How to use it
- Find new − old.
- Divide by old.
- Multiply by 100%.
See it in action
Price rises from 50 to 65: change=15; 15/50=30%.
How to verify it
30% of 50 is 15.
Common mistake
Using the new value as denominator answers a different question.
Percent Change Uses the Original
Percent change compares the difference to the starting value, not the ending value.