Countries are constantly competing for the most talented workers and, according to the best available immigration statistics, the U.S. has been winning.

The U.S. is home to just 4.4 percent of the world's population, but in 2010, it gained more skilled immigrants than all other countries combined.

The United States is also home to the majority of immigrant inventors, based on global patent data.

And the majority of immigrant Nobel laureates.

The figures come from new 289-page World Bank study which demonstrates the primacy of the United States as a migration destination and explains why it remains so popular.

The data-driven report does not explore recent U.S. policy changes. It takes years to compile high-quality data from every country in the world, so available figures predate the Trump administration.

Trump has repeatedly called for a merit-based immigration system. “So that you can hire people on a merit-based — you know they’re coming in — they’re people that came on merit, not based on a lottery, or not people that snuck across the border.  And they could be murderers and thieves and so much else,” Trump said in a speech at the National Space Council this week.

Highly skilled immigrants are already an integral part of the U.S. economy which, as we’ll learn later, helps ensure the country’s continued attractiveness as a destination for future immigrants.

“In the United States, immigrants make up more than a quarter of all STEM jobs in the health care, information, finance, and education industries,” write report authors Caglar Ozden, Mathis Wagner and Michael Packard. “Additionally, immigrants represent more than half of all computer scientists, software developers, and software engineers with master’s degrees and 60 percent of all STEM workers with PhDs.”

Why the American brand has been so strong

According to Gallup, 147 million potential immigrants worldwide identify the U.S. as their top destination — 3.8 times as many as choose the second most popular option, Germany.

By exploring migrants’ motivations worldwide, the study helps explain why so many choose the United States. Here, we’ll focus on the research that explains the largest relevant groups: those who come for work and those who come for education.

Economic immigrants

Immigrants from an average developing country can expect their income to multiply by a factor of four or six after moving to the U.S., the authors write. Likewise, the U.S. labor market places a higher value on skills, which makes it a particularly attractive destination for the most qualified migrants.

The U.S. has a lower tax burden than most developed countries, according to recent data from the Organization for Economic Cooperation and Development. And according to University of Chicago economist Ufuk Akcigit and his collaborators, the most desirable immigrants respond to taxation: a decrease in top tax rates leads to a disproportionately large increase in “superstar” immigrant inventors, for example.

The U.S. visa system also encourages economic immigrants through reliance on work-related visas such at the H-1B, which gives employers latitude to recruit workers with the specific skills they need in any given year. This sort of system is more flexible than the points-based systems used in Australia and Canada, the authors write, because it does not rely on government officials to determine what makes a “desirable” immigrant.

Student immigrants

In 2017 the U.S. was home to 13 of the top 15 (and 48 of the top 100) universities in the world, according to the Academic Ranking of World Universities, which was cited in the World Bank report. Not coincidentally, it’s also the top destination for international students.

Many of them — including the most qualified — plan to stay in the United States after they graduate. One study found that, in 2008, more than two-thirds of foreign-born science-and-engineering PhD students planned to stay in the U.S. after graduation. That number jumps above 90 percent among students from developing countries.

In all of these cases, the U.S. status as an immigration destination is a virtuous cycle. Successive generations of immigrants tend to follow their social networks and land in countries with large amounts of immigrants like them. Even more than the population as a whole, immigrants tend to be concentrated in large metro areas such as New York, Los Angeles, Miami, Houston, Chicago, San Jose and San Diego.

This can be even more true of high-skilled workers — research has shown that they’re more productive when they’re around workers of similar skill levels, whether it be in academia, technology or science.

The more highly skilled immigrants the United States attracts today, the more it will attract tomorrow. Barring significant federal policy changes, of course.