3.1 Charts & Data Visualization

Charts are an important feature of Microsoft Excel that help users present numerical information visually. Instead of reviewing large amounts of data in rows and columns, charts can make comparisons, patterns, and trends easier to understand.

What You Will Learn

• Understand the purpose of charts in Excel.
• Select appropriate data for creating charts.
• Create different types of charts.
• Change chart titles and labels.
• Format chart elements.
• Understand when to use different chart types.
• Create charts for business and academic data.
• Use charts to communicate information clearly.

What is Data Visualization?

Data visualization is the process of presenting information in a visual format such as a chart or graph. Visual representations can help users identify differences, patterns, trends, and relationships within a dataset.

Why Use Charts?

Charts can make complex information easier to interpret. For example, a table containing monthly sales figures may require users to compare many numbers manually. A chart can present the same information visually, making changes between months easier to identify.

Common Chart Types

• Column Chart: Useful for comparing values across different categories.
• Bar Chart: Useful for comparing categories, especially when category names are long.
• Line Chart: Useful for showing changes and trends over time.
• Pie Chart: Useful for showing how categories contribute to a whole when there are a limited number of meaningful categories.
• Area Chart: Useful for displaying trends and changes across a continuous sequence.
• Scatter Chart: Useful for examining relationships between two numerical variables.

Creating a Chart

To create a chart, users normally select the relevant data and choose a suitable chart type from Excel’s chart tools. Excel creates the chart based on the selected information.

Chart Elements

A chart can contain several elements that help explain the displayed information.

• Chart Title: Describes what the chart represents.
• Axis: Provides reference points for the displayed values.
• Axis Titles: Explain what the axes represent.
• Legend: Identifies different data series.
• Data Labels: Display values directly on the chart.
• Gridlines: Help users compare values against the chart scale.

Choosing the Correct Chart

The chart type should match the purpose of the analysis. A column or bar chart is useful for comparing categories, while a line chart is generally useful for showing changes over time. A pie chart can be used when the main purpose is to show the parts of a meaningful whole.

Formatting Charts

Charts can be customized by changing titles, labels, legends, layouts, sizes, and other available formatting options. The goal of formatting should be to make the chart clear and easy to understand rather than unnecessarily complicated.

Practical Activity

Create a worksheet containing monthly sales data for one year.

1. Create columns for Month and Sales.
2. Enter sales information for twelve months.
3. Select the data.
4. Create a column chart showing monthly sales.
5. Add a suitable chart title.
6. Add data labels if appropriate.
7. Create a line chart using the same data.
8. Compare the two charts and identify which one communicates the monthly trend more clearly.

Advanced Practical Exercise

Create a sales report containing Product, Quantity Sold, Revenue, and Month. Create a suitable chart to compare products and another chart to show revenue over time.

Learning Outcome

After completing this section, learners will be able to create and format charts, select suitable visualization types, and use charts to present numerical information and identify basic trends and comparisons.