How this calculator works
A percentage point is one unit on the 0 to 100 percentage scale. Subtract the starting percentage from the ending percentage to get the signed gap. Relative change divides that gap by the starting rate and answers a different question. Amount comparisons assume both rates apply to exactly the same total.
Formula
Point change = 100(p₂ - p₁). Relative change = (p₂ - p₁)/p₁ when p₁ ≠ 0. Amount gap = total × (p₂ - p₁).
Worked example
Moving from 20% to 25% adds 5 percentage points. Relative to the initial 20%, that is a 25% increase. On a fixed total of 200, the amount changes from 40 to 50.
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Frequently asked questions
Can the gap be negative?
Yes. Going from 60% to 50% is a change of -10 percentage points.
What if the starting rate is zero?
The point change is still defined. Relative percentage change is undefined, so that output is omitted.
Can the groups have different totals?
The rate gap can still be compared, but multiplying it by one shared total does not recover the difference in actual counts for unequal groups.