New research, published on July 22 2015 by the University of New Hampshire Casey School of Public Policy, shows that the number of Mexicans entering the United States, legally or otherwise, has decreased sharply in recent years.
Researchers at the Univeristy of Texas and the University of New Hampshire say that the number of Mexican immigrants entering the US hit a peak in 2003. Since then, numbers have declined by more than half.
Lead author of the published research, Rogelio Saenz, said that immigration to the US from Mexico is declining due to increased US border security, and due to the rising numbers of detentions and deportations of unauthorized immigrants. He added that the growth of Mexico's economy and a decline in the country's birth rate were also factors.
57 per cent decline
Between 2008 and 2012, 819,000 people entered the US from Mexico. In contrast, 1.9 million migrated from 2003 to 2007, representing a decline of 57 per cent according to figures from a US Census. These figures do not distinguish between legal and illegal US immigration.
Saenz, dean of the College of Public Policy at the Univeristy of Texas San Antonio [UTSA], said: "In the 1960s and 1970s it was not uncommon for the average Mexican woman to have seven births. As a result, the population of Mexico was quite youthful and 30 years ago approximately 35 per cent of the Mexican population were below the age of 15."
The previous high birth rate meant that many young Mexicans were unable to find employment at home. However, birth rate numbers in Mexico are not the same as they were three decades ago; the country's birth rate is now similar to that of the US.
Saenz said: "The excess labour force that existed in Mexico just 30 years ago is no longer there. Today we're seeing wealthier Mexican immigrants more likely to enter the United States on special visa programs. These programs often require them to make employment-creating investments."
Fleeing crime and violence
Rather than seeking immigration to the US to find employment in the construction sector as was previously the case, Mexicans are now arriving in the United States fleeing crime and violence in Mexico, mainly due to drug wars between rival cartels and gangs.
'Those arriving are much more likely to be naturalized US citizens coming back, English-speaking, better educated, older and female, compared with those Mexican immigrants arriving in the US decades ago', said Saenz.
Unauthorised Mexican immigrants
A similar study conducted by the Pew Research Center, shows that illegal Mexican immigrant numbers in the US has dropped since 2007. In 2007, 6.9 million unauthorised Mexican immigrants were living in the United States.
In addition due to economic factors and changing migration patterns, by 2010 the net migration figure had likely reached zero according to the Pew Research Center study. Pew added that since 2010, more Mexicans have departed the US than arrived. Therefore since 2010 more Mexicans have left the US than have arrived in the US.
The Pew Center's research seemingly disproves recent comments made by prospective Republican presidential candidate, Donald Trump, who said that unauthorised Mexican immigrants are 'flowing in like water' across US borders.
However, despite numbers dropping since 2007, in some US states Mexicans make up around 89 per cent of the total illegal immigrant population, with California having the largest concentration of illegal immigrants from Mexico with 1.6 million.