218 THE FACTS ON FILE GUIDE TO GOOD WRITING of a number in the form of a superscript numeral (109 = billion, 1012 = trillion, etc.) after the first figure, or in less technical documents to make use of such vocabulary words as million, billion, and trillion. Note, however, that there is scope for confusion in what these words represent in terms of figures, as they are sometimes defined differently in France, the United States, Germany, and the United Kingdom.
Term in United States
Numeral
million billion trillion
1,000,000 1,000,000,000 1,000,000,000,000
When discussing such large figures, it is conventional to omit the final -s in the plural form (two million, six billion, three trillion). For further discussion of the use of commas with numbers, see COMMA (page 342), and the use of hyphens with numbers, see HYPHEN (page 350).
Dates Dates can be rendered in various different ways, some written out more fully than others. The most succinct way to render a date of the year is to reduce it to purely numerical form in the order: month of the year, day of the month, and year (as in 1/31/05 or 1.31.05). A less concise form, possibly less abrupt in character and thus more suitable for informal use, is to combine words and figures in the style of January 31, 2005. In imaginative writing it is usual to write out dates in full (the twenty-second of August). Years are usually rendered as figures and are rarely written out in full. In informal circumstances they may, however, be abbreviated to just two numbers in the belief that it is unnecessary to be more specific (back in ’98; the ’39–’45 war). Decades and centuries are commonly rendered in abbreviated form using a combination of words and figures. Examples of alternative styles for decades include the 1800s and the 1970s, as well as the fully written version (the seventeen-forties; the nineties). Note that there is no need to place an apostrophe before the s. Examples of the style for centuries, apart from the fully written style (the twenty-first century) include 21st century or 21 c. Years (and centuries) prior to the birth of Christ are labeled before Christ, abbreviated to B.C. Years after the birth of Christ are labeled anno domini (meaning “year of our Lord”), abbreviated to A.D. Note that B.C. and A.D. are often rendered in SMALL CAPITALS in printed texts. By convention B.C. comes after the date, while A.D. goes before the date (320 B.C.; A.D. 781). This last rule does not apply, however, in all circumstances, as for instance in built in the ninth century A.D. Note that there is an alternative dating system for years that avoids reference to the life of Christ, in which the initials B.C.E. (before common era) and C.E. (common era) follow the year. B.C.E. corresponds to B.C., while C.E. is the equivalent of A.D. In expressing a range of dates, as for instance in a person’s birth and death dates, the usual convention is to render them separated by a dash (1604–76). Note that in such cases there is no need to preface the figures with any introductory words such as from, to, or between. The same rule applies to figures in other kinds of number ranges (repeat 20–30 times, pages 73–78,