Feel Like a Number? Part 2. Using Numerals for Quantities Below 10
by Anne Breitenbach
When do we format a number below 10 as a numeral? In most cases, it’s when the value itself is the focus of the construction, that is, you are pointing your reader to a specific quantity measurement. Rule 4.31 breaks that down into a number of parts. We looked at Parts a and b in the last post. Here we look at Part c:
c. numbers that immediately precede a unit of measurement
a 5-mg dose
with 10.54 cm of
On the face of it, that seems clear enough to require little by way of exegesis. And, in truth, in very few cases should this rule provide a challenge. Yet even this rule can (very occasionally) cause moments of head scratching when one struggles with the issue, what is a unit of measurement?
Consider the following (and feel free to sing along): “eight bottles of beer on the wall, eight bottles of beer, take one down, pass it around . . . .” Is a bottle of beer a “unit of measurement” per the meaning of the rule? (Yes, something similar to this has actually come up in academic articles.) “Bottle” is an entry in A Dictionary of Units of Measurement, in which it is defined as “a unit of volume . . . . that varies with the nature of the contents.” In context, it seems clear that the meaning does focus on the “bottle” as a unit of measurement. So per the rule, “8 bottles” would be appropriate.
Does that mean that if you haven’t thought of a descending number of bottles of beer as units of measurement you’re incorrect? If you reason that a unit of measurement that varies by content and by context is hard to take seriously as a measurement, well, it’s a reasonable position. To reiterate a point we’ve made a number of times on the blog (e.g., The Flexibility of APA Style), although the stylistic guidelines in the Publication Manual are meant to ensure consistency, they are not meant to replace your own reasoned judgment.
For more examples of units of measurement (though by no means an exhaustive list!), please refer to the Publication Manual, Table 4.4 and the units of time that follow (p. 109).
More on Numbers to follow.