Not all data is more comprehensible when graphed, and some types of data work fine with one type of graph and don t work at all with another. For example, a pie chart is great for something like a budget, where you want to see where most of your money goes. The pie wedges provide a graphic representation of the fixed budget allocations and how the amounts in each category contribute to the total. On the other hand, if you try to create a line chart or radar plot from the same information, you ll be left confused. Line charts are great for tracking movement of figures over time, such as fluctuating stock prices.
Radar charts are useful for plotting changes in values relative to a central reference point.
Getting the scale right You need to use similar care with the scales in your graphs and charts. As with statistics, it s just as easy to make your pictures hide a thousand untruths as it is to make them paint a thousand words. Choosing a scale that s appropriate to the range of data that s to be displayed is essential if you want your charts to accurately map the underlying figures. Similarly, if you have a very wide range of values to chart, a chart makes it easy to get a graphic overview of the contrasts in those figures while at the same time obscuring the details. With experimentation and experience you ll become adept at choosing the most appropriate chart.