# What is mathematical basis for the percent symbol (%)?

Percent means 1 part of 100 or 1/100 and is indicated with %. Per mille means 1 part of 1000 or 1/1000 and is indicated with ‰, so it seems that these symbols indicate the mathematical operations that they perform (i.e., the divisor in per mille is 10X greater. However I can't seem to reconcile how % suggests 1/100 and ‰ suggests 1/1000.

Is this just convention or is there a deeper meaning?

Thank you.

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Have you seen this? – J. M. Sep 5 '11 at 17:53
% has two 0s and a slanted 1 in it, and likewise for ‰... :) – Rahul Sep 5 '11 at 21:23
@Rahul: you made up the "slanted 1", right? That's why you put the :) joke sign at the end? – GEdgar Sep 5 '11 at 22:05
@GEdgar, as far as I know, I made up everything in that comment. – Rahul Sep 5 '11 at 23:58
@Rahul: It's a good mnemonic nonetheless... – Assad Ebrahim Jun 30 '14 at 3:31

## 1 Answer

It's a convention that started sort of as a fluke. In a 14th century Italian manuscript, a sideways letter P is written to stand for 'per 100' or 'per cento'. It then slowly evolved. A more in depth bit can be found under the percent sign history here, and on the wiki page.

In addition to percent 0/0, and permil 0/00, there is also permyriad 0/000 for 1/10000.

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I can't find it; is there a permyriad symbol in Unicode or $\TeX$? :) – J. M. Sep 6 '11 at 1:37
Unicode U+2031 ‱, as referenced here – process91 Oct 10 '11 at 6:25