How is percentage change calculated?

((new − old) / old) × 100. Positive means increase, negative means decrease.

Percentage change is undefined when the old value is 0; the tool will show an error.

Can I use it for price changes?

Yes. Old = original price, new = current price.

Calculate percent change from old to new: ((new − old) / old) × 100. Positive = increase, negative = decrease.

Old value

New value

How is percentage change calculated?: ((new − old) / old) × 100. Positive means increase, negative means decrease.
What if old is zero?: Percentage change is undefined when the old value is 0; the tool will show an error.
Can I use it for price changes?: Yes. Old = original price, new = current price.

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