Number spans (such as page ranges) are often abbreviated – for example, 42–43 as 42–3 and 123–128 as 123–8. This is known as number-span elision, abbreviating (or condensing) inclusive numbers, number abbreviation, and, more informally, as digit-dropping.
Not only are there different names for this custom, there are different styles too. The scripts described on this page deal with the styles set out in the style guides of Chicago University Press (The Chicago Manual of Style, pp. 759–60) and Oxford University Press (New Hart's Rules: The Oxford Style Guide, pp. 590–1). The CMS rules are widely used, the OUP style is more popular in Britain. The differences between the two are best summarised by the following table (examples based on those in the CMS, some added to show OUP style):
| Example | CMS | OUP |
| 3–10 12–18 71–72 96–117 100–104 1100–1113 101–108 808–833 1103–1104 321–328 498–532 1013–1019 1087–1089 1496–1500 11564–11615 12991–13001 |
3–10 12–18 71–72 96–117 100–104 1100–1113 101–8 808–33 1103–4 321–28 498–532 1013–19 1087–89 1496–1500 11564–615 12991–13001 |
3–10 12–18 71–2 96–117 100–4 1100–13 101–8 808–33 1103–4 321–8 498–532 1013–19 1087–9 1496–1500 11564–615 12991–3001 |
The general idea is that in the OUP style as many digits as possible are dropped but teens are maintained (11–17, not 11–7). The CMS stipulates that digits are dropped only when the first number is greater than 100; no digits are dropped when the first number is a multiple of 100; in ranges 101–109, 201–209, etc. only the changed part is used (101–8, 1203–4); ranges of 110 through 199, 210 through 299, etc., two or more digits remain: 321–28, 1087–89. All styles stipulate that spans that cross centuries aren't abbreviated (1997–2002).
The scripts are set up in such a way that they target a particular paragraph style, namely, Running Header. The main reason for restricting the scope of the scripts is that they often cannot be used indiscriminately; for example, number ranges are usually not abbreviated in titles and headings; dates that cross the boundary of a century aren't elided (1992–2004); and spans in years BC are not abbreviated in order to avoid ambiguity.
To target a different character style, change line 4 of the script, where it now says
var pstyleName = 'Running Head';
Replace 'Running Head' with the name of the style you want to target.
To run the script indiscriminately anyway, in an index, for instance, simply make sure that the paragraph style coded in the scipt is not in the document.
You can use plain dashes and en rules in number ranges, the scripts match both.
8 Jan. 2023: Fixed some errors in the description (thanks to Marc Autret for spotting them).
29 Nov. 2020: Fixed a bug in the CMS version.
9 Sept. 2017: First posted.
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To download a script, right-click the link, then select Save Link/Target As.
OUP-style script: drop_digits_OUP.jsx
CMS-style script: drop_digits_CMS.jsx
Safari users: the downloaded file will get the .txt extension, as in drop_digits_OUP.jsx.txt. Simply remove that extension so that you get drop_digits_OUP.jsx and InDesign recognises the script.
Installing and running scripts
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