Numbers


 * CHAPTER 8: NUMBERS**

8.1 Introduction 8.2 General Rule for Numbers 8.3 Words or Numerals 8.4 Percentages and Money 8.5 Dates and Time of Day 8.6 Inclusive Numbers 8.7 Fractions 8.8 Plurals and Punctuation of Numbers 8.9 Measurements 8.10 Roman Numerals

8.1 INTRODUCTION This section deals with numbers as they are encountered in the course of writing for the MSPTC program and some examples from other disciplines as may be encountered in the profession of Professional and Technical Communications. Primarily, the section will cover when and whether numbers should be spelled out or shown as a numerical expression. Common issues with the punctuation of numbers in text will also be covered. It is very important to remember that convention will vary depending upon what style guide is being followed. This discussion draws primarily from //The Chicago Manual of Style// and the //MLA Handbook for Writers of Research Papers//. For an explanation of the most common style guides and their uses, please refer to the //Handbook of Technical Writing//. For a more detailed discussion of numbers in quantitative matter (e.g., tables and equations) please refer to Chapter 11: Editing Quantitative Material.

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8.2 GENERAL RULE FOR NUMBERS The following guidelines, taken from //Technical Editing// (198), are consistent among most style manuals.

1. Use figures for all quantifiable units of measure, no matter how small, rather than spelling out the numbers.


 * 2m ||
 * 12 hours ||
 * 0.3 cm ||

2. Do not begin a sentence with a numeral.


 * < ** Before Editing ** ||< ** After Editing ** ||
 * < // 2 // buildings will be erected on the site. ||< // Two // buildings will be erected on the site. ||

3. Don’t mix systems of measurement.


 * ** Before Editing ** || ** After Editing ** ||
 * The rug was //2 yards// wide and twelve feet long. || The rug was //six feet// wide and twelve feet long. ||

4. Set decimal fractions of less than 1.0 with and initial zero.


 * ** Before Editing ** || ** After Editing ** ||
 * The weight of the sample is //.67// ounces. || The weight of the sample is //0.67// ounces. ||

5. Convert treatment of numbers in translation according to usage in the country where the document will be used. For additional information see //The Chicago Manual of Style//, Section 5.202.
 * < **Number** || **Norwegian** || **British** || **American** ||
 * < 1,000,000 || million || million || million ||
 * < 1,000,000,000 || milliard || thousand million OR milliard || //billion// ||
 * < 1,000,000,000,000 || billion || //billion// || //trillion// ||
 * < 1,000,000,000,000,000 || billiard || thousand billion || quadrillion ||
 * < 1,000,000,000,000,000,000 || trillion || //trillion// || //quintillion// ||

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8.3 WORDS OR NUMERALS According to //The Chicago Manual of Style//, “consistency must sometimes give way to readability” (380). In technical contexts, spell out
 * whole numbers from one through one hundred,
 * round numbers, and
 * any number beginning a sentence.


 * **Before Editing** || **After Editing** ||
 * Twenty-three students formed //5// teams. || Twenty-three students from our classes formed //five// teams. ||
 * The oak tree is over //200// years old. || The oak tree is over //two hundred// years old. ||
 * //20// candidates are running for office. || //Twenty// candidates are running for office. ||

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8.4 PERCENTAGES AND MONEY Generally, percentages are shown as numerals followed by the word //percent//. However, in scientific and statistical copy, it is more common to use the symbol % after the numeral.


 * **Traditional Text** || **Scientific and Statistical Text** ||
 * The sale price is //50 percent// off the origianl price. || The survey showed that //50%// of participants did not agree with the results. ||

As a rule of thumb, if the number for an amount of money is written out, then the words dollar(s) or cent(s) are also written out. If numerals are used, either $ or ¢ are used, as appropriate.


 * **Before Editing** || **After Editing** ||
 * One piece of candy costs //75 cents//. || One piece of candy costs //seventy-five cents//. ||
 * The grocery bill was over //$150 dollars// this month. || The grocery bill was over //$150// this month. ||

Zeroes are included after the decimal point only if they appear in the same context with fractional amounts.


