When topped-off in August 1983, it was the tallest building south of New York City and east of the Mississippi River, taking away the same title from the Westin Peachtree Plaza Hotel, in Atlanta, Georgia.[5] It remained the tallest building in the southeastern U.S. until 1987, when it was surpassed by One Atlantic Center in Atlanta, and the tallest in Florida until October 1, 2003, when it was surpassed by the Four Seasons Hotel and Tower, also in Miami. It remains the tallest office tower in Florida and the second tallest building in Miami.
http://en.wikipedia.org/wiki/Southeast_Financial_Center