Grammar: Numbers
The writer’s principal concern with numbers is knowing when to figure them and when to write them, and while errors in this respect are rarely as
serious as errors of punctuation, certain conventions have been established for ease of reading. These are set out below as they apply to the five
kinds of number (cardinals, ordinals, percentages, fractions and decimals). To begin, however, here are a few general points.
Firstly, with the exception of calendar years, sentences never begin with figures –
1979 was a memorable year in British politics. (Correct)
80% of people in the UK now own mobile phones. (Incorrect)
The second sentence should either have its opening number written –
Eighty per cent of people in the UK now own mobile phones
or be recast –
Mobile phone ownership in the UK now stands at 80%.
Secondly, whether written or figured versions are chosen, their uses should normally be consistent (£10,000 or ten thousand pounds, but not 10
thousand pounds). But an exception is made when consecutively written numbers can cause confusion –
Of the original thirty-six first-years, twenty-eight successfully completed
the course.
Greater clarity is achieved here by inconsistency –
Of the original 36 first-years, 28 successfully completed the course.
In such cases, it is usually the higher number that is figured –
He calculated that he would need 10 five-kilogramme bags of cement to
complete the job. (Clear)
He calculated that he would need ten 5-kilogramme bags of cement to
complete the job. (Less clear)
She bought a box of twelve 60-watt bulbs. (Clear)
She bought a box of 12 sixty-watt bulbs. (Less clear)
But where consecutively written numbers appear to be clear enough, the consistency rule applies.
Only six first-years attended the class last Wednesday
is not improved by –
Only 6 first-years attended the class last Wednesday.
Thirdly, unless they comprise a sequence of quantities, such as the National Lottery numbers, consecutively figured numbers do not make for easy
reading –
The concert hall can accommodate 900, 200 of whom are seated behind
the orchestra.
It would be wiser here to separate the numbers with intervening words –
The concert hall can accommodate 900 people, of whom 200 are seated
behind the orchestra.
Lastly, the writer’s safest guide is the nature of the script. Figured numbers will be the norm for the sciences and written numbers for the humanities.
Size
Whether cardinals are figured or written largely depends on their size, and most contemporary house styles adopt the following rules.
0
Apart from calculations, dates, lists and so forth, 0 is usually expressed with the word no –
There were no sheep in the field.
1–9
These numbers are always written unless they indicate items of a list, form part of a calculation or express measurements of height –
The three of them stood still and listened. (Correct)
The 3 of them stood still and listened. (Incorrect)
They had travelled only six or seven miles when the car broke down.
(Correct)
They had travelled only 6 or 7 miles when the car broke down.
(Incorrect)
The lecture was about the Four Ps of marketing. (Correct)
The lecture was about the 4 Ps of marketing. (Incorrect)
John is 5' 10" tall. (Correct)
John is five-feet ten inches tall. (Unnecessary)
10
Ten is optional. Some house styles (e.g. The Times’) treat it in the same way as 1–9 and write it, while others (e.g. The Guardian’s) treat it in the
same way as 11–99 and usually figure it.
11–99
These may be figured or written –
The twelve (or 12) jurors took less than an hour to reach their verdict.
There were approximately fifty-five (or 55) people in the lecture
theatre.
But figures are always used when the word to occurs to indicate a span between two numbers. Thus we would write –
There were 50 to 60 people in the lecture theatre
not –
There were fifty to sixty people in the lecture theatre.
Written cardinals from 21 to 99 are hyphenated –
thirty-seven
fifty-six
eighty-three
100+
Unless they appear in direct speech, cardinals over 99 are figured –
Over 400 people signed the petition.
There are 365 days in a year.
Reporters flocked to greet her at the end of her solo voyage of 8,000
miles.
Archaeologists suggest that civilisation emerged about 6,000 years
ago.
This week’s jackpot is worth £15m.
Writers tend to avoid large numbers in direct speech but, when they occur, they are written rather than figured –
‘Good God!’ said George, putting his pencil down on the table. ‘That
comes to thirteen thousand, four hundred and sixty-two pounds and
twenty-seven pence.’
Cardinals take commas with four or more digits in British English, and five or more in American –
1,000; 10,000 (UK)
1000; 10,000 (US)
Calendar years are an exception, taking no commas: 1066; 2012.
Sequences of quantity, lists, sums of money and units of measurement
These are always figured –
The sales figures for November and December were £12,642 and
£18,428 respectively.
The Four Ps of marketing are
1. Product
2. Place
3. Price
4. Promotion
The winning numbers in Saturday’s Lotto were 12, 16, 29, 31, 32 and
46. The bonus ball was 18.
Add 3oz of butter, 2tsp of flour and mix well.
Statistics
Numbers of people, animals and things over 10 are always figured when they are expressed as statistics –
They started with a small holding and four cows (non-statistical), but now
own a farm with over 60 head of cattle (statistical).
