May 23 (Reuters) - Some Mexican visitors have boycotted shops and stores in Arizona to protest the desert state's tough new law cracking down on illegal immigrants that is due to come into effect on July 29.
The following are facts about the sometimes strained trade relationship between the United States and Mexico, and the commercial and travel ties between Arizona and neighboring Sonora state in northern Mexico.
* The North American Free Trade Agreement between the United States, Canada and Mexico came into effect on Jan. 1, 1994, creating the world's largest free trade area.
* Mexico is the United States' second largest trading partner after Canada, with trade flows of around $1 billion a day.
* Under NAFTA, Washington agreed to allow Mexican trucks to haul goods on U.S. roads. But a spending bill passed by the U.S. Congress eliminated funding for a pilot program.
* In response, Mexico slapped retaliatory tariffs on $2.4 billion of U.S. products in March, and accused U.S. lawmakers of bowing to protectionist pressures from union leaders.
* Arizona has border crossings with Mexico in six towns and cities, from Yuma in the west, to Douglas in the east.
* Last year, 27.9 million people crossed legally to Arizona from Mexico, 12.8 million of them through ports of entry in Nogales, the state's largest border city.
* Goods worth $20.8 billion moved over the Arizona-Mexico border in 2008 by truck and rail.
* Mexican visitor spending in Arizona was almost $2.7 billion in 2007-2008, a figure more than double the estimated spending in 2001.
* Nearly 23,400 wage and salary jobs in Arizona are directly attributable to Mexican visitor spending.
Sources: U.S. Census Bureau; U.S. Department of Homeland Security; University of Arizona, Eller College of Management. (Reporting by Tim Gaynor; Editing by Mary Milliken and Xavier Briand)