According to the U.S. Department of Homeland Security (DHS) Immigration report, during 2011, there were 159 million nonimmigrant admissions to the United States according to DHS work- load estimates.
These admissions included tourists and business travelers from Canada, Mexican nationals with Border Crossing Cards, and I-94 admissions. I-94 admissions accounted for 33 percent (53.1 million) of the total admissions. The majority (87 percent) of I-94 admissions were temporary visitors for business and pleasure, while 6.4 percent were temporary workers and families and 3.4 percent were students.
The leading countries of citizenship for I-94 admissions were Mexico, the United Kingdom, and Japan.
Nonimmigrants are foreign nationals granted temporary entry into the United States. The major purposes for which nonimmigrant admission may be authorized include temporary visits for business or pleasure, academic or vocational study, temporary employment, and to act as a representative of a foreign government or international organization.
Mexican nationals traveling to the U.S. as tourists made up the majority of admissions coming from Mexico, nearly 15 million. This was followed by nearly one million visas given for temporary Mexican visitors coming to the country to conduct business.