Tokyo is often referred to as a city, but is officially known and governed as a "metropolitan prefecture", which differs from and combines elements of a city and a prefecture. Tokyo ranked first in the Global Economic Power Index and third in the Global Cities Index. The city is considered an alpha+ world city – as listed by the GaWC's 2008 inventory and in 2014, Tokyo was ranked first in the "Best overall experience" category of Trip Ad visor's World City Survey (the city also ranked first in the following categories: "helpfulness of locals", "nightlife", "shopping", "local public transportation" and "cleanliness of streets")
Tokyo hosted the 1964 Summer Olympics, the 1979 G-7 summits, the 1986 G-7 summits, and the 1993 G-7 summits , and will host the 2019 Rugby World Cup, the 2020 Summer Olympics and the 2020 Summer Paralympics.
Tokyo has the largest metropolitan economy in the world. According to a study conducted by Price water house Coopers, the Tokyo urban area of 38 million people had a total GDP of $2 trillion in 2012 (at purchasing power parity), which topped that list. 51 of the companies listed on the Fortune Global 500 are based in Tokyo, almost twice that of the second-placed city (Paris).
Tokyo is a major international finance center. It houses the headquarters of several of the world's largest investment banks and insurance companies, and serves as a hub for Japan's transportation, publishing, electronics and broadcasting industries.