Office of University Publications

Grammar and Style Guide

Time and Numbers

Century

Lowercase, spelling out numbers less than 10: the first century, the 20th century. For proper names, follow the organization’s practice: 20th Century Fox, Twentieth Century Fund, Twentieth Century Limited.

fractions

Use numerals to show fractions.

5 1/2, not “five and one-half”
75 3/4, not “75 and three-fourths”

months

Capitalize the names of months in all uses. When a month is used with a specific date, abbreviate only Jan., Feb., Aug., Sept., Oct., Nov., Dec. Spell out when using alone, or with a year alone.

First quarter classes will start on Sept. 1, 2005.
December is the busiest month for shopping.
The photo was taken in July 1988.

numbers

Spell out numbers one through nine and any number that begins a sentence.

John took six courses during fall quarter.
Seventy people showed up for the seminar.
There are 12 months in the year.

numerals of 1,000 and above

Use commas in the appropriate places, except for temperatures and years.

RIT has more than 14,000 students.
The boiling point of uranium is 3818°C.
She plans to retire in 2006.

time

Use figures except for noon and midnight. Use a colon to separate hours from minutes:

11 a.m.
1 p.m.
3:30 p.m.

Avoid such redundancies as 10 a.m. this morning, 10 p.m. tonight, or 10 p.m. Monday night. Use 10 a.m. today, 10 p.m. today, or 10 p.m. Monday.

The construction 4 o’clock is acceptable, but time listings with a.m. or p.m. are preferred.

When using a.m. or p.m., always lowercase, with periods.

time sequences

Spell out: 50 hours, 23 minutes, 14 seconds. When using the abbreviated form, as in sports statistics or similar agate use, or subsequent references, the form is 2:30:21.65 [hours, minutes, seconds, tenths, hundredths].

percent

One word. Use numerals when referring to percentages, unless the number is the first word of the sentence then spell out the number. Repeat percent with each individual figure

There will be a 7 percent increase in tuition this year.
Seventy five percent of RIT’s students live on campus.
He said 10 percent to 30 percent of the electorate may not vote.