The Paris Region is France's leading region for economic activity, with a 2012 GDP of €624 billion (US$687 billion). In 2011, its GDP ranked second among the regions of Europe and its per-capita GDP was the 4th highest in Europe. While the Paris region's population accounted for 18.8 percent of metropolitan France in 2011, the Paris region's GDP accounted for 30 percent of metropolitan France's GDP. In 2015 it hosts the world headquarters of 29 of the 31 Fortune Global 500 companies located in France.
How many world headquarters of the 31 Fortune Global 500 companies are located in Paris?
29