Philadelphia is the center of economic activity in both Pennsylvania and the four-state Delaware Valley metropolitan region of the United States. Philadelphia’s close geographical and transportation connections to other large metropolitan economies along the Eastern Seaboard of the United States have been cited as offering a significant competitive advantage for business creation and entrepreneurship. Five Fortune 500 companies are headquartered in the city. As of 2021, the Philadelphia metropolitan area was estimated to produce a gross metropolitan product (GMP) of US$479 billion, an increase from the $445 billion calculated by the Bureau of Economic Analysis for 2017, representing the ninth largest U.S. metropolitan economy. Philadelphia was rated by the GaWC as a 'Beta' city in its 2016