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Camilla, I agree completely with Steve's comments. There is a great deal sloppiness in the language we use when talking about percentages. Whenever you see or hear the word percentage you should ask "Percentage of what?" In your question I would feel more confident about Steve's "least incorrect answer" if you had asked for percentage change rather than percentage difference. Percentage change indicates that the quantity is changing over time and you want the change as a percentage of the earlier value as is Steve's interpretation. Percentage difference does not indicate any order and I have no idea if you want the difference as a percentage of the smaller value or as a percentage of the larger value. Harley  


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