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Open calculator →Percent Change Calculator
Use your own numbers after reviewing the example below.
Quick answer
Subtract the new value from the original value, divide the decrease by the original value, and multiply by 100.
Formula or method
Percentage decrease = (old − new) ÷ old × 100%
Step-by-step
- Find the decrease: old value − new value.
- Divide the decrease by the original value.
- Multiply by 100 to express the result as a percent.
Worked example
A price falls from $80 to $68. The decrease is $12. 12 ÷ 80 × 100 = 15% decrease.
How to interpret the result
Always divide by the original value for a standard percent-change calculation. Using the new value changes the denominator and produces a different percentage.
Common mistakes
- Dividing by the new value.
- Dropping the ×100 step.
- Confusing a 15 percentage-point drop with a 15% decrease.
Frequently asked questions
What is the percentage decrease from 100 to 80?
20%.
What is the decrease from 80 to 68?
15%.
Can percent decrease exceed 100%?
Not when both old and new values are nonnegative and the new value is zero or greater; a fall to zero is a 100% decrease.