Expert: Leslie - 6/25/2009

Question
Hello, I go round and round with this subject on a daily basis. The Chicago Manual of Style 14th Edition, section 8.3 plainly states write out whole numbers one through ninety-nine. I think it has become standard practice to write out numbers one through nine and then beginning with 10 use numerals however, in business/technical writing I am seeing more and more all numbers used numerically.  What is the correct way to use numbers in business writing? The references are not used scientifically but in a general way (i.e., "four documentation items were updated along with 17 citations" "Mr. SoandSo has twenty-five years of experience..." ). We write a lot of proposals referencing employee years of experience and report writing using numbers in a general way (non scientific). Thank you.

Answer
Brenda,

You are going to get just one more opinion from me. As you noted, most editors go round and round on this topic. You can submit questions on form to the editors of the Chicago Style Manual (CSM) http://www.chicagomanualofstyle.org/home.html who can provide you with authentic information.

The practice of writing out one through nine and using digits for 10 or more is an APA practice. Since APA is generally more popular than CSM, most writers think a double digit number as a numeral makes sense.

APA seems to have found what looks like a natural solution. I also am using the Gregg Manual for this opinion and the work I have been doing.

When comparing two numbers and one is an Arabic numeral, use the Arabic numeral for both: ...5 out of the 105 dentists....

When both numbers are below ninety-nine, spell both out: four out of five dentists.

Fractions are spelled out: ...two-thirds of the pie...

A number at the beginning of a sentence must be spelled out: One hundred and five of the 300....

If reading the text is easier with Arabic numerals, use them.

If the numbers are in tables, use Arabic numerals.

Proposals may be an exception especially if they are used in resumes or bios. CSM rules seem too stilted, and the importance of the numbers to draw attention to the accomplishments means that the Arabic numerals are often used.

As I mentioned, mine is only one opinion, for the authentic and final definition, you need to contact Chicago Style Manual.

BTW, most of the editors for publications such as the Government Publishing Office (GPO) standards and even the APA standards are available for questions.

Additionally, you can create your own business style manual based on one of these styles. You will need to document it and share it. I once had a boss who did not like the final comma before the conjunction in a list. When I edited his material, he became quite agitated with me. I showed him where the rules said a comma was needed based on our style manual, and he had the manual changed.

Leslie