Downtown Winnipeg, the city's economic core, is centred on the intersection of Portage Avenue and Main Street (reputed to be one of the windiest in Canada). Downtown Winnipeg covers an area of about one square mile (2.5 km2) and is the fastest growing high-income neighbourhood in the city. More than 72,000 people work downtown, and over 40,000 students attend classes at its universities and colleges. The past few decades have seen downtown undergo major revitalization efforts; since 1999, over C$1.2 billion has been invested.