The intense development, urbanization and suburban sprawl of New York City makes it the most populated region in New York and the collective U.S., an estimated 20 to 30 million in the eight-state Megalopolis stretching 500 miles from Boston to Washington, D.C., with New York City in the middle has 15 million residents in a 100-mile radius including Philadelphia (1.5 million in its city limits), northern New Jersey and Connecticut. A simple majority of New York's population lives within two hours of New York City. According to the July 1, 2004 Census Bureau Estimate, New York City and its six closest New York State satellite counties (Suffolk, Nassau, Westchester, Rockland, Putnam and Orange) have a combined population of 12,626,200 people, or 65.67% of the state's population.