What does being in the top [blank] percent mean?


What does being in the top [blank] percent mean?

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that you’ve performed better than (100 – blank) percent of others who have done the same thing / have been surveyed.

if at school you’re in the top 10 percent of a test, it means that 9 out of 10 others got worse marks.

if you’re smoking and are in the top 5 percent risk group for lung cancer that means 19 out of 20 other people have a lower risk.


can be good, can be bad, can be meaningless if the base group is badly selected.

Imagine lining everyone up in order by whatever you are measuring.

While still in that order cut the line into 100 equally sized groups, numbered 0 to 99. Those are percentile groups 0 is the lowest bucket for that measure, 99 is the highest. The others are in between those two.

Take all of the examples of things you are measuring and line them up in order from best to worst, best on top.

Slice off the top [blank] percent of them and put them in a bucket.

If something is in the “top [blank] percent”, it would now be in the bucket.

Another way to think about it: if you are in the top X%, then it means (100 – X)% of everyone else is worse than you. E.g. if you’re in the top 5%, then (100 – 5)% = 95% of people are worse than you.

“Bottom %” is the same concept but it describes the worst instead of the best.