To calculate the percentage reduction (also known as percent decrease), you determine the difference between the original value and the new value, divide that difference by the original value, and then multiply by 100.
Here's a breakdown:
-
Find the Decrease (Difference): Subtract the new value from the old value.
Decrease = Old Value - New Value
-
Divide the Decrease by the Old Value: This gives you the decimal representation of the reduction.
Decimal Reduction = Decrease / Old Value
-
Multiply by 100: This converts the decimal reduction to a percentage.
Percentage Reduction = (Decimal Reduction) * 100
Therefore, the complete formula is:
Percentage Reduction = [(Old Value - New Value) / Old Value] × 100
Example:
Let's say the old value is 50 and the new value is 40.
- Decrease: 50 - 40 = 10
- Decimal Reduction: 10 / 50 = 0.2
- Percentage Reduction: 0.2 * 100 = 20%
So, the percentage reduction is 20%.
In summary, calculate the percentage reduction by finding the difference between the old and new values, dividing by the old value, and multiplying by 100.
