Write numbers up to ten in full. Use digits from 11 upward. However, be consistent, so write ‘…7, 18 and 21’ where these appear together.
If a number appears at the start of the sentence, write it out in full.
Always use digits when talking about pages or measurements (4 kilometers, on page 2).
In general, use commas as the thousand separator for figures exceeding 999 (e.g. 2,657 and 12,340) unless this causes significant formatting problems (e.g. Excel). In this case, leave as in the source text. (NB: 2’152’458 is NOT correct!)
Use million, billion and trillion if there is space, otherwise mn, bn and trn.
Hyphenate fractions in texts, e.g. two-thirds, four-fifths, ten-and-a-half years old.
Write dates out in full wherever possible using the following format, which is used consistently in Europe and is easily recognizable worldwide:
Friday, 1 December 2007
You may abbreviate the month to three letters if space is limited, e.g. 1 Jan 2008.
Numeric dates should be used only in tables, i.e. where the full form is inappropriate for reasons of limited space: 01.12.07
The use of the numeric US date format can be misleading for European audiences, and vice versa, which is why we prefer to limit its use: 12/1/2007 is December 1, 2007, NOT 12 January 2007.
Recently, the format yy/mm/dd has become widespread: 2007-12-01, meaning 01 December 2007.
Use the 24-hour clock in business texts, e.g. 13:50. Separate the hours and minutes with a colon as in the example, and add a leading zero where necessary, e.g. 09:05
Add CET, EST, etc. if the time zone needs to be specified.
In more personal texts, such as client invitations to events, use ‘a.m.’ (morning) and ‘p.m.’ (afternoon) for reasons of style.
+41 (41) 444 5555.
Acceptable abbreviations: t for telephone, f for fax, m for mobile (NOT ‘mob’ or ‘c’))
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