Thompson Rivers University
Thompson Rivers University

Numbers

General rules

In running text, spell out numbers one through nine. For 10 and above use numerals.

Always use numerals for:

  • measurements that use abbreviations or symbols, e.g. 5 km, 2 L, 9˚C
  • percentages, e.g. 50%
  • quantities consisting of whole numbers and fractions, e.g. 1½
  • course units, e.g. (3)
  • grade-point averages, e.g. 4.33
  • currency, e.g. $5

One important exception: always spell out numbers that begin sentences.

For numbers in official names, follow the organization’s spelling style even when it is at odds with TRU practice.

Ordinals

The above practices apply to ordinal numbers as well. Spell out ordinal numbers when referring to year of study.

Surita is in her fourth year of study.

When using the abbreviated form of ordinals, place numerals and letters on the same line. Do not use superscript.

45th anniversary

Streets that are named with ordinals should also follow the general rule.

Third Street, 37th Avenue

Numbers with four or more digits

In numerals with four or more digits, use commas to separate groups of three digits except house, telephone, page, year and other serial numbers.

1,200; 1198 Columbia Street; 1-800-828-5000

Very large numbers can use a mixture of numerals and spelled out numbers.

2.3 million, 458 billion

Currency

Always use numerals to express currency. Canadian currency is expressed in numerals accompanied by the appropriate symbols ($ and ¢). There is no space between the currency symbol and the numeral.

Two second-year arts students were awarded $5,000.

Note that zeros after a decimal point should only be used if they appear in context with other fractional amounts.

Prices ranged from $0.95 to $1.00.

Very large amounts may be expressed with a mixture of numerals and spelled-out numbers and should appear with the currency symbol.

$4 million, $8.97 billion

When referring to foreign currency in specific numerical amounts, use the three-letter currency code (in upper case) instead of the currency symbol.

USD 42.78
EUR 123.00

Decimals

Use a zero before a decimal point when the value is less than one.

0.5, –0.62

Fractions

Use fraction characters (or superscript/subscript) whenever possible instead of full-sized numerals separated by a slash.

not 8 1/2

Simple fractions that are not mixed numbers should be spelled out.

the first half of the semester; one third of students

When a fraction is considered a single quantity, it is hyphenated.

She has read three-quarters of the book.
This is a half-hour lecture.

However, when the individual parts of a quantity are in question, the fraction is spelled without the hyphen.

We cut the sample into four quarters.

Quantities consisting of whole numbers and fractions should be expressed in numerals.

8½ x 11 in. paper

Percentages

Percentages should be given in numerals. If the text includes numerous percentage figures, the symbol % is appropriate. Otherwise, use the word “percent”. In tables, it is acceptable to use the symbol.

The minimum grade required in English 12 varies from 67% to 80%.
Ten percent of students are Aboriginal and over 14 percent are international.

There is no space between the numeral and the symbol %. In the second example, "Ten" is spelled out following the general rule to always spell out numbers that begin sentences.

Plurals of numerals

Spelled-out numbers form their plurals like other nouns.

the terrible twos
Bad things always happen in threes. 

Ranges (inclusive numbers)

An en dash (a dash slightly longer than a hyphen) between two numbers implies “up to and including” or “through”. 

Please refer to pages 45–72.

See Punctuation and spelling: Dashes and hyphens.

If “from” or “between” is used before the pair of numbers, the en dash should not be used; instead, “from” should be followed by “to” or “through”, and “between” should be followed by “and”.

from 45 to 63
between 1898 and 1910 

Dates and time

The following rules for dates and times apply in running text. In promotional design as well as in tables, forms or graphs where space is extremely tight, short forms and figures may be used.

Formatting dates

Specific dates in running text may be written in either of two ways.

Saturday, Sept. 19, 1998
Wednesday, 25 November 1999

For an all-numerical date format, use year-month-day, as recommended by the Government of Canada, the Standards Council of Canada and ISO 8601. This format is intended particularly for electronic formats that sort by date; all-numerical date formats should not be used in running text.

2014-02-25

Abbreviating months

Abbreviate only Jan., Feb., Aug., Sept., Oct., Nov. and Dec. Spell out when standing alone or with year alone.

December 2009
Convocation is on Oct. 16
August is a hot month 

Academic year

Indicate the academic year according to this format:

2014/15

Centuries and decades

When writing about centuries, spell out the first nine centuries as words, and use digits for 10 and above.

the fifth century; the 19th century

Decades may be spelled out (as long as the century is clear) or expressed in numerals.

the nineties, the mid-1990s, the ’90s

When writing the names of decades in numerals, do not use an apostrophe before the plural “s.” An apostrophe precedes the shortened numerical form of the decade. See Plurals vs. Possessives: Plurals for letters, abbreviations and numbers.

Holy days and holidays

Use the word “holidays” to refer to statutory holidays and non-religious holidays. Use the term “holy days” to refer to dates marked by religious observances.

Hours

In TRU Style, hours are usually written numerically, with no zeros for times on the hour. The abbreviations a.m. and p.m. are in lower case with periods (see Abbreviations, Acronyms and Initialisms: Lower case). The periods may be left out for promotional materials such as posters not using running text.

Class ends at 5:30 p.m.
Convocation begins at 10 a.m. and ends at noon.
John teaches the eight-thirty lab.

Use noon and midnight rather than the (incorrect) forms 12 p.m. or 12 a.m., or 12 noon (the 12 is redundant).

Where necessary, time zones are given in parentheses.

9 a.m. (PST)

Ordinals

When writing dates without the year, do not use the ordinal form.

Feb. 15 (not Feb. 15th)

Ranges of dates

When writing about periods of time over years, write the numbers out using an en dash (a dash slightly longer than a hyphen) not a slash (except the academic year).

1985–1990 or 1985–87 (not ’85–’90)
2000–2001 (not 2000–’01 or 2000/2001) 

A range of times is written using the words “from” and “to” in text but with an en dash in tables.

The reception is scheduled from 8 to 11 p.m.
Reception, 8–11 p.m.

See also Punctuation and spelling: Dashes and hyphens.

Measurements

If an abbreviation or symbol is used for the unit of measure, the quantity is always expressed as a numeral.

Metric abbreviations

Metric measurement abbreviations should appear in lower case with no periods, except for the abbreviation for “litres,” which should be capitalized to avoid confusion with the numeral 1. Use one space between the numeral and the abbreviation for the unit of measure.

5 km, 20 ml, 9 L

Abbreviating imperial measurements

Customary (imperial) measurement abbreviations should appear in lower case, with a space before and a period at the end of each unit. In running text, use the abbreviations "ft." and "in." rather than using a single quotation mark for foot and double quotation marks for inch.

6 in., 24 ft., 36 sq. in., 12 mi., 5 lb.

Temperature

Celsius is abbreviated as a capital.

It was 28˚C yesterday.

Using superscripts

Square measures may be expressed as "sq m" or with the superscript: "m2". The latter form is to be used in scientific or technical text. Cubic measures should be expressed using the superscript. 

6 m3

Roman numerals

Monarchs, emperors and popes with the same name are differentiated by Roman numerals.

Elizabeth II, Louis XIV

Roman numerals are also used to designate the sequel to a novel or movie.

Rocky IV

Telephone numbers

Domestic telephone numbers should be separated with hyphens. No parentheses should be used around area codes.

250-828-5000

800 numbers should be written as follows:

1-800-828-5000

International phone numbers are expressed in the ITA standard format.

+22 609 123 4567

The international prefix symbol (+) precedes the country code, which is then followed by the area code and telephone number.