than Mexico _ and by immigrants who arrived with legal status but then overstayed their visas, the report states.
Nationwide, for example, the number of unauthorized immigrants born in India, most of whom would have entered the U.S. legally, grew from 370,000 in 2009 to half a million in 2014.
Because no hard numbers exist for the number of undocumented immigrants in the U.S., Pew's researchers analyzed a combination of census surveys and other data to estimate the changes in the population.
Princeton University sociologist Douglas Massey, who was not involved in the Pew report, said its findings are consistent with his own and other research.
He cited another reason that undocumented immigration from Mexico is flat or negative: Mexican fertility rates have fallen drastically since 1970.
"Mexico has become an aging society with a decelerating rate of labor force growth. Migration is generally initiated between the ages of 18 and 30," he said. Mexico's average age now is 28.
"If people don't migrate between these ages, they don't migrate at all," Massey said. "So I think mass Mexican migration is over and won't be coming back."
