When comparing two percentages, it's easy to mix up an absolute change (in percentage points) with a relative change (in percent). They can tell very different stories about the same numbers.

Example
The XYZ party scored 20% in the previous election, and got 30% of the vote in today's election.
Saying "the XYZ party got 10% more votes than in the previous election" is incorrect! A 10% increase on 20% would only result in 22% of the vote (20 × 1.10 = 22).

The absolute change: percentage points

30 - 20 = 10
In today's election, the XYZ party got 10 percentage points more of the vote than in the previous election. This is simply the difference between the two percentages.

The relative change: percent

Initial value V: 20 (initial percentage)
Percentage value P: 10 (absolute variation)
p = P / V = 10 / 20 = 0.5
In today's election, the XYZ party received 50% more votes than in the previous election. This is the percentage change between the two values.

So: the party gained 10 percentage points, which corresponds to a 50% increase relative to its previous score. Both statements are correct — they just answer different questions.

You can find more background on this topic on Wikipedia.

Ready to calculate your own numbers? Go back to the percentage change calculator.