numbers: comparative and inclusive numbers

Follow the guidelines below when writing comparative and inclusive numbers.

Comparisons

For general comparisons note the following:

• five times as great (not five times greater)
• one fifth as large (not five times smaller)

Note that “a four-to-one margin” is meaningless; “a margin of three” is correct.

Consecutive numbers

Consecutive numbers are joined by or or and, except where intermediate quantities are possible:

• row 5 or 6
• rows 5 and 6

but

• a range of 5 to 6 (rather than a range of 5 or 6)

In references to successive pages, p. 15, 16 indicates matter that is disconnected in the two pages, whereas pp. 15–16 indicates that the subject is continuous from the first page to the second.

Inclusive numbers

Opinions differ on the proper forms for inclusive numbers written as numerals. Of course, it is always acceptable to write both numbers in full.

However, if you want to abbreviate the second number, follow the principles below to ensure clarity.

Repeat all digits in numbers below 100:

• 4–10
• 67–68
• 82–99

Repeat all digits where the first number is 100 or a multiple of 100:

• 100–138
• 700–706
• 1900–1901

Where the first number is in the range 101–109, in multiples of 100, use the changed part only in the second number, and omit unnecessary zeros:

• 103–9
• 808–18
• 1007–8

Where the first number is in the range 110–199, in multiples of 100, use two or more digits in the second number, as needed:

• 435–37
• 1986–87
• 3740–75

With numbers of four digits, use all digits in the second number if three of them change:

• 1889–1915

Note the following special cases:

• 899–900 (second number is even hundred)
• 398–396 BC (all digits repeated in years BC)