The islands' vivid subtropical atmosphere—brilliant sky and sea, lush vegetation, flocks of bright-feathered birds, and submarine gardens where multicolored fish swim among white, rose, yellow, and purple coral—as well as rich local color and folklore, has made the Bahamas one of the most popular resorts in the hemisphere. The islands' many casinos are an additional attraction, and tourism is by far the country's most important industry, providing 60% of the gross domestic product and employing about half of the workforce. Financial services are the nation's other economic mainstay, although many international businesses left after new government regulations on the financial sector were imposed in late 2000. Salt, rum, aragonite, and pharmaceuticals are produced, and these, along with animal products and chemicals, are the chief exports. The Bahamas also possess facilities for the transshipment of petroleum. The country's main trading partners are the United States and Spain. Since the 1960s, the transport of illegal narcotic drugs has been a problem, as has the flow of illegal refugees from other islands.