Numbers

Cardinal and Ordinal Numbers

In most cases, spell out figures from zero through nine except in cases such as scientific matter dealing with physical  quantity, scores for sporting events, or when speaking of academic credit or course numbers. Always use figures with percent.

one course
two sequences
three terms
two semesters

    but

1.5 milliliters
0.3 credits
HIST 101
5 percent

Write numbers 10 and greater as numerals.

There were more than 200 students in GEOL 102 last term.

Write out numbers at the beginning of a sentence, or rewrite the sentence so that it doesn’t begin with a number.

Nineteen thousand students registered for winter term classes.

The winter term enrollment was 19,000 students.

With the exception of years and test scores, four-digit and greater numbers should always have a comma after the thousand position.

1,000
    not
1000

With the exception of first through ninth, do not spell out ordinal numbers.

Gwen stole second base in the top half of the first inning.
18th- and 19th-century literature is his specialty.

Dates

Don’t use a comma in dates giving only the month and year.

January 1995

Use two commas to set off the year in dates giving the month, day, and year.

Does July 5, 1909, ring a bell?

Use an en dash instead of a hyphen between the first and second number to denote inclusive dates. When the century or the millennium changes, all the digits are repeated.

The 1999–2000 catalog is missing from the archive.
She served a term in 2000–2001.

When writing inclusive dates between, for instance, 2001 and 2009, don’t include the 0 after the en dash (zero is a place holder with no value).

The professor was on leave during 2006–7.

Inclusive dates after 2009 revert to the two-digit standard.

The provost returns for the 2015–16 academic year.

Please refer to The Chicago Manual of Style, Section 9.63, for other rules on writing inclusive years.

Except in formal invitations, use cardinal rather than ordinal numbers for the date.

The ceremony is scheduled for October 16, 2001.
    but 
You are cordially invited to attend the inauguration of the President of the United States on the Sixteenth of January, Two Thousand and Sixteen.

In general, don’t use on with a date or day. Occasionally you need to include on to avoid confusion.

Commencement will be Saturday, June 12.
    but
He performed in 1776 on August 12, 2012.

Enumeration

Items can be enumerated in lists by using numbers followed by periods. See also Parentheses, under Punctuation, for enumeration within a text.

1. Be brief
2. Be clear
3. Be prompt
4. Be ready

Full-Time Equivalent

Enrollment and employment statistics are often stated in terms of full-time equivalents (FTE). Use only one digit after the decimal point.

1.0 FTE is full time
0.5 FTE is half time

Grade Point Average

Carry grade point averages to two digits after the decimal (e.g., 3.50). See also Academics.

Money

Use figures for fractional amounts of more than one dollar. Use zeros after the decimal point for whole-dollar amounts only when they appear in the same context with fractional amounts.

The ticket prices are $5.00 for general admission, $3.50 for students and senior citizens.
$7.95
$2
$10
$579
$4,020
$100,000
$1.5 million

In tables, use one format—either with or without decimals—consistently. Use a label (e.g., Dollars) to avoid repeating the same symbol (e.g., $) over and over.

More Than, Fewer Than

Don’t use over or under when referring to numbers; use more than or fewer than.  Over  and under refer to spatial relationships. More than and fewer than refer to quantity or to units you can count. See also less or fewer and over or more than under Troublesome Terms.

More than 16,000 students received the letters.
Fewer than a dozen students received the letters.

Percent

Percent is one word. Always use figures with it. Use decimals, not fractions. The % symbol may be used in scientific data or tables.

8.25 percent [not 8-1/4 percent]

See also Percent and Percentage under Plurals.

Telephone and Facsimile Numbers

In your writing, tailor telephone numbers to your audience. Every phone number on the University of Oregon telephone system begins with area code 541- followed by the three-digit prefix 346-, then four additional digits. On‑campus phone calls require five digits (6 + last four digits). The same principles apply to facsimile (fax) numbers. Separate numbers with hyphens, not dots.

6-5396
541-346-5396
800-232-3825 [not 800.232.3825]