When should you use a line chart for your data analytics?

2 Limitations of line charts

Line charts are not without their drawbacks, and it's important to be aware of these limitations. If the data points are not evenly spaced along the horizontal axis or the vertical axis does not start at zero, the chart can give a false impression of the slope or proportion of the data. Too many data series on one chart, or data series with different scales or units, can make it difficult to compare or distinguish them, as well as read the labels and legends. Additionally, if the data does not have a logical or meaningful order along the horizontal axis or a continuous or linear relationship, then a line chart may be inappropriate or irrelevant.

3 Best practices for line charts

To avoid the pitfalls and maximize the potential of line charts, you should follow some best practices when creating and interpreting them. Select a line chart only if your data has a clear and consistent order along the horizontal axis, as well as a smooth and continuous relationship along the vertical axis. Utilize a line chart to show changes and trends in your data over time or across categories, not to show absolute values or proportions. When comparing multiple data series on the same chart, limit it to four or five data series to avoid clutter and confusion. Make sure the horizontal axis is evenly spaced and the vertical axis starts at zero, or use a logarithmic scale if appropriate. Additionally, be mindful of not using a line chart to show the slope or angle of the data, as these can be misleading or irrelevant.

4 Examples of line chart applications

Line charts can be used for a variety of data analytics applications, such as business, finance, science, health, and education. For instance, in business you can use a line chart to show the sales, revenue, or market share of your company or product over time or across regions. Similarly, in finance you can use a line chart to show the price or performance of your stocks, bonds, or funds. In science you can use a line chart to show the temperature or speed of your experiment or observation. Additionally, in health you can use a line chart to show the weight or blood pressure of your patient or population. Lastly, in education you can use a line chart to show the score or progress of your student or class. All these applications allow you to compare with your competitors, portfolio, index, hypothesis, model, target, average, goal, and standard.