The records are ordered by the date of entry into the union. The first three lines of the file are:
Delaware, DE, 12/7/1787, 1954, 941875
Pennsylvania, PA, 12/12/1787, 44817, 12856989
New Jersey, NJ, 12/18/1787, 7417, 8969545
U.S. States. Create a class State with five properties to hold the information about a single state and a method that calculates the density (poeple per square mile) of the state.