Percentages are often presented as evidence in public debate, but without context they can be deeply misleading.

Percentages: why “80%” often tells you almost nothing

You’ll often hear phrases like:
“80% of people support this.”
“90% satisfaction.”
“A strong majority agree.”

Instinctively, it sounds reassuring.

But a percentage on its own is usually meaningless.
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Before a percentage tells you anything useful, you need to know:

• 80% of how many people?
• Who were they?
• How were they asked?
• How many didn’t respond?

Without that context, the number is just decoration.

It’s the same trick as the old advert line:

“9 out of 10 cats prefer Whiskas.”
Nine out of ten of which cats? Compared to what?
Percentages are often used because they hide awkward details — like low response rates, small samples, or limited choices. Saying “80% agree” sounds better than saying “very few people responded.”

Percentages can be useful — but only when they come with:

• the total number,
• the response rate,
• and a clear explanation of how the figure was reached.

So whenever you hear “80%”, the right question is simple:
80% of what, exactly?