This is the third and final part in the Tableau parameters series.
While Tableau has a built in Moving Averages calculation, it is preset to only the previous 2 periods. But what if the user wants to look at the moving averages over a longer period of time? Dynamic Moving Averages are a great way to give the end user control over how many previous periods they wish to use for the moving average calculation.
Let’s get started.
Firstly, we will building a standard moving averages chart on a dual axis with a standard sales over time chart using sample superstore data.
Creating the Dual Axis Chart
- Drag sales on to the rows shelf, and order date on to the columns shelf. Change Order date to a continuous month.
- Hold control and click and drag your sales pill currently on rows to rows again.
- Right click on the sales pill on the rows shelf and change it to moving average.
- Right click on the same sales pill on the rows shelf select Dual Axis.
Creating and using a Parameter
Next, create a Parameter to select the number of months to use for the moving average calculations.
Give it a meaningful name (Number of Months for Moving Average).
Change the range to your minimum and maximum month range (the example below uses 2 months as a minimum and 30 months as a maximum range).
Thirdly, double click on the moving average sales pill.
Where it shows -2, replace the 2 (keep the negative) with the new parameter.
Synchronize the Axis
Finally, synchronize the sales axis by right clicking and selecting ‘Synchronize Axis’.
Your dynamic moving average chart dual axis with a sales over time chart is now complete.
If you are ready, give this challenge a go:
2021 Week 33 | Tableau: Can you create a moving average chart with a focus on selected subcategories? – Workout Wednesday (workout-wednesday.com)
