11.4.3 Comparative Bar Charts

Another way of displaying the totals would be to split each bar into two, one representing the number of males and the other the number of females in each category. To enable these numbers to be compared directly, the bars representing males and females can be placed next to each other as shown below. This is an example of a comparative bar chart.

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This vertical bar chart has the same axes and source as the previous chart. However the title reads “Male and Female guests at hotel” and the key shows two categories male and female. For each category, there are two bars next to each other, the left hand bar represents the male guests and right hand bar represents the female guests. For the Irish category, the top of the left hand bar is opposite the 10 on the vertical scale and the top of the right hand bar is opposite the 7. For the British category, the top of the left hand bar is opposite the 4 on the vertical scale and the top of the right hand bar is opposite the 10. For the Mainland European category, the top of the right hand bar is opposite the 2 on the vertical scale and the top of the left hand bar is also opposite the 2. For the Rest of World category, the top of the left hand bar is opposite the 5 on the vertical scale and the top of the right hand bar is opposite the 7.

Activity: Reading a Comparative Bar Chart

Using the bar chart above, answer the following questions.

(a) How many female guests from Britain were there?

Answer

(a) There were ten female guests from Britain.

(b) How many male guests in total stayed at the hotel?

Answer

(b) The total number of male guests was .

Notice how all these charts followed the same format with the title and source clearly labeled and the axes and scales clearly marked, but they emphasized different aspects of the data. When you are displaying data in a graphical form, it is important to choose a chart or graph that stresses the main points as simply as possible, so that your reader can understand your chart quickly and easily.

The tourist market bar charts display how many items (in this case, guests) there are in each category. How many times an item occurs is known as the frequency. Charts that display frequencies are also known as frequency diagrams.

For more practice interpreting bar charts, try the following lesson:

• Bar charts and frequency diagrams [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)]