Sankey charts are a visually stunning and informative way of representing data flows, making it an essential tool for anyone who wants to convey complex information in an engaging and understandable manner. This article dives into the creation and applications of Sankey charts, including practical examples and tips to make the most of this powerful data visualization tool.

What Are Sankey Charts?

Sankey charts, named after 19th-century engineer Matthew Henry Phineas Riall Sankey, display quantities of flow, emphasizing the magnitude by the width of the arrows. They are ideal for visualizing the distribution and transformations of a quantity through a system or process, such as energy consumption or financial transactions.

Creation of Sankey Charts

Step 1: Data Collection

The first step in creating a Sankey chart is collecting the necessary data. This data should include:

• Sources: The starting points of the data flow.
• Destination: The end points or recipients.
• Flow: The amount or quantity of data transferred between sources and destinations.

For example, in a financial context, sources could be income categories, and destinations could be expenses categories. The flow would be the amount of money.

Step 2: Data Preparation

Organize the data into a format suitable for Sankey chart creation. This typically involves:

• Identifying source, destination, and flow variables.
• Categorizing the data to ensure consistency and clarity in the visualization.

Step 3: Selection of Tools

Choose a tool that can effectively create Sankey charts, such as:

• Tableau, which has a user-friendly interface and extensive visualization options.
• R or Python, for more customizable chart creation using libraries like ggplot2 in R or networkx and matplotlib in Python.

Step 4: Design and Layout

Adjust the layout to ensure clarity:

• Scale the widths of the arrows according to the flow quantities.
• Color code different categories for better differentiation and visual impact.
• Hierarchy of the chart to show the flow direction or importance of sources and destinations.

Step 5: Review and Refinement

Iteratively review and adjust the chart for:

• Clarity – Ensure that the chart is easy to understand.
• Consistency – Maintain uniformity in the use of colors and labels.
• Accessibility – Ensure that the chart is accessible to all audience members, including those with color blindness.

Applications of Sankey Charts

Business Intelligence

Sankey charts can provide insights into supply chains, sales pipelines, or customer journeys, helping businesses optimize their processes and identify areas for improvement.

Energy Management

In renewable energy, Sankey charts are invaluable for showing sources of energy (solar, wind, etc.), their transformations (storage, conversion to electricity), and ultimate distribution or use in the grid.

Environmental Modeling

Environmental scientists use Sankey charts to visualize different types of pollution flow, including where pollutants originate from, their movement through various environmental systems, and where they are ultimately deposited.

Social Sciences

These charts are also used to illustrate social processes, such as migration patterns, educational pathways, or career transitions, helping to identify trends and inform policy.

Conclusion

Sankey charts represent a powerful tool for conveying complex relationships and data flows in a visually intuitive manner. Whether it’s in business analysis, environmental studies, or social sciences, the use of Sankey charts can make the presented information more engaging and easier to understand for a broader range of audiences. By following the steps outlined above, anyone can create a compelling and informative Sankey chart that enhances data communication and decision-making processes.

SankeyMaster

SankeyMaster is your go-to tool for creating complex Sankey charts . Easily enter data and create Sankey charts that accurately reveal intricate data relationships.