← A Number's True Size · Lesson 1 of 4
Per cent and percentage points
When a rate goes from 4% to 6%, two different things are true. It rose by 2 percentage points: 6 minus 4. And it rose by 50%: the 2 points are half of the 4 it started at.
Both are honest, but they sound very different. A headline that wants a change to sound big tends to use the per cent; one that wants it to sound small uses the points.
When you see a change in a rate, ask for both, and ask what it started at.
An interest rate goes from 4% to 6%. Which statement is correct?
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