Argentina's economy is one of the richest and most diversified in Latin America. Argentina benefits from rich natural resources, a highly literate population, an export-oriented agricultural sector, and a diversified industrial base. The Pampas is the nation's chief agricultural area; however, since the 1930s there has been a great rise in production in other areas also. Livestock (cattle and sheep) and grains have long been the mainstay of its wealth; its cattle herds are among the worlds finest. Food processing (in particular meatpacking, flour milling, and canning) is the chief manufacturing industry; motor vehicles, textiles, chemicals, petrochemicals, and steel are also major products. Argentina's principal imports are machinery, motor vehicles, chemicals, metals, plastics, and other manufactured goods. The chief trading partners are Brazil, the United States, China, and Chile.