The U.S. Open golf championship has been held at 50 of the nation’s elite courses since it began in 1895, including this week at Congressional Country Club in Maryland. But those courses are in only 17 states. 

This map shows the frequency, by state, using proportional symbols:

New York and Pennsylvania have hosted the most tournaments (18 and 13, respectively). Rhode Island and Georgia are at the bottom of the list, with each getting one event: 

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