Content:The line chart is an easy-to-understand visualization best suitable to display how the value of an element changes over time (trend). The dimension is plotted on the x-axis and serves as a timeline, while the metric is plotted on the y-axis and indicates values.
To better understand how a line chart works, we can think of the lines within the graph as histories to tell. So the first thing to do is measure the value of an element we want to monitor at different moments in time.
Once we have collected a significant amount of measurements, we place those points within the graph and draw a line to connect them. Again, the goal is to simplify how those values rise, fall, or stay the same over a period of time.
When to use a line chart? Every time you need to visualize movements and trends over time; or show forecasts, it’s the time of a line chart.
Data to use on a line chart
Generally, a line chart has continuous data plotted on both the x and y-axis. As said above, the y-axis displays the value of the variable we are measuring; the x-axis indicates when we measured it.
While some line charts don’t use continuous data on the x-axis as slope charts, we can’t plot data with any significant relationship among the categories shown on the x-axis.
When is the line chart not the best choice?
A line chart is not the primary option for showing quantities of goods, analyzing categorical data, or making part-to-whole comparisons. Moreover, using a large number of metrics will make the chart confusing and challenging to understand. Because of this, remember not to exceed the number of lines because it is generally hard for people to keep track of more than four or five lines.
If you need to display more than five lines, it’s advisable to use color, labeling, and line weight to let the audience pay attention only to the chart’s most essential elements.
How to create a line chart on BStreams
- Add a new project
- Drag the line chart and drop it on the canvas
- Select the sample dataset
- Choose one dimension and n. of metrics
- Click apply to show the result
Example
The following example shows how Microsoft (MSFT) and Apple (AAPL) closed from 2015 to 2019. As the fluctuation of both lines is evident, in the chart below, the BStreams allow you to highlight the main important climbs and develop or increase the thickness of one of the lines that are more important.Highlighting feature
When creating data visualization, charts are an effective way to present data trends, and sometimes, you might wish to highlight specific data to focus the user’s interest on specific events. The way BStreams highlights data is very effective and can be found under the Style – Layout section of the properties bar.
The Highlights message could show only the X value selected, a text or highly customizable using HTML code.
Using HTML code could be helpful if you want special text formatting or to make the highlight referencing a web link.
Increase the thickness option makes the entire line bold.
It’s possible to add an unlimited number of Highlights in a chart, but remember to focus on the readability of the visualization.
Common caveat
The line chart is at the center of numerous debates.
One of the most common debates around line charts is whether the y-axis must start at zero.
Generally, it is not necessary to let the line plot start at zero. However, it is still advisable because it is less confusing for an audience when the y-axis begins at zero since it is the average expectation. However, we must admit that there are still some cases when the zero baselines are not the primary option to choose:
For example, when the range of measurements is small, the distance from the minimum value of those measurements to zero is significant.
Want to learn more about scatterplots? Email us at support@bstreams.io
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