A pie shows how a whole splits into a few parts. In Tableau you build one on the Marks card, not on the shelves:
- Set the mark type to Pie. A new Angle button appears.
- Drop the dimension that names the slices on Color.
- Drop the measure on Angle. Each slice gets an angle in proportion to its value.
Put the dimension (and the measure, if you like) on Label to print them on the slices.
A common slip is to drop the measure on Size instead of Angle. Size makes the whole pie bigger or smaller; it doesn't change the slices, so every slice looks the same.
Pies work for two to five parts. With more slices, angles are hard to compare, and sorted bars tell the story better.