Template:Grammar and Style/Numbers and Units
Numbers and Units
Numbers and Units
Introduction
As science communicators, you will often have to include highly specific information in your written materials. For example, you might be writing a lab report in which you provide numerical details about the method you used in your experiment. There are some rules to follow if you want to do this effectively and achieve your basic goal of enhancing the readability of your work.
In a few cases, you might have to make a judgment call as to which rule should be followed; when working with numbers especially, there are sometimes occasions when rules from different style guides clash. Having said this, if you plan your work with clarity in mind, most sentences can be simplified to follow the important, universally accepted rules. When this is not possible, you should follow the one golden rule: Always be consistent in your style.
Some Basic Rules for Working with Numbers
| Rule | Example |
|---|---|
| 1. Spell out small numbers (one to nine). | 1. I performed three experiments yesterday. |
| 2. Use numerals for larger numbers (10 +),except when beginning a sentence. | 2. Mike performed 12 experiments.
Fifteen days later, he collected the data. |
| 3. Use numerals for counts, percentages, decimals, magnifications, and official scales. | 3. We found 8 mice, 12 rats, and 37 rabbits. Mammal populations here have grown by about 30% in the last five years. |
| 4. Use commas to make large numbers easier to interpret (one comma separates each three figures),
but round numbers up/down when very large and use a combination of numerals and words. |
4. There are 5,194 new species of insect discovered each year.
There are approximately 7.5 million insect species on Earth. |
| 5. Avoid having two distinct numbers written next to one another, most simply by rearranging a sentence. | 5. We tested 15 different 19-year-olds [not ‘we tested 15 19-year-olds]. |
| 6. Spell out names and nouns. | 6. The First Law of Thermodynamics. |
| 7. Use numerals for dates. | 7. On March 4 [or 4th], we have an exam. |
| 8. Use numerals for times,
except when writing ‘o’clock’ |
8. The exam begins at 9:00 am,
and finishes at one o’clock in the afternoon. |
| 9. Use numerals for currency references. | 9. My lunch cost $4.35, but the chips were only 85 cents. |
Always remember the one golden rule of being consistent in your style. If two rules clash in one sentence, you will have to favour one over the other. Make sure you continue to favour that one over the other throughout your text.
Some Basic Rules for Working with Units
| Rule | Example |
|---|---|
| 1. Spell out small numbers (one to nine). | 1. I performed three experiments yesterday. |
| 2. Use numerals for larger numbers (10 +),
except when beginning a sentence. |
2. Mike performed 12 experiments.
Fifteen days later, he collected the data. |
| 3. Use numerals for counts, percentages, decimals, magnifications, and official scales. | 3. We found 8 mice, 12 rats, and 37 rabbits. Mammal populations here have grown by about 30% in the last five years. |
| 4. Use commas to make large numbers easier to interpret (one comma separates each three figures),
but round numbers up/down when very large and use a combination of numerals and words. |
4. There are 5,194 new species of insect discovered each year.
There are approximately 7.5 million insect species on Earth. |
| 5. Avoid having two distinct numbers written next to one another, most simply by rearranging a sentence. | 5. We tested 15 different 19-year-olds [not ‘we tested 15 19-year-olds]. |
| 6. Spell out names and nouns. | 6. The First Law of Thermodynamics. |
| 7. Use numerals for dates. | 7. On March 4 [or 4th], we have an exam. |
| 8. Use numerals for times,
except when writing ‘o’clock’ |
8. The exam begins at 9:00 am,
and finishes at one o’clock in the afternoon. |
| 9. Use numerals for currency references. | 9. My lunch cost $4.35, but the chips were only 85 cents. |
Video Resource
For a recap and for some extra information about writing succinctly and dealing with jargon, please watch Grammar Squirrel’s video on the UBC Science Writing YouTube channel.
We then suggest you complete the quick quiz (below) to see whether you have mastered some of the important skills relating to succinct writing and dealing with jargon.
Numbers and Units Quick Quiz
Quick Quiz Answer Key
To check your answers and see whether you are now a wizard at writing succinctly and dealing with jargon, access the answer key here.