Lollipop Chart

When choosing a chart type for data visualization, it's essential to consider the type of data being presented and the intended audience. A lollipop chart is worth considering for many scenarios.

What exactly is a lollipop chart?

A lollipop chart is a more visually appealing variation of a bar chart. The bar is replaced with a thin line and a circle at the end of it, making it resemble a lollipop. In this composite type of chart, the line length represents the data's magnitude, while a dot at the end of the line marks the exact value. It mainly compares categorical data and shows rankings or trends over time. Because it combines multiple visual elements, the lollipop chart can effectively convey complex information more engagingly.

Lollipop Charts vs. Bar Charts

Lollipop charts use the same value encoding method as bar charts. Following are the pros and cons of lollipop charts.

Pros

• An excellent alternative to bar graphs, especially when dealing with extensive datasets with high values.

• They are preferred over traditional bar charts because they are visually appealing and less cluttered.

• Its vertical lines and circle markers help viewers quickly identify essential data points.

• They are used to display many data points in a compact and organized manner.

• Effectively show changes over time using time as the categorical variable and numerical values as magnitudes.

• Helpful in visualizing trends or patterns in data.

• Circles can be customized with different shapes or icons of specific categories to display category information more intuitively -something not possible with bar charts.

Cons

• Challenging to precisely locate the data point compared to a bar chart's straight edge. The center of the circular marker at the end of the thin bar represents the value, making it difficult to see where it falls on the scale.

• The circular markers may extend beyond their actual value, leading to inaccuracies, particularly with small datasets or subtle differences between data points.

• Challenging to make precise comparisons, mainly when the circle size is large or uneven.

Lollipop vs. scatterplot

Overall, the lollipop chart combines elements of both bar charts and scatterplots. The foundation of the lollipop chart is a scatterplot, which necessitates both x and y values. The x values represent the actual data points, whereas the y values are fabricated and inserted to ensure that each lollipop is equally spaced. Furthermore, lollipop charts can also effectively display the relationship between two variables. For example, a lollipop chart can show the correlation between the price of a product and the number of units sold. By placing the price on the x-axis and the number of units sold on the y-axis, a lollipop chart can quickly show if there is a positive or negative correlation between the two variables.

Use Case 1: Basic Lollipop Chart

Objective

To create a lollipop chart to analyze the "Sub-Category" wise sales percentage and see how it can enhance a bar graph's visual appeal.

Steps

First, we will create a simple dual-axis bar chart. Then merge the two separate bar charts into one. Finally, format the chart to resemble a lollipop.

Data source

Sample Superstore

Follow the step-by-step method to create a basic lollipop chart

Step 1: Connect to the data source

Step 2: Go to a new sheet and drag “Sub-Category” to the Rows and “Sales” to the Columns

Step 3: Create a dual bar chart – Drag the “Sales” to the Columns field next to the aggregated field SUM(Sales)

Step 4: Choose the first bar chart into a “Bar” from the Marks card

Step 5: Change the second bar chart into a “Circle” from the Marks card

Step 6: Right-click the second axis and select the “Dual Axis”

Step 7: Right-click the top axis and select the “Synchronize axis, “ and uncheck the "Show Header" to remove the top header

Step 8: Adjust the size of the two bar charts to make them look like a lollipop.

Reduce the size of the bar from the first bar chart

Step 9: Increase the size of the circle from the second bar chart

Step 10: Drag the “Category” to the Color in the Marks card for the bars

We have the lollipop chart ready

Swap the rows and columns for a vertical lollipop chart

Optionally, sort it in descending order and insert the sales percentages in the circles for more clarity

Use Case 2: Diverging Lollipop Chart

This variation of the lollipop chart emphasizes the directionality of your data. A visual flow can be created using these types of charts.

Objective

To create a diverging lollipop chart to analyze the "Sub-Category" wise profit percentage of the Superstore.

Data source

Sample Superstore

Step-by-step method

Step 1: Drag “Sub-Category “ to the "Columns" and add two instances of Profit to the "Rows"

Step 2: From the second chart, click on the "Dual Axis" and also make sure to check the "Synchronize Axis"

Step 3: Click on the first instance of Profit and select "Bar" from the Marks card

Step 4: We will add dynamic arrow shapes instead of circles for the second graph. For that, we need to create a calculated field, "Arrow Shape"

Formula:

IF SUM([Profit]) > 0 THEN “Positive”

ELSEIF SUM([Profit]) < 0 THEN “Negative”

ELSEIF SUM([Profit]) = 0 THEN “Zero”

END

Step 5: Click on the second instance of Profit, and from the marks card, select "Shape"

Step 6: Drag the calculated field "Arrow Shape" onto the "Shape" in the marks card.

Step 7:Click on "Shape" from the drop-down menu, select the “Filled” option

Step 8: Assign the upward arrow for “Positive” and the down arrow for “Negative

Step 9: Reduce the size of the bar from the first instance of profit and sort in the descending order

Step 10: Click the "All instance" in the marks card, and drag Profit onto the "Color"

This is the outcome.

Conclusion

Lollipop charts are a great way to spruce up the regular bar chart in Tableau while effectively communicating information. With its ability to highlight the directional aspect of data and its explicit depiction of magnitude, the lollipop chart can aid in making basic comparisons and identifying trends. Using diverging colors and growth directions also adds to its effectiveness in distinguishing between positive and negative values. Overall, it is exciting to elevate our visualizations with these charts!