Chapter 2: Using Excel
Noreen Brown; Barbara Lave; Julie Romey; Mary Schatz; Diane Shingledecker; and Gail Poitrast
LEARNING OBJECTIVES
- Construct a line chart to show a time series trend.
- Learn how to adjust the Y axis scale.
- Learn how to use a column chart to show a frequency distribution.
- Learn how to use a pie chart to show the percent of total for a data set.
- Construct a stacked column chart to show how a percent of total changes over time.
- Construct a histogram when given quantitative data.
This section reviews the most commonly used Excel chart types. To demonstrate the variety of chart types available in Excel, it is necessary to use a variety of data sets. This is necessary not only to demonstrate the construction of charts but also to explain how to choose the right type of chart given your data and the idea you intend to communicate.
Choosing a Chart Type
Before we begin, let’s review a few key points you need to consider before creating any chart in Excel.
- The first is identifying your idea or message. It is important to keep in mind that the primary purpose of a chart is to present quantitative information to an audience. Therefore, you must first decide what message or idea you wish to present. This is critical in helping you select specific data from a worksheet that will be used in a chart. Throughout this chapter, we will reinforce the intended message first before creating each chart.
- The second key point is selecting the right chart type. The chart type you select will depend on the data you have and the message you intend to communicate. If you are using categorical (sometimes referred to as qualitative data), a bar chart or pie chart is appropriate. If you are using quantitative data, then a histogram or line chart is appropriate.
- The third key point is identifying the values that should appear on the X and Y axes. One of the ways to identify which values belong on the X and Y axes is to sketch the chart on paper first. If you can visualize what your chart is supposed to look like, you will have an easier time selecting information correctly and using Excel to construct an effective chart that accurately communicates your message. Table 4.1 “Key Steps Before Constructing an Excel Chart” provides a brief summary of these points.
Integrity Check
Carefully Select Data When Creating a Chart
Just because you have data in a worksheet does not mean it must all be placed onto a chart. When creating a chart, it is common for only specific data points to be used. To determine what data should be used when creating a chart, you must first identify the message or idea that you want to communicate to an audience.
Table 4.1 Key Steps before Constructing an Excel Chart
| Step | Description |
| Define your message. | Identify the main idea you are trying to communicate to an audience. If there is no main point or important message that can be revealed by a chart, you might want to question the necessity of creating a chart.