The Department of Homeland Security reported that there were 179 million non-immigrant admissions to the U.S. in 2004. The vast majority of these admissions — 148 million — were for Mexicans and Canadians who have border crossing cards that permit entry into the U.S. for short stays, including daily commutes for work. Read More
Border Crossing Cards
Russell Heimlich is a former web developer at Pew Research Center.