 * **Before Editing** || **After Editing** ||
 * The cost of the items was $0.85, $1.25, and //$20// respectively. || The cost of the items was $0.85, $1.25, and //$20.00// respectively. ||

Numerals are used for exact amounts or complex amounts.


 * **Before Editing** || **After Editing** ||
 * The catalog stated the cost as //two dollars and fifty cents// per unit. || The catalog stated the cost as //$2.50// per unit. ||
 * The final cost of the project was //three million five hundred sixty-three five hundred dollars//. || The final cost of the project was //$3,563,500.// ||

Words are used for indefinite amounts.


 * **Before Editing** || **After Editing** ||
 * The art is worth several //1,000// dollars. || The art is worth several //thousand// dollars. ||

Words and numerals are used for amounts over one million dollars.


 * **Before Editing** || **After Editing** ||
 * The equipment is valued at seven million nine hundred thousand dollars. || The equipment is valued at $7.9 million. ||

For amounts under one dollar, numerals are sued with //cents// written out, except if other dollar signs appear in the same sentence.


 * **Before Editing** || **After Editing** ||
 * The toll on this road is //twenty-five// cents. || The toll on this road is //25// cents. ||

For information about non-U.S. currency, see //The Chicago Manual of Style__,__// Sections 9.6 and 9.27.

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8.5 DATES AND TIME OF DAY Strictly numerical dates are not used. In the United States, dates follow the month-day-year convention and is now recommended by //Chicago// __//(//__253).

For more information on the usage of numerals in dates, see //The Chicago Manual of Style//, Sections 6.46 and 9.33//–//35. Numerals are used for most times of the day except quarter and half hours and in hours followed by //o’clock//. Colons are used to separate the hour from the minutes, followed by either a.m. or p.m. Colons are not used for the 24-hour system.
 * ** Before Editing ** || ** After Editing ** ||
 * 8/11/06 || August 11, 2006 ||


 * **Before Editing** || **After Editing** ||
 * Meet me at //two p.m.// tomorrow. || Meet me at //2:00 p.m.// tomorrow. ||
 * The meeting started at a //1/4 to twelve//. || The meeting started at a //quarter to twelve//. ||
 * Lunch will begin at //1/2 past eleven//. || Lunch will begin at //half past eleven//. ||
 * The work day ends at //5 o'clock//. || The work day ends at //five o'clock//. ||
 * Report for duty at //0730 a.m.// || Report for duty at //0730 hours//. ||
 * The lights went off at //2345 o'clock//. || The lights went off at //2345 hours//. ||

Do not use numerals to express noon or midnight, except in the 24-hour system. The time 12:00 p.m. is ambiguous.


 * **Before Editing** || **After Editing** ||
 * His shift ended at //twenty-four hundred hours//. || His shift ended at //2400 hours//. ||
 * The baby was born at //12:00 a.m//., February 12. || The baby was born at //midnight//, February //11–12.// ||

For more information on the 24-hour system, see //The Chicago Manual of Style//__//,//__ Section 9.44.

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8.6 INCLUSIVE NUMBERS Generally, for numbers 1//–//99, and for the number 100 and multiples of 100, numbers are given in full. For larger numbers, only the last two digits of the second number are given, unless more are necessary for clarity.


 * **1 through 99** || **100 and multiples of 100** || **Numbers larger than 100** ||
 * 2 //–// 3 || 100 //–// 104 || 103 //–// 04; 923 //–// 1003 ||
 * 21 //–// 48 || 1,100 //–// 1,113 || 1,608 //–// 774; 12,991 //–// 13,001 ||

For alternative systems for inclusive numbers, see //The Chicago Manual of Style//, Sections 9.65–68.

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8.7 FRACTIONS Simple fractions should be spelled out. Numerals are used to express a mixed number consisting of a whole number and a simple fraction. (For the treatment of fractions in mathematical expressions, see Chapter 11: Editing Quantitative Material.)


 * **Before Editing** || **After Editing** ||
 * I have already read //3/4// of the book. || I have already read //three-quarters// of the book. ||
 * //2/3// of the students are journalism majors. || //Two-thirds// of the students are journalism majors. ||
 * I need //six and 1/2// yards of fabric. || I need //6 1/2// yards of fabric. ||

For information regarding the treatment of numbers in mathematical type, see //The Chicago Manual of Style//, Chapter 14.

