Illustrator has easy to use tools to make simple shapes into precise drawings including built-in math to divide shapes into concentric copies. The text entered in the Rotate dialog box was 360 / 12 and that translates to 360 degrees evenly divided into 12 separate shapes with a result of 30 degrees each. Press the copy button and your shapes is copied and moved 30 degrees. Press Cmd+D (Mac) Ctrl+D (Win) 11 times and you’ve copied full circle.
That’s just one of many cool things about Illustrator.
Or you can “cheat” and just download the chart here:
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