Pagination, dates and times
Pagination, dates and times of the day are always figured –
p. 147
3 October (UK standard)
October 3 (US and most UK newspapers)
3.45 p.m. or 3.45 pm (UK)
3:45 PM (US)
15:45 (digital clocks, UK and US)
Calendar years are always figured, even when they start sentences, unless they appear in direct speech –
2011 was a good year for the company.
The chairman rose and said, ‘Two thousand and eleven was a good year for the company’.
When indicating distances between pages and dates, the general rule is to use the least number of figures as possible, but some publishers (e.g.
the Modern Humanities Research Association)^{1 }always use the last two digits for the the later page –
pp. 256–7 or pp. 256–57
1997–9 or 1997–99
The exceptions are figures between 10 and 20 and dates that span decades and centuries, when the last two digits are always given –
pp. 12–13, rather than pp. 12–3
AD 10–11, rather than AD 10–1
1999–2001, rather than 1999–01.
Note that cardinals have replaced ordinals to express days of the month in dating letters (2 August, rather than 2nd August) and that the UK
ordering of dates is different from that of the US. The UK order is day, month and year, while the US order is month, day and year. Thus we would
write 14 March 2011 and the Americans, March 14 2011. (But most daily newspapers follow the American practice, the only exceptions being The
Guardian and The Independent.) Beware of the confusion that can arise when the month is also figured; 12.05.11 means 12 May 2011 in the UK and
December 5 2011 in the US. Note, too, the modern practice of omitting the comma between the month and the year.
These are written when they form part of a clause or start a sentence –
Twenty-six year old Victoria Smith yesterday won the prize for best
physics student
Victoria Smith, a twenty-six year old with two children, yesterday won
the prize for best physics student
and figured when they appear parenthetically in isolation –
Victoria Smith, 26, yesterday won the prize for best physics student.
But, as noted above, the numbers 1–9 (or 1–10) are always written –
Jamie, nine, was reunited with his parents yesterday, apparently no
worse for his ordeal.
Ordinal Numbers (Ist, 2nd, 3rd)
Size
Like cardinals, ordinal numbers are written or figured depending largely on their size (but see birthdays, anniversaries and days of the month below).
1st–19th
Unless expressed as dates, these ordinals are always written –
Everything was quiet at first and then all hell broke loose.
He was tenth in line for promotion.
20th–99th
These may be either figured or written –
Alaska was the 49th (or forty-ninth) state of the USA.
The rules of hyphenation are the same as for cardinal numbers; twenty-first to ninety-ninth.
100th +
Higher ordinals are always figured –
She was given a £500 cheque for being the millionth customer in the
shop.
Birthdays, anniversaries and days of the month
Birthdays and anniversaries up to and including ninety-ninth are optional –
The veteran MP celebrated her 75th (or seventy-fifth) birthday at
home
and figured at 100th and over –
2012 was the 100th anniversary of the sinking of the Titanic.
Dates of national and international importance, however, are properly written with upper-case initials –
Fourth of July
Fifth of November
September Eleven (but frequently 9/11).
As mentioned above, cardinals are now preferred when dating letters, but their use in other dating contexts is restricted by the fact that they cannot
be preceded by the definite article. For example, we can say the 28th, but not the 28. Thus we occasionally have to use ordinals –
We fly to Rome on the 18th of July, then on to Athens on the 28th.
Ordinal days are figured when the name of the month is given –
She looked in her diary and discovered that she had missed her
appointment for the 21st of June
and usually written when it is not –
She looked in her diary and discovered that she had missed her
appointment for the twenty-first.
Percentages are figured when they have statistical overtones. Elsewhere, they may be either figured or (more formally) written –
The survey showed that 80% of the population now own mobile phones.
(Correct: population is a statistical concept.)
The survey showed that eighty per cent (or 80%) of people now own mobile
phones. (Either is correct: people is a non-statistical concept.)
Note that per cent is written thus in British English and percent, in American.
N.B. Beware of two common errors with percentages. Firstly, a change in percentage points is not a change in per cent by the same number. If, for
example, interest rates increase from 3% to 4%, the increase is a rise of one percentage point, not 1% (the rise is actually 33.3%). Secondly, it
makesno sense to speak of a per cent (‘a in every hundred’) or half a per cent (‘half a in a hundred’). We need to write one per cent and a half per
cent.
Fractions are always written unless they appear in calculations or lists such as recipes –
Although he always looked busy, he probably wasted two-thirds of his
time.
Swansea scored the equaliser in the first minute of the second half.
Decimals are always figured unless (unusually) they start sentences or occur in direct speech –
The normal body temperature is 98.6° F.
He removed the thermometer from her mouth and held it up to the
light. ‘Ninety-eight point six’, he said. ‘Normal.’
To avoid misreadings, figured decimals of less than one should always include the nought (0.75 rather than .75).
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^{1} MHRA Style Book, Fifth Edition, Modern Humanities Research Association, 1996.