Essendon ended the 2011 home and away season on exactly the same points for as points against, 2,217, giving them a percentage of exactly 100! And what is the magic formula that the AFL and most leagues use to determine “percentage?” It’s simply the points FOR divided by the points AGAINST, then multiplied by 100!
eg. Richmond Points for 112 Points against 84
112 / 84 = 1.333 1.333 x 100 = 133.33 %
Interestingly, the SANFL uses a different percentage system, where 100% is the pinnacle. The formula?
100 x For / (For + Against)
eg. Glenelg (keep it in the Tiger family) FOR-112 AGAINST 84
100 x 112 / (196) =57.14%
I personally like this system because if the aggregate score between the two teams is 196, then Glenelg’s score of 112 represents 57.14% of the total score. Click here for some further reading on www.sanfl.info
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The only issue I have with the current AFL system is that it rewards lower scoring teams. Eg. if a team wins by 55 to 40 they will have a percentage of 137.5. On the other hand a higher scoring team winning by the same margin, eg 100 to 85, will only have a percentage of 117.64.
I remember a few years back the dogs had a much higher ‘points difference’ than the Swans, But the dour and low scoring nature of the Swans allowed them to have a higher percentage. Eg. Dogs 1000 points for 850 against (%117.64), Swans 650 points for 550 against (%118.18). Effectively in this example the Dogs point difference is 50 higher, but leads to a smaller percentage.
That can’t be right???
Great points there Garfdog…the AFL always appears to market the game as a high-scoring and exciting, even to the extent of CEO Andrew Demetriou condemning Sydney as the ugly ducklings, albeit they were premiers that year. As you’ve clearly pointed out however, teams are better off to play a dour defensive game. A conundrum of sorts!
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