Bar and Bar Combo Charts

Overview

The primary use of a bar chart is to show comparisons between time periods or categories. One axis shows items to compare while the other displays the value being measured; the longer the bar the greater its value. The primary goal of a bar chart is to showcase the relationship between the two axes. A grouped bar chart visualization is displayed if the data set has multiple data series within it.

Combo options:  The bar-line combo chart type allows you to show one or more data series as lines. You can use this type for mean values, median values, etc.  (See example bar-line combo.)  The bar-pie combo shows both a bar chart and a pie chart of the same data. Hovering over one chart filters the other.  For example, hovering over a bar in the bar chart filters the pie data to that point in the timeline.  (See example bar-pie combo.)

Chart is an interactive content type in the WCMS.  Go to examples at the bottom of this page to try out “live” charts.

Legend

Interacting with the labels in the legend will highlight or isolate the selected data series. Each data series can be toggled on and off individually, allowing users to view a wide variety of combinations.

Table

Sorting:  Selecting the top row of a column sorts the entire table by the content within the selected column. Selecting the same column multiple times rotates the sorting feature between three states: Descending, Ascending and Off. Only a single column can be sorted at one time.

Source:  When referencing information from outside of the current page, you should provide a source link. Source links should be short and descriptive; they should not be the full URL. Source links are always displayed directly above the table.

Usage

Other Guidance

• Chart Title:  Good titles are invaluable. Your chart title should be long enough so that your audience can make sense of the chart. A glance at the title should clearly convey what the chart contains. A good title requires a balance between a short title and one with enough descriptive information to describe the chart clearly.
• Number of Series Bars:  Too many series bars result in visual clutter and make the chart difficult to interpret. One to four bars with a maximum of six bars is recommended. The Chart Builder supports up to nine different colored bars in a bar chart. However, if you have more than six sets of quantitative values, consider breaking them into multiple charts.
• Grid Lines:  In most cases, both horizontal and vertical grid lines should be hidden to reduce chart clutter. Approximate values can be perceived without grid lines.  When the difference in data values is close, horizontal grid lines can be shown to better support data value comparison.
• Data Source:  The data source makes your graphic more reputable. It also allows those who are interested to dig deeper.
• Outliers in Series Bar Data:  If the data set includes one or more extreme outliers, the visualization can be difficult to process. If the variation can be seen only on a single bar and the rest are flat, do one of the following: Modify the data set to remove / adjust the outlier issue, split the chart into multiple charts, or select a different chart type.
• Confidence Intervals: Confidence intervals give an indication of the certainty of the dataset. In the Data Import Wizard, you can configure the chart to show confidence intervals in the chart visualization. See chart example.
• Filtering: Filtering options can be set in the Data Import Wizard.  To create a filter, select a data column that describes a variable (gender, age group, etc.) and provide a label. This creates a drop-down menu with the possible options for the specified data column. When a site visitor changes the drop-down selection, the chart and data are refreshed to show only the rows of data for the selected label.  Note that filters can be applied only to a “Columns and Rows combined” data set, the second option in the data-import screen capture below.  See chart example.
• Social Media Sharing:  The Chart Configuration tool allows you to specify a URL, title, and description for social media posts.  It also supports display of the chart embed code for copying.

Chart Color Palettes

Standard Categorical (Non-Time-Based) Bar Chart

With WCMS release 4.8.2, the bar chart now supports non-time-based data, as illustrated below. See example data file excel icon[XLS – 97 B].

Stacked Bar Chart

To create a chart like the one below, select “Bar Chart” as the type and then select the option “Stack Bars.”  Stacked bars can work well to show percentages when every bar totals 100.

Combo Bar-Pie Chart

To create a chart like the one below, select Combo Bar-Pie as the chart type.  See example data file excel icon[XLS – 335 B].

Bar with CIs in Visualization

If you have high and low CI columns  in your source data, you can easily specify that CIs display in the visualization area.  During data configuration, select the high and low columns in the “Confidence Intervals” section. See example data file excel icon[XLS – 189 B].