What it means
The difference between two percentages.
Examples on this page are illustrations, not findings from the research cards.
Worked example
A rise from 40% to 50% is 10 percentage points. Relative to the starting value, that is a 25% increase.
Hypothetical example: a completion rate rises from 40% to 50%. The difference is 50 − 40 = 10 percentage points. If each rate described 100 people, it would correspond to 40 completing at the first rate and 50 at the second.
Compared with the starting rate, the increase is 10 ÷ 40 × 100 = 25%. A 10% relative increase from 40% would instead reach 44%, because 40 × 1.10 = 44. The words after the number change what the number means.
A closer look
Percentage points describe the gap between two percentages. Subtract the starting percentage from the later percentage to find the change in points. This is useful for comparing rates, such as the share of people who complete a course. The calculation keeps the percentages on their original scale, so the result is expressed in percentage points.
A relative percentage change answers a different question: how large is that gap compared with the starting rate? Divide the gap by the starting percentage and multiply by 100. The same change can therefore have two different numerical descriptions. When reading a finding, check which one the researcher reports. A percentage-point change is not automatically the programme's effect; that also depends on the study design. Relative percentage change is undefined when the starting percentage is 0%, because the calculation would divide by zero. You can still report the percentage-point difference.
A common misunderstanding
A 10-percentage-point increase from 40% reaches 50%; a 10% relative increase reaches 44%.
Check the explanation
Sources
The wording and examples are original explanations informed by these references.
Cite this explanation
Percentage points. aikyam school. https://aikyam.school/glossary/percentage-points/
Used in these cards
221 cards use this term
The original research wording is preserved in these cards.
