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number format in reports, again

number format in reports, again

number format in reports, again

This was discussed back around 2005 or 2006.  There were some well thought out opinions, but no real references, or even a concensus.
"What is the correct way to express numbers in a technical   report?
Here are a couple of examples for discussion purposes:
Two (2) samples should be obtained and 3 tests should be conducted.
Fifty (50) samples should be obtained and 75 tests should be conducted."

I've spent a little time looking for MIL spex, etc, hoping to find a short cut around the debate and endless report reviews, but have not found anything yet.


Dan T


RE: number format in reports, again

There have been so many discussions it's hard to know where to start.  Lately I have been using a standard for specification writing from the Department of Construction and Infrastructure, Northern Territory Government, AU. I know, it's not the same as a report and it's not a reference published in my location.  But it makes sense and it's simple to remember.

Use numbers instead of words, except when one number follows another. (Use dash to separate).
Provide 6 copies
Use five - 12mm bolts
Do not repeat a number in brackets.
for example, Provide six (6) copies

I like the rule, despite the reference refering to parentheses as brackets.


"Gorgeous hair is the best revenge."  Ivana Trump

RE: number format in reports, again

I've struggled with the second one forever.  "Use 5 12 mm bolts" sucks, "Use five 12 mm bolts" isn't a lot better, but your reference's "Use five-12 mm bolts" seems crystal clear.  I've never been much for style guides, but I'm using that particulat "standard".


RE: number format in reports, again

I often refer to the NIST style guide for issues such as this.

See http://physics.nist.gov/Pubs/SP811/sec07.html, section seven-point-six (ha) gives guidance on this matter in particular.

Additionally, I recall one of my old English Language teachers suggesting that in prose, that any number over 12 (maybe including twelve?) should be written as a word instead of a value. Never really found anything that corroborates this, though I've never really looked either!

RE: number format in reports, again

thanks !

eng1ne, I've seen a few references that suggest, at least for general audiences, the opposite of your (old English, olde English (?)) teachers suggestion.
That is, small numbers be spelled out. One, ten, 100.

Dan T

RE: number format in reports, again

The example five-12 mm bolts is clear but grammatically incorrect.  The hyphen declares that five is an adverb modifying the adjective 12.  In reality five is an adjective modifying bolts, and 12 is the adverb modifying the adjective mm, which intern also modifies the noun bolts.  Grammatically correct it should read: five, 12-mm bolts. The comma declares that five modifies bolts and not 12-mm.   Spelling out five, declares it an integer or number of undividable objects, and 12 in numerals declares it a dimension with significant digits.  "Five, 12-millimeter bolts" is crystal clear to me and grammatically correct.

A side note, in reports I generally don't abbreviate units of measure, because clarity is everything.  In the example above, by spelling out millimeters and using the hyphen correctly all ambiguity is removed even if you forget the comma.  

Specifications are whole different ball game because they are legal documents, and all grammar is null and void when it comes to legal documents.  If I were to review a report that reads like a contract, I'd file it in the circular cabinet.  

RE: number format in reports, again

Like I said, writing specifications is an entirely different animal.  I ran across the Australian reference and just liked the clear-cut rules.  No BS, no handwringing about 'proper' this and 'proper' that, no justification blah, blah, blah.

I don't think I'd call specifications legal documents.  This guide is in the form of written directions to the specifier and reads much like what they are requesting using a minimum of words written in plain language with precis, everyday language.  It specifically states to avoid using legal or commercial phrases.

"Gorgeous hair is the best revenge."  Ivana Trump

RE: number format in reports, again

I'll get on my accuracy/liability soapbox (yet again!).

When you use "one (1)" you have a greater risk in editing to change one or the other but not both...thereby increasing your liability with an inaccurate document.

Drew08 is correct about the 5, 12-mm bolts; however, the hyphen is superfluous and not necessary.  It would then be 5, 12mm bolts.

The rule I've tried to follow with regard to "spelling out" numbers is that if it is ten or less, it gets spelled out.  If greater than ten, it gets a number such as 12.  I also try to not mix spelled out and numerical in the same sentence or paragraph, with the numerical winning the battle.  For example: " There were 10 occurrences of the 87 percent relative humidity....".  I also do not like symbols in the text of my reports....as an example I wrote in the previous example 87 percent instead of 87%.

I have not idea what is correct.  I just try to be consistent in my writing.  I just finished a textbook and the editors don't follow any of my conventions...oh well.

RE: number format in reports, again

Isn't this clear 5 bolts(12mm)?  In the brackets could whatever specification necesary.

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