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8.8 PLURALS AND PUNCTUATION OF NUMBERS Plurals of a written number are formed by adding -//s//, -//es//, or by dropping the //y// and adding -ies (like any noun).


 * **Before Editing** || **After Editing** ||
 * The students were in their //twenty's and thirty's//. || The students were in their //twenties and thirties//. ||
 * The dealer dealt two //seven's// and three //six's//. || The dealer dealt two //sevens// and three //sixes//. ||

Plurals of numerals are formed by adding -//s//. Apostrophes are not used to form plurals of numbers.


 * **Before Editing** || **After Editing** ||
 * The book is an anthology of music from the 1990's. || The book is an anthology of music from the 1990s. ||

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8.8.1 en Dash vs. Hyphen Hyphens are used to separate numbers (expressed as numerals) that are not inclusive, such as telephone numbers, ISBNs, and social security numbers. En dashes are used to connect inclusive numbers (expressed as numerals).


 * **Hyphen** || **En Dash** ||
 * My telephone number is 123-456-7890. || The weekly reading includes pages 353 //–// 407. ||

En dash are not used if //from// or //between// precedes the first pair of numbers.


 * **Before Editing** || **After Editing** ||
 * Count from 1 //–// 10. || Count from 1 to 10. ||
 * The required total score must be between 200 //–// 250. || The required total score must be between 200 and 250. ||

For additional information about using the en dash, see //The Chicago Manual of Style//, Sections 6.83–86. For additional information about using the hyphen, see //The Chicago Manual of Style//, Sections 6.81–82; as well as Chapter 5 (Punctuation) of this Guide, section 5.2.

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8.8.2 Commas in Numbers Generally, a comma is used between groups of three digits, counting from the right. Commas are not used in
 * page or line numbers,
 * addresses, or
 * four-digit years.


 * **Commas** || **No Commas** ||
 * 1,000 || The index is on page 1019 of the book. ||
 * 400,000 || The hospital is at 2211 Mercy Drive. ||
 * 9,876,543 || What will Earth be like in the year 8000 CE? ||

For information about separating numerals using in the International System of Units, see //The Chicago Manual of Style,// Section 9.60.

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8.9 MEASUREMENTS Generally, units of measurement are expressed as numerals.


 * **Before Editing** || **After Editing** ||
 * I ran five miles. || I ran 5 miles. ||
 * The field is ten meters long. || The field is 10 meters long. ||

If numbers run together in the same sentence, one is written as a numeral and the other as a word.


 * ** Before Editing ** || ** After Editing ** ||
 * The site plan shows //6// 12-story buildings. || The site plan shows //six// 12-story buildings. ||

In mathematical, statistical, technical, and scientific text, physical quantities and units of time are expressed in numerals followed by an abbreviated form of the unit.


 * ** Before Editing ** || ** After Editing ** ||
 * The tea covered 50 kilometers in one day. || The team covered was 50 km in one day. ||

Documentation that includes measurement should follow these three systems taken from //Technical Editing// (198): the U.S. Customary System, the British Imperial System, and the International (metric) System. The accepted measures in the U.S. and Great Britain are the yard and the pound, but the expressions can vary. The International System of Units is a component of the metric system and is used for physical measurements. Its units are called SI units (for //Systeme International//, in French) (Rude p. 198). These are the seven fundamental units in the International System that are listed in the table below. **TABLE 8.1** (Rude p. 198)
 * **Quantity** || **Unit** ||  || **Abbreviation** ||
 * length || meter ||  || m ||
 * mass || kilogram ||  || kg ||
 * time || second ||  || s ||
 * electric current || ampere ||  || A ||
 * temperature || kelvin ||  || K ||
 * luminous intensity || candela ||  || cd ||
 * amount of substance || mole ||  || mol ||

Other SI units and symbols relevant to other subjects will be listed in that subject’s guidelines.   8.10 <span class="wiki_link">ROMAN NUMERALS

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;">According to //The Chicago Manual of Style// (397), a smaller letter before a larger one subtracts from its value, and a smaller letter after a larger on adds to it; a bar over a letter multiplies its value by one thousand. Roman numerals can also be written in lowercase letters. Roman numerals and their arabic equivalents are shown in table below.

