Quandaries and Queries


When calculating a percentage, if the formula is
A(new) - B(old)/A(new)
Is this percentage change or percentage increase?




Hi Betty,

Percentage change, percentage increase, percentage markup, percentage decrease, percentage reduction; all of these terms are used ambiguously at times. In many situations there is a time order as you indicate in your question with the words old and new. In this situation I think most people would say the percentage change is

 (new - old)/old 100

that is you look at the change relative to where you started. If this is a positive number I would call it percentage increase, and if it is negative I would call it percentage decrease.

I don't know of a term for

 (new - old)/new 100



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