Can You Describe A Pie Chart?

           A chart represented by a circle divided into a number of parts is called the pie chart. Each part is called a sector. A sector represents the size or frequency of a particular thing in relation to the total. In a pie chart, the central angle (also the area) is in proportion to the quantity it stands for. All the sectors combine to make a complete circle. There is a pie chart display where one of more sectors is separated from the complete circle. This display is called the exploded pie chart.

           The pie chart is the most widely used graphic tool to represent the statistical data in the business community and print and television media. It is however not widely used to denote scientific or technical data.  It most popular criticism is the difficulty to compare data across different pie charts.

           Pie charts make a good representation of data when the categories illustration a proportion of the total. They are most effective in displaying data that could be rounded off. For example they are effective when the data divides the slices into 20% or 40% etc.  Each sector of the pie chart is usually represented by a different color.

A pie chart or a circular graph is used for the comparison of values of different items by making the sectors of a circle. To make a pie diagram or a pie chart, first draw a circle of suitable size. We use the fact that the total area corresponds to the total number of degrees in the circle consisting 360 degree. Now find the angle in the circle by dividing each individual figure by the total figure and multiply it by 360. Having the figures of the various angles thus calculated, divide the circle into different sectors using a protractor. Finally, represent the different sectors by colours or lines to make it attractive.