In this section you have been introduced to some guidelines for presenting data in tables. These guidelines apply particularly when the data in a table are being used to illustrate a particular point or to show up clearly a particular pattern.
You have seen that, in some circumstances, following the second of these guidelines leads to some pooling together of rows. (In other cases, it could be columns or individual cells that are pooled.) However, care is needed when, by making such simplifications, information is lost from the table. The examples of the application of guideline 4 that you have seen involve calculating appropriate ratios or rates. Such calculations are very common in dealing with data in tabular form.