No matter how good your command of English, no matter how good you are at writing, there are times when words and figures are not enough. There are times when, to make what you want to say quite clear, you need a more visual approach. That is when tables and charts come into their own.
It is not the purpose of this book to show you how to calculate the figures, percentages, averages, etc. you may need in your documents or presentations, just to show you some of the ways in which they can be presented.
The easiest, and perhaps the most common, way to show figures is to tabulate them. How you present your tables will depend on the information you want to highlight. As an example, let us consider how you might present a comparison between two years’ sales figures, broken down into sales areas.
There are times when raw information, even in the form of a table, does not make enough of an impact. Since your aim is to make your audience’s job easier, you need a way of presenting difficult information in an easily digestible form. Sometimes that form needs to be visual, and one of the common forms of visual presentation is the graph.
Graphs are used for a variety of purposes, but the most common in business is to show a trend over time. The cost of salaries, sales figures, production costs, number of employees, goods produced and overheads are just some of the many statistics that can be plotted graphically to show the underlying trend. To illustrate this, let us assume that you are a manufacturer.
You do not have to use indexing, of course. If all the items you want to plot can be expressed in the same terms, you can plot actual values. But you need to ensure that you are comparing like with like. It would not be very helpful, for example, to plot costs and prices without indexing, even though both are monetary values. In the first place, prices are likely to be so much higher than costs that a slight fluctuation in prices will look very much bigger than a similar fluctuation in costs. In the graph below, for example, the upward trend in prices looks very much steeper than the trend in costs, because the values are so much higher.
Graphs are very good for showing trends, but not so good if you want to compare two types of data at a particular time. You can, of course, do this by comparing the points on the graph, but the comparative values are not easily apparent – and as always your aim should be to make your audience’s task easier. This is where a bar chart comes into its own. You can show a particular year’s for a number of different departments (or activities, or product lines, or countries, or anything else) and have an instant comparison. If you show the figures for more than one period, it will also show you the trend, but not as clearly as a graph.
Pie charts are a good way of showing in what proportions a total figure is split between various subdivisions. Indeed, this would be the best way of presenting them if the aim was to show how the company’s overheads were divided between the three departments. But it is not a good way of making comparisons between one set of figures and another. The pie chart shows more clearly than the bar chart what share of the company’s total overheads is allocated to each department, but it is not so easy to see that the Sales Department’s overheads are one and half times those of Distribution.
Flow charts are not used to present figures, but rather to show the flow of work or activity diagrammatically. As always, the aim is to make it easier for your audience to understand what you are saying, and very often a flow chart does this better than a verbal description. Below is a simple flow chart for an office dealing with customer enquiries and using standard letters. As you can see, by following the arrows and instructions it is easy to see what needs to be done at each stage.