Spider charts are a useful tool for illustrating balance or imbalance, as well as strengths and weakness. Spider charts get their name because they resemble spiderwebs, especially when more than one set of data is being charted. Because the data spreads outward from the center, spider charts are often called radar charts, which is the name used by Microsoft Excel.
Uses of Spider Charts
Instead of plotting data from left to right or bottom to top, a spider chart plots data from the center outward. The radius of the chart represents the X-axis, while the circumference represents the Y-axis. This makes spider charts ideal for illustrating balance or imbalance in data. For example, if you rated competing athletes on a scale of one to five across several performance categories, a spider chart for each athlete could be used for quickly comparing overall strengths and shortcomings in any category.
To create a quick spider chart using Microsoft Excel Online (see Resources for link), type two columns of data into a new worksheet. For best results, use between five and ten rows. For example, populate the first column with the days of the week, and the second column with the number of calories you consumed or the number of hours of sleep you had each day. Highlight the cells containing your data, click the Insert tab, select "Other Charts" and then click any of the three "Radar" charts that appear in the drop-down menu.
Excel Radar Chart Options
Microsoft Excel Online offers three types of Radar charts. The first is a plain radar chart, resembling a spiderweb, in which the data forms a polygon. The second is a Radar chart with markers. Each data point on the polygon is marked with a dot, making this useful if you have a lot of data points so you can easily identify values. The third is a filled Radar chart. Sometimes called a petal chart, the polygon is filled with color, making its shape easily distinguishable. This can be useful if you are using the chart in a visual presentation to an audience.
Formatting an Excel Radar Chart
As with other charts, you can format an Excel radar chart with a chart title, legend, data labels, axes and notes. If you are using a filled radar chart with more than one set of data, the first polygon may be hidden by the second polygon. To prevent this, arrange your columns so that the larger units are on the left if possible. This places the larger polygon first, so the second polygon fits over it without obscuring the data behind it.