15 Lists and tables
15.2.1 General principles
A table is a set of data systematically displayed in rows and columns. Tables are best used for information that is too complex to be presented clearly in a list or in running text, and particularly for information intended for comparison, either within a single table or between similar tables.
Tables should be numbered by chapter or section in the order in which each is mentioned (Table 1.1, Table 1.2, etc.) If there are only a few tables they may be numbered in a single sequence throughout the text. Frequent or large tables may be better placed at the end of the chapter or as an appendix to text; tables in an appendix are numbered separately. Unlike lists, tables should not be broken across pages unless their size makes a break unavoidable.
Consider whether tabular presentation is the clearest means of setting out the material. It might be more digestibly presented in a few sentences, or as a figure or graph. Two or more tables might be better merged, or a large one split up. For example, large tables viewed on a small screen can be problematic as they can be unreadable if zoomed out to show the whole structure or hard to interpret if column and row headings are not visible at larger font settings; careful consideration should be given as to whether to split the table into smaller components, for example, or to display the data in a different way.
The information must be relevant to the textual argument and correspond to what the text describes. It should not merely repeat the text. The order of elements in the table should be transparent; if no other order can be imposed on the table as a whole, alphabetical or numerical order may be best.
Omit vertical rules in tables—presentation is clearer and less cluttered without them. Horizontal rules should be kept to a minimum, although head and tail rules are included in most cases.
Most word-processing programs have a tool to create and edit tables; most page layout software can import the result but success depends partly on how well the table has been prepared. In the table body remove unnecessary spaces and tabs, and avoid adding a new line with a hard return—introduce an extra row instead. (A swift way of cleaning up a badly prepared table is to copy it into a blank spreadsheet then back into the document.) Alternatively, present data as columns separated by single tabs, rather than in table cells; include a tab for every column including empty cells. Do not use multiple tabs or spaces between columns. For either method preferably apply word-processor styles to the different table elements: title, column headings, body other than final row, final row, and notes.
Tables can also be prepared efficiently as spreadsheets but authors and editors should be aware that cell formulas will not import into other types of software, only the result of the formula; this is not a problem provided the table is not pasted back into the spreadsheet, e.g. for amendment. Most spreadsheet file formats can be imported into page layout software; however, spreadsheets should not be embedded in word-processed documents but presented separately.
Be prepared for the fact that badly prepared tables may be rekeyed if quicker than tidying up after an unsuccessful import. It is helpful if hard copy or a PDF that shows intended layout accompanies the files, in case vertical alignment is lost. Drawn elements within a table, such as chemical structures, may need to be treated as artwork. When in doubt, flag problematic tables or seek advice from the publisher.
Page layout software treats tables as separate elements, which are positioned once the text has flowed into the page template; consequently it may be more convenient if tables are presented separately rather than in situ in the document—it is worth checking whether your designer or publisher has a preference. If no guidance is given, gather the tables together in one place, or group them by chapter for example, or present them in sequence at the end of the document if only a few. The approximate position of tables should be clearly flagged—by a placement indication in the margin of hard copy or on a separate line in an electronic text, for example:
All tables should also be cited by number in the text. Citations can be of the style Table 2.1 summarizes the planning processes, or in the passive form The planning processes are summarized (Table 2.1) … Avoid positional references such as ‘the table above’ or ‘the following table’, as the final paginated layout is likely to be different from that in the script.
Running heads can be set normally over full-page portrait (upright) or landscape (turned or broadside) tables, or they can be omitted; consistency is important.
If the author-number reference system is used in the text (
15.2.2 Table headings
Tables must have headings, which are usually positioned above the table, consisting of the table number and a title that describes what the table contains. The title may use minimal or maximal capitalization according to the style of the work as a whole; no full point is needed after the table number or at the end of the heading.
When units are the same throughout the table they may be defined in the heading, for example:
The heading may also be used to expose the logic behind the order in which the material is presented in the table, for example:
15.2.3 Column and row headings
The length of column and row headings should be reduced to a minimum, so any repeated information should be removed to the table heading. Similar tables should be treated similarly. Capitalize only the first word and proper names in each heading; do not include end punctuation. Do not number headings unless the numbers are referred to in the text. Spans in headings must not overlap: 1920–9, 1930–9, 1940–9 rather than 1920–30, 1930–40, 1940–50.
