Student's guide to writing college papers, Fourth edition - Kate L. Turabian 2010

Numbers
Titles, names, and numbers
Style

23.3.1 Words or Numerals?

23.3.1.1 The General Rule

Spell out numbers from one through one hundred. If the number has two words, use a hyphen (fifty-five). Also spell out round numbers followed by hundred, thousand, hundred thousand, million, and so on. For all other numbers, use arabic numerals. Follow this pattern for numbers that are part of physical quantities (distances, lengths, temperatures, and so on), and do not use abbreviations for the units in such quantities.

After seven years of war came sixty-four years of peace.

The population of the three states was approximately twelve million.

He cataloged more than 527 works of art.

Within fifteen minutes the temperature dropped twenty degrees.

If your topic relies heavily on numerical data, follow a different rule: spell out only single-digit numbers and use numerals for all others.

Use the same principles for ordinal numbers ( first, second, etc.) that you use for standard ones. Add st, nd, rd, or th as appropriate.

On the 122nd and 123rd days of his trip, he received his eighteenth and nineteenth letters from home.

23.3.1.2 Special Cases

Initial Numbers

Never begin a sentence with a numeral. Either spell out the number or recast the sentence, especially when there are other numerals of a similar type in the sentence.

Two hundred fifty soldiers in the unit escaped injury while 175 sustained minor injuries.

Of the soldiers in the unit, 250 escaped injury and 175 sustained minor injuries.

When spelling out numbers over one hundred, omit the word and within the term (two hundred fifty, not two hundred and fifty).

Series of Numbers

Ignore the general rule when you have a series of numbers in the same sentence that are above and below the threshold, especially when those numbers are being compared. In these examples, all are expressed in numerals.

Of the group surveyed, 78 students had studied French and 142 had studied Spanish for three years or more.

We analyzed 62 cases; of these, 59 had occurred in adults and 3 in children.

23.3.2 Inclusive Numbers

To express a range of numbers, such as pages or years, give the first and last (or inclusive) numbers of the sequence. If the numbers are spelled out, express the range with the words from and to; if they are expressed in numerals, use either these words or a connecting hyphen with no space on either side. In citations, always use hyphens (see chapters 18—20).

from 45 to 50 NOT: from 45—50

45—50 NOT: forty-five-fifty

For inclusive numbers of one hundred or greater, use full numbers on both sides of the hyphen (245—280, or 1929—1994).

23.3.3 Percentages and Decimal Fractions

Use numerals to express percentages and decimal fractions, except at the beginning of a sentence. Spell out the word percent, except when you use many percentage figures and in the sciences, where the symbol % is usually preferred (with no intervening space after the number). Notice that the noun percentage should not be used with a number.

Scores for students who skipped summer school improved only 9 percent. The percentage of students who failed was about 2.4 times the usual rate.

Within this system, the subject scored 3.8, or 95%.

When you use fractional and whole numbers for the same type of item in the same sentence or paragraph, give both as numerals.

The average number of children born to college graduates dropped from 2.4 to 2.

Put a zero in front of a decimal fraction of less than 1.00 if the quantity expressed is capable of equaling or exceeding 1.00; otherwise, omit the initial zero.

a mean of 0.73

a loss of 0.08

p < .05

For fractions standing alone, follow the general rule for spelling out the parts (see 23.3.1). If you spell the parts, include a hyphen between them. Express in numerals a unit composed of a whole number and a fraction, with no intervening space between these items.

Trade and commodity services accounted for nine-tenths of all international receipts and payments.

One year during the Dust Bowl era, the town received only 15/16 of an inch of rain.

The main carving implement used in this society measured 2½ feet.

23.3.4 Money

If you refer only occasionally to U.S. currency, follow the general rule (see 23.3.1), and spell out the words dollars and cents. Otherwise use numerals along with the symbol $ or ¢. Omit the decimal point and following zeros for whole-dollar amounts, unless you refer to fractional amounts as well.

Rarely do they spend more than five dollars a week on recreation.

The report showed $135 collected in fines.

After peaking at $200.00, shares of the stock plummeted to $36.75.

Express large round numbers in a combination of numerals and words.

The deficit that year was $420 billion.

23.3.5 Time

For references to times of day in increments of an hour, half hour, or quarter hour, spell out the times. If necessary, specify in the morning or in the evening. You may use o'clock, although it is now rare in research writing.

The participants planned to meet every Thursday around ten thirty in the morning.

When emphasizing exact times, use numerals and, if necessary, a.m. or p.m. (lowercase, roman, no intervening space). Always include zeros after the colon for even hours.

Although scheduled to end at 11:00 a.m., the council meeting ran until 1:37 p.m.

In either situation, use the words noon and midnight (rather than numerals) to express these specific times of day.

23.3.6 Addresses and Thoroughfares

Follow the general rule (see 23.3.1) for the names of local numbered streets. State, federal, and interstate highways are always designated with numerals, as are street or building addresses and telephone and fax numbers. Note that the elements of a full address are separated by commas, except before a zip code.

The National Park Service maintains as a museum the house where Lincoln died (516 10th Street NW, Washington, DC 20004; 202—426—6924).

Ludwig Mies van der Rohe designed the apartments at 860—880 North Lake Shore Drive.

Interstate 95 serves as a critical transportation line from Boston to Miami.

23.3.7 Dates

23.3.7.1 Month, Day, and Year

Spell out the names of months when they occur in your text, whether alone or in dates. Express days and years in numerals, and avoid using them at the beginning of a sentence, where they would have to be spelled out (see 23.3.1.2). Do not abbreviate references to the year (“the great flood of '05”).

Every September, we recall the events of 2001.

NOT: Two thousand one was a memorable year.

For full references to dates, give the month, the day (followed by a comma), and the year, in accordance with U.S. practices. If you omit the day, omit the comma. Also omit the comma for dates given with seasons instead of months; do not capitalize the names of seasons.

President John F. Kennedy was assassinated on November 22, 1963.

By March 1865 the war was nearly over.

The research was conducted over several weeks in spring 2006.

23.3.7.2 Decades, Centuries, and Eras

In general, refer to decades using numerals, including the century (1920s not 20s). If the century is clear, you can spell out the name of the decade. The first two decades of any century do not lend themselves to either style and should be described fully for clarity.

The 1920s brought unheralded financial prosperity.

During the fifties, the Cold War dominated the headlines.

Many of these discoveries were announced during the first decade of the twenty-first century.

Refer to centuries using either numerals or lowercase spelled-out names. If the century is spelled out and used as an adjective preceding a noun that it modifies, as in the second example, use a hyphen; otherwise, do not.

The Ottoman Empire reached its apex in the 1600s.

She teaches nineteenth-century novels but would rather teach poetry from the twentieth century.