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;">
 * TABLE 8.2** (//Chicago// p. 398)
 * = **Arabic** ||= **Roman** ||=  ||=   ||=   ||= **Arabic** ||=   ||= **Roman** ||=   ||= **Arabic** ||= **Roman** ||
 * 1 ||= I ||  ||   ||   || 16 ||   || XVI ||   || 90 || XC ||
 * 2 || II ||  ||   ||   || 17 ||   || XVII ||   || 100 || C ||
 * 3 || III ||  ||   ||   || 18 ||   || XVIII ||   || 200 || CC ||
 * 4 || IV ||  ||   ||   || 19 ||   || XIX ||   || 300 || CCC ||
 * 5 || V ||  ||   ||   || 20 ||   || XX ||   || 400 || CD ||
 * 6 || VI ||  ||   ||   || 21 ||   || XXI ||   || 500 || D ||
 * 7 || VII ||  ||   ||   || 22 ||   || XXII ||   || 600 || DC ||
 * 8 || VIII ||  ||   ||   || 23 ||   || XXIII ||   || 700 || DCC ||
 * 9 || IX ||  ||   ||   || 24 ||   || XXIV ||   || 800 || DCCC ||
 * 10 || X ||  ||   ||   || 30 ||   || XXX ||   || 900 || CM ||
 * 11 || XI ||  ||   ||   || 40 ||   || XL ||   || 1,000 || M ||
 * 12 || XII ||  ||   ||   || 50 ||   || L ||   || 2,000 || MM ||
 * 13 || XIII ||  ||   ||   || 60 ||   || LX ||   || 3,000 || MMM ||
 * 14 || XIV ||  ||   ||   || 70 ||   || LXX ||   || 4,000 || MV ||
 * 15 || XV ||  ||   ||   || 80 ||   || LXXX ||   || 5,000 || V ||

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 14pt; line-height: 115%;">8.10.1 In Names

Generally, use roman numerals for:
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> monarchs, sovereigns, emperors, and popes {//Elizabeth I//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> sequels to novels and movies {//Rocky II//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> different chapter titles with same topic {//Chapter 1. Gardening -I, Chapter 2. Gardening-II//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> boats {//Bluebird// //III//}

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> Generally, use ordinal numbers, if one hundred or less, for: <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> Personal names can be followed by a roman numeral or an arabic ordinal numeral {//John Smith III, or John Smith 3rd//} Arabic numerals are used in identifying labor unions and fraternal lodges {//United Steelworkers, Local 1295//} <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;"> <span style="font-family: Arial,Helvetica,sans-serif; font-size: 14pt; line-height: 115%;"> 8.10.2 In Addresses and Thoroughfares
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> successive dynasties, governments, and governing bodies {//Eighteenth Dynasty, Second Continental Congress//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> political or judicial divisions {//Sixteenth Precinct, Ninth Circuit//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> military units {//Sixth Infantry Division//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> places of worship {//First United Methodist Church//}

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;">Generally, use arabic numerals for: <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> Spell out, if one hundred or less, names of numbered streets {//Sixth Avenue//} The number of a building’s name is spelled out when it is its address {//Three Hundred Oak Lane//} <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> state, federal, and interstate highways {//Route 56//}
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;"> building numbers that precede street name {//23 Chandler Lane//}

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 10pt;">For additional information about technology and science abbreviations, see //The Chicago Manual of Style//, Sections 15.55–66.

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<span style="display: block; font-family: Arial,Helvetica,sans-serif; font-size: 14pt; text-align: left;">
 * WORKS CITED**

Alred, Gerald J., Brusaw, Charles T., Oliu, Walter E., //Handbook of Technical Writing//. 8th ed. Boston: Bedford, 2006.

//The Chicago Manual of Style//. 15th ed. Chicago: U of Chicago P, 2003.

Gibaldi, Joseph. //MLA Handbook for Writers of Research Papers//. 3rd ed. New York: MLA, 2003.

Rude, Carolyn D. //Technical Editing//. 4th ed. Boston: Allyn & Bacon, 2006.