http://www.citymayors.com/statistics/richest-cities-2020.html
Chicago also has 12 Fortune GLOBAL 500 company headquarters (14 in Illinois) and Canada has 11 total. McDonald's is moving its headquarters to the West Loop (where Google just opened its midwest headquarters.) Companies from around the midwest are relocating to Downtown Chicago to take advantage of the world wide trend among educated newer workers to live in the central city.
Chicago's general population continues to shrink but with a lot of that coming in neighborhoods on the south side where families that relied on factory jobs for generations begin resettling in other parts of the country as those places have shuttered. In contrast, Downtown Chicago is experiencing a rapid rise in population and development with over 45 high rises currently under construction. That group includes three residential buildings over 850 feet (with Wanda Vista at almost '1,200.)