How do you calculate percentage change between 2 numbers ?

I was told it was the difference between the numbers, divided by the old number.



571 is my previous number, 596 is the new number - based on my formula, that's a 4.38% increase.



But if my "new" 596 goes back down to 571, based on my formula, that would be only a 4.15% decrease.



What am I doing wrong ?How do you calculate percentage change between 2 numbers ?
You are perfectly right in both the occassions. Please notice that the base number is differentHow do you calculate percentage change between 2 numbers ?
This is correct. The actual difference each time is 25. That stays the same.



But, the first time, you are finding 25 as a percentage of 571.



The second time you are finding 25 as a percentage of 596.



But this is the correct way to do it - you're not doing anything wrong.