MEXICO CITY, Jan. 26 (Xinhua) -- Migration by Mexicans to the U.S. is at its lowest point since the 1970s, according to Mexican government and international data, despite U.S. President Donald Trump's insistence on building a border wall.

On Wednesday, Trump signed an executive order for the wall to be built, but Center for Latin American Monetary Studies (CEMLA) estimated that migration from Mexico has been slowing down since 2008 after growing from 1990 to its peak in 2007.

CEMLA reported that Mexican migration to the U.S. is now negative, with more people returning due to lower workforce demand, repatriations, border controls and a growing anti-immigrant sentiment in states such as Arizona. All these factors have jointly reduced the desire of Mexicans to go to the U.S. with many now returning to Mexico voluntarily.

Since 2012, polls have shown that only about 11 percent of Mexicans would consider migrating to the U.S., compared to 21 percent in 2007.

"We are at a stage where we could negotiate legal movement agreements...but Trump is doing the exact opposite," Gustavo Vega, an international relations expert at the College of Mexico, told Xinhua.

Of the 35 million people making up the Mexican-American diaspora, 11.6 million were born in Mexico, according to the BBVA Bancomer Foundation, with the entire group contributing around 8 percent of GDP.

A number of sectors, such as construction, manufacturing, foodstuffs, and hospitality largely depend on Mexican migrants, especially in the states of California, Texas, Nevada, Illinois, Colorado, New York, Georgia, Florida and North Carolina.

Furthermore, using official U.S. data, the Mexican government has shown that the economies of Los Angeles, Chicago and Houston, the cities with most Mexican migrants, have been growing ahead of the national average.

Meanwhile, entrepreneurs of Mexican origin own around 575,000 companies in the U.S., generating 17 billion U.S. dollars a year.

"It is a highly productive, entrepreneurial community," said Carlos Sada, former Mexican ambassador to the U.S., in November.