New York City has always been given the unique rating 1-AAAA due to its preeminent status in the national hierarchy. Chicago was originally the only other city rated 1-AAA as having influence over a large area of the country. In 1988, Los Angeles was similarly given a 1-AAA rating. Thirteen cities are given the rating 1-AA as major national business centers: Atlanta, Boston, Cleveland, Dallas, Detroit, Houston, Miami, Minneapolis, Philadelphia, Pittsburgh, St. Louis, San Francisco, and Washington, D.C.
