In golf there is something called a perfect round. A perfect round is where all 18 holes were played on average at one under par(average of birdie on every hole) resulting in a score of 55 on a par 73 course, 54 on a par 72, 53 on a par 71 and a 52 on a par 70 course. The term perfect round is used for a 54 as the lowest score generally accepted as being in the realm of possibility among professional golfers on a par 72 course. This has remained the standard and has never been achieved by a professional golfer in a professional event.
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