# Percentage Component Bar Chart

A sub-divided bar chart may be drawn on a percentage basis. To draw a sub-divided bar chart on a percentage basis, we express each component as the percentage of its respective total. In drawing a percentage bar chart, bars of length equal to 100 for each class are drawn in the first step and sub-divided into the proportion of the percentage of their component in the second step. The diagram so obtained is called a percentage component bar chart or percentage stacked bar chart. This type of chart is useful to make comparisons in components holding the difference of total constants.

Example:

The table below shows the quantity in hundred kgs of wheat, barley and oats produced in a certain form during the years 1991 to 1994.

 Years Wheat Barley Oats 1991 34 18 27 1992 43 14 24 1993 43 16 27 1994 45 13 34

Construct a percentage component bar chart to illustrate this data.

Solution:

The necessary computations for the construction of a percentage bar chart given below:

 Item 1991 1992 1993 1994 % Cum% % Cum% % Cum% % Cum% Wheat 43.0 43.0 53.1 53.1 50.0 50.0 48.9 48.9 Barley 22.8 65.8 17.3 70.4 18.6 68.6 14.1 63.0 Oats 34.2 100 29.6 100 31.4 100 37.0 100 Total 100 100 100 100

• % indicates the percentage of each item
• Cum% indicates the cumulative percentage