Learn about the **polar area diagram** with these printable diagrams. Example of a polar-area diagram was invented by Florence Nightingale. The original diagram like we posted right below was in color with the outer area in blue, the central darker areas in black, and the central lighter areas in red.

The Areas of the blue, red, & black wedges in the *polar area diagram* above are each measured from the center as the common vertex. The blue wedges measured from the centre of the circle represent area for area the deaths from Preventable or Mitigable Zymotic diseases, the red wedges measured from the center the deaths from wounds, & the black wedges measured from the center the deaths from all other causes.

Nightingale’s graph above is like a pie chart, cut into twelve equal angles. The Polar Area chart is similar to a usual pie chart, except sectors are equal angles and differ rather in how far each sector extends from the center of the circle. The polar area diagram is used to plot cyclic phenomena (e.g., counts of deaths by month).

Some of these diagrams are similar to a pie chart, but with constant angles, varying area proportional to data. Use these diagrams to study about the polar are and make sure to get more and more printable educational diagrams by frequently visiting our site!