Three of the most common percentage calculations, all in one place.
Use "X% of Y" — enter the discount percentage as X and the original price as Y to find the discount amount.
Use "X is what % of Y" — for example, entering 30 and 150 tells you 30 is 20% of 150.
Percentage change is always measured relative to the starting point, since that's what defines the size of the change — dividing by the new value instead would give a different, incorrect result.
Yes — the "% change from X to Y" mode handles both increases and decreases automatically, labeling the result accordingly.