This is the second part of a two-part series on Tableau Playbook - Line Chart. In the first part, we delved into the concept and basic process of the line chart. Check it out in case you missed it.
In this guide (Part 2), we will focus on the advanced usages of the area chart. By analyzing a real-life dataset, Rossmann Store Sales, we will practice three of the typical line charts with advanced features step by step. Meanwhile, we will draw some conclusions from Tableau visualization.
If we want to illustrate the seasonal trends by years, we can consider a discrete line chart.
This discrete line chart gives us a clearer idea of the monthly trends by years. We can see in every year, the sales increase rapidly since September, and peaked in December.
In order to show the overall trend, we can change the previous chart into a continuous line chart.
mmm yyyy. For more date format information, please refer to the supported date format symbols table.
Compared with the previous discrete line chart, we realize this continuous line chart connects the separate parts into a single line. It gives a more macro and complete time series analysis. From this overall trend, we can see the sales obey the yearly seasonal pattern.
In the last section, let me introduce two common techniques often used in line charts: trend lines and forecast.
For lines (continuous), try 1 date, 0 or more Dimensions, 1 or more Measures.
Hold down the Control key (Command key on Mac) while clicking to multiple select "Assortment", "Date" and "Sales", then choose "line (continuous)" in Show Me. Tableau will generate a raw continuous line chart automatically.
Aided by the trend lines, this line chart shows that sales are steadily growing despite seasonal fluctuations, rather than emphasizing monthly spikes. We can see the sales of extra type has the highest growth rate.
With the help of the forecast, we can predict future sales roughly based on historical data. The shaded bands show the 95% prediction intervals, which means Tableau is 95% confident that the correct prediction exists within this range.
In this guide, we have learned the advanced usages of the line chart. First, we built the two typical line charts: discrete and continuous line chart. Moreover, We enhance the line chart with trend lines and forecast.
You can download this example workbook Line Chart and Variations from Tableau Public.
In conclusion, I have drawn a mind map to help you organize and review the knowledge in this guide.
I hope you enjoyed it. If you have any questions, you're welcome to contact me at [email protected].
If you want to dive deeper into the topic or learn more comprehensively, there are many professional Tableau Training Classes on Pluralsight, such as Tableau Desktop Playbook: Building Common Chart Types.
I made a complete list of my common Tableau charts serial guides, in case you are interested:
|Categories||Guides and Links|
|Bar Chart||Bar Chart, Stacked Bar Chart, Side-by-side Bar Chart, Histogram, Diverging Bar Chart|
|Text Table||Text Table, Highlight Table, Heat Map, Dot Plot|
|Line Chart||Line Chart, Dual Axis Line Chart, Area Chart, Sparklines, Step Lines and Jump Lines|
|Standard Chart||Pie Chart|
|Derived Chart||Funnel Chart, Waffle Chart|
|Composite Chart||Lollipop Chart, Dumbbell Chart, Pareto Chart, Donut Chart|