The economy of Los Angeles is driven by international trade, entertainment (television, motion pictures, video games, recorded music), aerospace, technology, petroleum, fashion, apparel, and tourism. Los Angeles is also the largest manufacturing center in the western United States. The contiguous ports of Los Angeles and Long Beach together comprise the fifth-busiest port in the world and the most significant port in the Western Hemisphere and is vital to trade within the Pacific Rim. Other significant industries include media production, finance, telecommunications, law, healthcare, and transportation. The Los Angeles-Long Beach-Riverside combined statistical area (CSA) has a gross metropolitan product (GMP) of $831 billion (as of 2008), making it the third largest economic center in the world, after the Greater Tokyo Area and the New York-Newark-Bridgeport CSA. If counted as a country, the surrounding CSA has the 15th largest economy in the world in terms of nominal GDP. Los Angeles has been classified an "Alpha(-) world city" according to a 2008 study by a research group at Loughborough University in England.
Until the mid-1990s, Los Angeles was home to many major financial institutions in the western United States. Mergers meant reporting to headquarters in other cities. For instance, First Interstate Bancorp merged with Wells Fargo in 1996, Great Western Bank merged with Washington Mutual in 1998, and Security Pacific Bank merged with Bank of America in 1992. Los Angeles was also home to the Pacific Exchange, until it closed in 2001.
The city is home to seven Fortune 500 companies. They are aerospace contractor Northrop Grumman, energy company Occidental Petroleum, healthcare provider Health Net, metals distributor Reliance Steel & Aluminum, engineering firm AECOM, real estate group CB Richard Ellis and builder Tutor Perini.
The metropolitan area contains the headquarters of companies who moved outside of the city to escape its taxes but keep the benefits of proximity. For example, Los Angeles charges a gross receipts tax based on a percentage of business revenue, while many neighboring cities charge only small flat fees.
The University of Southern California (USC) is the city's largest private sector employer and contributes $4 billion annually to the local economy.
In January 2010 many of the aerospace firms with operations in Los Angeles County are relatively small compared to the larger corporations. The United States Postal Service operates post offices in Los Angeles, the main one of which is located at 7001 South Central Avenue.
According to the city's 2009 Comprehensive Annual Financial Report, the top ten employers in the city are the City of Los Angeles, the County of Los Angeles, University of California, Los Angeles, University of Southern California, Cedars-Sinai Medical Center, Kaiser Permanente, Fox Entertainment Group, Farmers Insurance Group, TeamOne and Northrop Grumman.