The day office in Downtown City National Plaza offers spectacular 36th-floor views of the Los Angeles central business district. Encompassing an entire city block, City National Plaza is a day office building that has dominated the downtown skyline for more than 30 years with its two 51-story day office towers. Tenants include City National Bank and international law firm Paul Hastings. 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. Although many are no longer headquartered here, plenty of financial institutions have regional bases in the city. Los Angeles is also the largest manufacturing center in the western US and the ports of Los Angeles and Long Beach together comprise the fifth busiest port in the world. The city is home to too many companies to mention, but it's the University of Southern California (USC) that is its largest private sector employer.