- Per mil
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A per mil or per mille (also spelled permil, permille,[1] per mill or promille) (Latin, literally meaning 'for (every) thousand') is a tenth of a percent or one part per thousand. It is written with the sign ‰ (Unicode U+2030, html entity ‰), which looks like a percent sign (%) with an extra zero at the end. It can be seen as a stylized form of the three zeros in the denominator, although it originates from an alteration of the percent sign.
A per mil is defined as:
- 1‰ = 10−3= 1⁄1000 = 0.001 = 0.1%
- 1% = 10‰
A per mil should not be confused with ppm (commonly pronounced "parts per mil" in the United States). A measurement in ppm means parts per million, and has as its denominator 1,000,000 and not 1,000.
Examples
Examples of common use include:
- Legal limits of blood-alcohol content for driving a road vehicle in some countries are 0.5‰ or 0.2‰.
- Seawater salinity. For example "the average salinity is 35‰".
- Tunnel and railway gradients (in some countries)
- Birth and death rates.
- Baseball batting averages, colloquially
- When used to describe property taxation, it is called the millage rate (U.S.) or mill rate (Canada).
- Used to describe stable-isotope ratios. For example "δ13C was measured at -3.5‰"
Related units
- Percentage point
- Percent (%) 1 part in 100
- Basis point (‱) 1 part in 10,000
- Parts-per notation
References
Categories:- Typographical symbols
- Typography stubs
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