When studies rank the economic performance of U.S. cities, they’re usually really talking about broader metro areas, made up of principal cities and their surrounding suburbs and exurbs. But looking at cities themselves is useful for considering their comeback. While Nashville, Boston, and San Francisco may rank high on lists of booming metro areas, they aren’t quite as high when you look at population or job growth within city limits. In the first of a four-part series on the economic performance of American cities, CityLab’s Richard Florida examines the fastest- and slowest-growing cities. Read: The Fastest Growing Cities Aren’t What You Think