Bar Chart

A bar chart is a specific type of chart that visually represents data as a series of horizontal bars, with the Y axis representing the categories contained in the data and the X axis representing the frequency. It is different from a column chart in that column charts display the data vertically.

Bar charts are most often used for categorical data that is, by definition, not dynamic in nature. For example, if one were interested in an examination of sales figures by brand before and after a marketing campaign, a bar chart would be the appropriate way to illustrate such information, as shown in the following example. First, here are the data.

	Brand X	Brand Y
Before	56.3	76.8
After	97.4	87.5
Note: Figures represent sales in millions of dollars.

A bar chart is relatively simple to construct manually. Following these steps and using graph paper is the easiest way to be accurate.

1.
Group the data as shown in the above example.
2.
Define the Y axis as “Brand.”
3.
Indicate on the X axis the scale that is to be used, which in this case is millions of dollars, ranging from 55 to 100.
4.
Draw each bar for each brand to correspond with the data, making sure that the bars are appropriately colored or patterned so they are easily distinguishable from one another.

Using Excel, the process is much simpler.

1.
Create the data on a new worksheet and save it.
2.
Using the mouse, select all the data, including the column and row headings.
3.
Click on the Chart Wizard icon on the Excel toolbar.
4.
Click Finish in the dialog box.

While the finished bar chart may not appear as attractive as you might like, modifications are relatively easy to make, as shown in Figure 1.

The following changes were made:

• Major gridlines were removed.
• All coloring was deleted except for the gray added to one of each pair of bars to help distinguish it from the other.
• Value labels were added at the end of each bar.
• A title was added, as were labels for each axis.
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• The X axis minimum and maximum were changed from Excel's default values to 50 and 105.
• The border was removed from the legend.