Units, where needed, are usually in parentheses, and should not be repeated in the body.
Column headings with common elements can be combined over a ‘straddle’ or ‘spanner’ rule (see
Totals may be set off by a space or a rule (see
Row headings (also called stub or side headings) may or may not have a heading like other columns. If they do have a heading, ensure that it is appropriate and relevant to all of the stubs. Where row headings turn over to another line, data should be aligned consistently with either the last or the first line of the side heading.
15.2.4 Body of table
The body of a table is simply the tabular data introduced and ordered by the columns and stub. Where data drawn from a variety of sources has to be recast to allow comparison, ensure that this does not introduce inaccuracy or anachronism, or distort the material’s integrity, especially if the source is in copyright.
The unit(s) used in the table should suit the information: for example, national agricultural production figures may be easier to compare if rounded to 1,000 tons. Rounding also saves space, but editors should not make wholesale changes without querying them with the author. Tables intended for comparison should ideally present their data consistently in similar units. Ensure that abbreviations are consistently applied from one table to another, and that all units and percentages are defined. Exclude end punctuation. Mathematical operators (+, –, >, etc.) may be close up to surrounding digits to save space if necessary. Ensure that the correct symbols are used for minus signs, hyphens, and en and em rules; on hard copy mark their first occurrence in each table. Add zeros in front of decimal points if omitted; the exception may be probability values, for example p < .05, as house styles vary.
Familiar abbreviations are acceptable, such as %, &, country abbreviations, and those well known in the reader’s discipline. Ambiguous abbreviations such as n/a (‘not applicable’ or ‘not available’) and unfamiliar abbreviations must be explained in the notes (see
Turn-lines in simple items in columns are indented 1 em, with no extra vertical space between items (see for example column 2 in
Related figures in a single column should have the same number of decimal places. Unrelated figures may have a different number of decimal places, but only if reflecting different levels of accuracy. Editors should check with the author before rounding them to a common level. Percentage totals may vary slightly above or below 100 per cent as a result of rounding.
When statistical matter within each column is unrelated, align it on the left with the column heading (see
When statistical matter within the columns is related, align it so that the longest item aligns with the column heading and other items align with the decimal point or with the final digit on the right (see
15.2.5 Notes to tables
Notes fall directly beneath the table to which they refer; they are not incorporated with the text’s footnote system. Set notes to table width, normally one size down from table size. General notes, notes on specific parts of the table, and probability values should appear in this order; source notes may go first or last provided they are treated consistently. Ensure that notes to a table cannot be mistaken for text recommencing after the table. General and source notes are uncued and often preceded by Note: and Source: respectively. The reference structure of source notes matches that used elsewhere in the work. Each note should generally begin on a new line and end with a full point (see
Mark specific notes with a system of indices different from that used in the text (for example * † §), as in
Probability values may be indicated by a system of asterisks, in which case the convention should be explained in a note: ‘*p < .05; **p < .01; ***p < .001’. Editors should not impose other symbols in this case.
15.2.6 Presentation on the page
Tables may be placed on the page in portrait or landscape format. Authors are not responsible for determining the format in which tables will be set. A wide table may fit a page’s measure if the arrangement of column and stub heads is reversed, but editors should consult the author first. Do not rearrange similar or related tables into differing structures.
Large portrait and landscape tables may be presented over two or more pages of text. Hard-copy editors should indicate preferred places where a large table may be split; on-screen editors can do the same on a PDF or in a note to the designer. Headings do not need to be repeated where continued tables can be read across or down a facing page. If the table continues on a verso page, however, indicate which headings need to be repeated. On-screen editors should not repeat headings in files that will be imported into page-layout software as that will be done automatically.
In page proofs insert a ‘continued’ line, such as ‘Table 2 cont.’, only if the table turns over to a verso page, not if it extends over facing pages. When several continued tables are given in succession, a short form of each table’s title can be helpful.