A petal chart, also known as a star chart because of its appearance, plots the values of each category along a separate axis that starts in the center of the chart and ends in the outer ring.
For practice purposes, use the following data to create a star chart with similar results. For this, you can copy this data to your worksheet, or you can use your own data.
To start with, copy the example worksheet data into a blank worksheet, or open the worksheet that contains the data that you want to plot in a petal chart.
Select the data that you want to plot in the star chart, including labels.
Inserting Petal Chart
On the Insert tab, in the Charts group, click Other Charts.
Under Radar, click Filled Radar
If you want to change the color theme of the chart, click on the chart area of the chart. This displays the Chart Tools, adding the Design, Layout, and Format tabs.
On the Design tab, in the Chart Styles group, click the chart style that you want to use.
To change the size of the chart, on the Format tab, in the Size group, select the shape size that you want in the Shape Height and Shape Width boxes, and then press ENTER.
Petal Charts are nothing but tweaked radar charts that segregate the information yet somehow provide comparability. The purpose of a radar chart is to compare m options across n parameters so that the audience can be convinced that option A is better than option B.
Yes, you are right, it is very difficult to understand these charts in one go, because the human eye is not trained to go around circles four times, stopping at a number of different parameters only to realize that all the options are equally bad (good), but still, in some scenarios petal charts are the only solution to present particular kinds of data.