Creating Tables

A table is a set of intersecting columns and rows showing data according to well-defined categories. The purpose of a table is to reveal relationships within the data.

Below are some guidelines on creating tables. The focus here is on organizing the content rather than the graphic design (colours, lines, spacing, etc.). These guidelines are for numerical data, but many of the same principles apply to tables containing text or text and numbers combined.

As with most kinds of communication, form follows function: how you organize the table depends on the purpose and meaning of the content.

The Big Picture

  • Use a table when you need to present precise data to make your point. If a general trend is all that you need to show, use a line graph; to show broad comparisons in data that varies greatly, use a bar chart.
  • Experiment with different categorizations to come up with the structure that best brings out the connections among the data points. Look for themes and patterns, and consider how these can be represented in a table’s two dimensions.
  • Keep in mind your purpose as the writer: What point are you trying to make? What should the reader learn from the table?

Arranging Columns and Rows

Once you’ve decided on the categories, there are a few conventions to setting up the table:

  • The points of comparison are placed in the column heads, and the items being compared are placed in the stub entries. For statistical cross-tabulations, the independent variables are the column heads, and the dependent variables are the stub entries.
  • Put the columns in a logical order, such as left to right chronologically or in decreasing order of importance. Use alphabetical order if no other sequence emerges from the data.
  • Group similar or related stub entries together; don’t list them randomly or even alphabetically if there’s a more meaningful way of arranging them. Consider grouping rows with subentries under stub entries.
  • If you don’t group the stub entries, sort them so that the values in the most important column range from highest at the top to lowest at the bottom. The columns could also be sequenced with high to low values left to right—overall, the values will descend diagonally from top left to bottom right.
  • There may be conventions that govern how tables are presented in your subject area. Look for examples from reputable, well-written sources to guide you. For instance, in the sample table above, the provinces are listed west to east, as is commonly done in geography.

The Data

  • Include totals, averages, or percentages only if these are meaningful and useful to your purpose.
  • Round off numbers to make them easy to read and compare, but not so much that their significance is lost.
  • Keep the number of significant digits and decimal places consistent in each cell, except for occasional outlier values (as in the Ontario and Quebec rows in the table above).
  • Use footnotes to briefly explain terminology, discrepancies, and special cases (for example, to note where data was drawn from an unusually small sample).

Title and Headings

  • Number the tables if your document has more than one. Make sure the numbering corresponds to the order in which they are mentioned in the text.
  • Give each table a title. It should precisely and concisely describe what the table shows. Don’t interpret the data in the title; do this in the main text or in a caption.
  • Keep column headings and stub entries brief but descriptive.
  • Use a spanner heading if you find that the same information is repeated in several column headings. This can also help in making the table more organized.
  • Don’t use more than two spanner headings—too many layers of headings make the table harder to read.

Stylistic Polish: Sentence Rhythm

Good writing is not only grammatical and clear; each sentence has a lively rhythm that draws readers along and keeps them interested.

We saw in a previous post how to fix a common problem of parallelism in a series. The original, incorrect sentence was

Thyme is low growing, fragrant, and has small purple-pink flowers.

This mistake can be fixed in several ways. First, we can keep the series by using a linking verb (is or has) for each item.

Thyme is low growing, is fragrant, and has small purple-pink flowers.

The sentence is now grammatically correct but awkward and wordy; because is conveys little meaning of its own, its overuse leads to weak, dull writing. Here, it only connects the adjectives (low growing, fragrant) to the noun (thyme).

We can try recasting the sentence without a parallel series.

Thyme is low growing and fragrant, and it has small purple-pink flowers.

A bit better—but now we have a clunky compound sentence without the flow and rhythm intended in the original. We can restore a graceful rhythm by making the adjectives directly modify the noun in an appositive phrase.

Thyme, low growing and fragrant, has small purple-pink flowers.

Even better is a more active verb (bears) and more information to round off and balance the sentence.

Thyme, low growing and fragrant, bears small purple-pink flowers in summer.

Punctuation Quick Tips: The Semicolon

 

The semicolon (;) is to many writers a mysterious squiggle. Some avoid it entirely for fear of using it incorrectly, while others tentatively try it out without really understanding its purpose. Writers and editors talking about the semicolon use words like rhythmic, elegant, lyrical, and subtle. It’s powerful punctuation, to be sure, but what’s it for?

Some of the confusion about the semicolon arises from its form: Is it a kind of comma? A variation on the colon? Despite its appearance, it’s neither of these. Functionally, the semicolon is most closely related to the period. It creates a pause, but not a full stop, between independent clauses (complete sentences). Editor Merrill Perlman says using a semicolon is “like rolling through a stop sign, where you are aware of slowing, but are still moving forward.”

Use a semicolon to show a close connection between ideas:

A carbon tax can be revenue neutral. It can be offset by cuts in personal income taxes.

A carbon tax can be revenue neutral; it can be offset by cuts in personal income taxes.

The semicolon creates a smoother flow, and the repetition (can be) becomes rhythmic rather than wooden.

Unlike the comma, the semicolon isn’t followed by a conjunction (and, or, but, for, nor, yet, so).

A semicolon can emphasize a rhetorical pattern used to develop an argument or make a point; it can show cause and effect, comparison, contrast, or other patterns. I like to use a semicolon as the pivot point or fulcrum of the argument: there’s balance but also movement, tension and resolution, a turning point, and sometimes a surprise.

With increasing industrialization, carbon and other greenhouse gases have accumulated in the atmosphere; the earth is warming rapidly.

The externalized costs of air pollution often turn up in increased health-care expenditures; those of climate change may be seen in billions spent on disaster recovery.

Most of us are aware of the environmental benefits of energy-efficient buildings; less well known are their social benefits.

Use transitional phrases if needed to make the pattern clear:

Relatively few highways in Canada require tolls; as a result, commuters have little incentive to take regional transit.

Changes in climate will shift agricultural zones northward; similarly, animals may migrate northward or to higher elevations.

There are limits to what can be achieved through regulation; carbon pricing, however, is the surest means of reducing emissions.

In a long complex sentence bursting with subordinate clauses and prepositional phrases, a semicolon can help the reader catch a quick rest and reorient themselves before moving on. Essayist Lewis Thomas likens the semicolon to a bench part way up a steep path:

Although the science of anthropogenic climate change is well established and the predicted effects are beginning to be observed, there are those, who, usually for ideological reasons, do not accept its premises and dispute its findings; perhaps more than anything else, this relatively small but powerful faction has prevented real progress in cutting GHG emissions.

Semicolons are also used to separate list items that contain commas:

Carbon sequestration can happen through natural biological, chemical, or physical processes;  agricultural practices that return carbon to the soil; and chemical technologies that capture carbon from the atmosphere and store it indefinitely.

Take note, however, of a caution from the style guide of The Economist regarding semicolons: “Don’t overdo them.”