Editorial Style Guide
Styleguide Contents
Numbers
In General
The following guidelines apply to the majority of writing except for scientific, statistical, technical, and mathematical writing.
Spell out one to nine. Use numerals for 10 and above.
- When she turned 21, Sharon decided to pursue a career as a singer.
- Exceptions: Use numerals for percentages, decimals, credit hours, GPAs, book sections and pages, quantities combining whole numbers and fractions, and when symbols rather than abbreviations are used for units of measure. Also when spelled out numbers are clustered thickly in a sentence or paragraph, it is acceptable to use numerals instead.
We recommend using the word percent in formal running text and the percent sign (%) in tables, charts, scientific and statistical copy, and some informal and promotional copy. Most importantly, be consistent throughout a document.
- We printed the brochure on 8.5" X 11" paper.
- Suzanne carried 16 credit hours and earned a 3.8 GPA while spending 25 percent of her time at a work-study job that paid $5.75 per hour.
- The answer is in chapter 6 on page 289.
- More than 120,000 donors made gifts and pledge payments totaling $300 million, surpassing last year’s remarkable total by 16 percent.
- The pipe measured 6 ft. in length and had an inside diameter of 2.5 in.
Spell out large round numbers when possible.
- The museum houses over two hundred thousand artifacts.
Use a combination of numerals and words with numbers in the millions and larger.
- U-M libraries hold more than 8.2 million volumes.
Use a comma for numbers with more than three digits unless they represent SAT scores or years.
- Estimated undergraduate tuition for Michigan residents in 2006–07 was $9,723.
- The book, published in 2006, has 1,596 pages.
- John’s combined SAT score was 1082.
Spell out numbers at the beginning of a sentence or rephrase the sentence to avoid beginning with a number.
- Eighty-nine students received invitations to join the sorority.
Hyphenate fractions when they are spelled out:
- One-fourth of the class was out-of-state residents.
- Congress can override a presidential veto by having a two-thirds majority vote in both the House of Representatives and Senate.
Adjacent Numbers
When two numbers are adjacent to each other, use a combination of numerals and spelled-out numbers to help avoid confusion. Use a numeral if one of the numbers is a unit of measurement. Spell out the shorter of the two numbers if that is an option.
- The façade of Angell Hall features eight 3-story-high columns.
- The department printed 2,500 sixteen-page brochures.
Dates
In the U.S., date preference is for: month, day, and year, without ordinal letters.
- The university will be closed from December 25, 2007, to January 2, 2008.
- NOT The university will be closed from December 25th, 2007, to January 2nd, 2008.
- NOT The university will be closed from 25 December 2007, to 2 January 2008.
Footnote Numbers
Asterisks and superscripts follow punctuation marks (except a dash) in running text and are placed outside a closing parenthesis.
- Please enter your employee identification number,¹ your phone numbers (work and home)² with area code, and your U-M uniqname.³
Inclusive Numbers
When dealing with ranges of numbers (such as page numbers and years), carry over all the digits that change and include at least two digits for the second number. Use an en dash (–) rather than a hyphen with inclusive numbers.
- pages 1,022–36
- 2001–05
- 1835–1985
Unless the century changes, inclusive years should be styled with only the last two digits of the second number (1999–2000, but 2001–02). On publication covers, designers should use their discretion to achieve the desired look (2001–2002 versus 2001–02).
In running text, the en dash or hyphen should not be substitutes for the word to unless the numbers are in parentheses.
- She taught anthropology from 1964 to 1983.
- She taught anthropology at U-M (1974–83) and Yale (1967–74).
Metric Measures
Include metric measurements if you are writing for an international audience.
- The average summer temperature in Michigan is 72ºF (22ºC). Ann Arbor is about 800 feet (244 meters) above sea level.
Money
In general: When a relation between two or more similar amounts is expressed, the dollar symbol may or may not be repeated, but use a hyphen to denote range. If fractional amounts over one dollar are used in any reference, be consistent and use them throughout, even if it’s a zero amount.
- Ticket prices range from $16.50 to $45.00.
- He committed $3–4 million in start-up capital for the business venture.
More Than One Kind of Number in a Sentence
When you have numbers in a sentence that refer to more than one class of things, you do not need to make all the numbers numerals if numbers in one of the categories do not exceed nine.
- The control panel of the testing equipment had 12 function buttons, 18 control knobs, and four display modules.
Multiple Numbers in a Sentence
If a sentence includes multiple numbers that apply to the same category of thing, and if one of the numbers must use a numeral, use numerals for all the quantities of that category.
- Candidates for student government positions included 12 biology students, 9 political science students, 8 music students, and 7 students from five other majors. (Spell out five because it identifies number of majors, not number of students.)
Ordinal Numbers
Spell out ordinal numbers from first to ninth.
- She placed fourth out of 525 competitors.
- The 21st century will bring an even greater rate of technological advancement than was seen in the 20th century.
Room Numbers
Campus room numbers should be referred to with the name of the building and the room number, in that order.
- The Office of Financial Aid is located in the Student Activities Building, room 2011.
Telephone Numbers
Always include the area code with phone numbers. Many U-M units use parentheses to set off area codes, however hyphens, no punctuation or (at the designer’s discretion) other symbols are acceptable as long as you are consistent with their use throughout.
734-764-1817
(734) 764-1817
734•764•1817
Time
Use numerals with a.m. and p.m. (small caps or lowercase letters) to indicate specific times. For clarity, use noon and midnight in place of 12:00 p.m. and 12:00 a.m. Spell out the hour when using o’clock.
- The lecture will begin at 10:30 a.m.
- Professor Stanek will extend her office hours to five o’clock this week.
Years and Decades
In running text, spell out the decade or use the full numeric decade. Use the abbreviated numeric decade format in very informal copy or in lists where space is limited. Do not use an abbreviated format if there could be any confusion about the century. Do not use an ’s in numeric decades (1880s or ’80s, not 1880’s or ’80’s).
the eighties
the 1880s
the ’80s
Use the correct placement for A.D. and B.C. (small caps) and their equivalent terms, C.E. and B.C.E. (“common era” and “before the common era”).
- Hannibal died in 183 B.C.
- King George IV died in A.D. 1830.
Inclusive years within the same century should be styled with only the last two digits of the second number (1963–68, 1432–57). If the date range covers a century change, use all four digits (1695–1802, 1998–2004). On publication covers, designers should use their discretion to achieve the desired look (2007–2008 versus 2007–08).