The Sankey chart is a visual tool that represents the flow of a quantity – most commonly used for showing energy consumption, material flow, and data transfer. These charts are named after Captain Matthew Henry Phineas Riall Sankey, who invented them in 1898 to depict the energy efficiency of the steam engines he analyzed. Since then, Sankey charts have become incredibly versatile, with applications in fields ranging from biology and economics to physics and IT.

In its essence, a Sankey chart visualizes processes where materials or data flow starts at one point and moves to multiple outputs. The width of the arrows is proportional to the volume or significance of the flow. This makes understanding complex flows and allocations of resources an almost effortless process.

Creation of Sankey Charts

Creating a Sankey chart requires several steps, varying depending on the software you are using, from basic spreadsheet programs like Microsoft Excel or Google Sheets to more specialized data visualization tools such as Tableau, PowerBI, or tools dedicated to Sankey charts like SankeyFlow, which are specifically designed to cater to unique requirements for data flow representation.

Step 1: Data Preparation

First, prepare your dataset with three essential columns: source (origin of the flow), target (destination of the flow), and value (amount or weight of the flow). Additional columns can help in varying the color, labels, and other visual properties.

Step 2: Choosing the Right Tool

Select the software that best fits your needs and skill level. Spreadsheet tools are excellent choices for simple Sankey charts, especially if you need to update or manipulate data frequently. For more complex and customizable charts, dedicated software or data visualization platforms offer a wider array of options.

Step 3: Designing the Layout

Design your layout by arranging categories or nodes on the chart. Typically, nodes are arranged along a vertical or horizontal line, and the source is placed below or to the left, with arrows pointing towards the targets.

Step 4: Adjusting Appearance

Customize the appearance to enhance readability and appeal. This includes adjusting colors, label placement, and the width of flow paths based on the data’s magnitude.

Step 5: Final Checks and Presentation

Review the chart for consistency, clarity, and accuracy. Ensure that the chart reflects all data correctly and is easy to interpret. Finally, prepare your chart for presentation or publication, ensuring it is easily accessible and visually pleasing.

Applications of Sankey Charts

Sankey charts are incredibly versatile across various industries:

• Economics: Economists use Sankey diagrams to illustrate the flows of money, goods, and services between sectors of the economy.
• Biology: In biological studies, Sankey charts are used to trace the interactions between different components of ecosystems or metabolic pathways, showing how energy and nutrients are transferred.
• Engineering: In mechanical and environmental engineering, Sankey charts can represent the flow of material or energy through systems, helping in optimizing energy efficiency or managing waste flows.
• Information Technology: IT professionals use Sankey charts to visualize data traffic, showing how data moves between different nodes or systems in a network.
• Environmental Science: For environmental studies, Sankey charts can illustrate the complex flows of pollutants, resources, or climate-related data across different regions or systems.

Conclusion

Sankey charts are a powerful tool in the arsenal of data visualization techniques. Their ability to clearly and effectively communicate the flow of quantities makes them indispensable for researchers, engineers, and decision-makers in various fields. By choosing the right software and following a structured approach to chart creation, users can unleash the full potential of Sankey diagrams, significantly enhancing the clarity and impact of their data presentations.

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.