Sankey charts, named after engineer and physicist Francis H. Sankey, have been used to represent flow data with style for over 150 years. These unique charts allow for the visualization of how energy, material, or resources move between different points, highlighting the magnitude of transfers and revealing patterns and trends that are not immediately obvious in raw data.
What are Sankey Charts?
Sankey charts feature nodes placed along a primary axis, with “flows” or arrows connecting these nodes, indicating the direction of movement between them. The width or thickness of the arrows visually represents the magnitude of the flow at that particular connection, thus giving a sense of “heaviness” to larger transfers.
Benefits of Using Sankey Charts
- Clear Visualization: They effectively communicate the flow of energy, material, or resources with a visually appealing and straightforward display.
- Facilitating Comparison: Users can easily compare the magnitude of flows between different sources and destinations.
- Highlighting Patterns: Sankey charts can reveal complex patterns and trends over time, making it easier to identify key contributors and beneficiaries of the flows.
- Improving Data Understanding: For decision-makers, the ability to visualize and understand resource movements is crucial for optimizing processes and making informed decisions.
Creating a Sankey Chart
Tools and Software
Many popular data visualization tools such as Tableau, PowerBI, D3.js, and Python libraries like Matplotlib and Plotly offer built-in features or libraries for creating Sankey diagrams.
Steps to Create a Sankey Chart
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Data Preparation: Gather your data, which should include a list of source nodes, destination nodes, labels (optional), and the volume or quantity of the flow. Optionally, include time or category data.
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Choosing Axes: Designate an axis to represent sources and another for destinations. The connecting arrows will then represent the flow from one node to another.
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Setting Widths: The width of each arrow should be proportional to the flow volume or quantity for clarity.
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Styling: Customize your chart’s appearance with colors, labels, and tooltips to enhance readability and make the flow story more engaging.
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Review and Refine: Ensure the chart is clear and easily understandable. Iterate on design and data until the Sankey chart effectively communicates the intended message.
Applications of Sankey Charts
1. Energy Sector: Sankey charts are commonly used in the energy sector to represent the transfer of energy between various sources, such as power plants, electricity grids, and end-users. This allows stakeholders to understand consumption patterns, identify energy waste, and optimize production capacity.
2. Supply Chain Analysis: In logistics and manufacturing, Sankey charts illustrate the movement of goods or materials from suppliers to manufacturers to retailers and consumers. They help in identifying bottlenecks, inefficiencies, and opportunities for optimization.
3. Environmental Management: Environmental planners can use Sankey diagrams to track the circulation of pollutants and natural resources within ecosystems. This aid in designing effective policies and interventions for conservation and sustainability.
4. Healthcare: In healthcare, Sankey charts can depict the flow of patients between different stages of care or systems, helping medical administrators and policy makers to identify areas requiring attention, such as high patient turnover or underutilized resources.
5. Economics: Economists frequently utilize Sankey charts to visualize economic flows, from trade between countries to the distribution of sectoral contributions to a country’s GDP.
Conclusion
Sankey charts provide an engaging and intuitive way to understand complex flows of energy, material, or resources. Their ability to visually represent trends, patterns, and magnitudes makes them an indispensable tool for data analysts, researchers, and decision-makers in various fields. By leveraging these charts, professionals can gain valuable insights, inform strategic decisions, and communicate findings more effectively to stakeholders.
As technology advances, so do the capabilities of tools for creating Sankey charts. With the availability of sophisticated software, building these charts has become more accessible and user-friendly, allowing organizations to harness the full power of Sankey charts for their data visualization and analysis needs.
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.
