How to Create a Rolling Average on Tables and Visualizations

This article describes how to go from a crosstab with a Date/Time variable set...

...to a table or visualization with a lagged rolling (aka smoothing or moving) average:

Requirements

• A table or visualization with a Date/Time variable.

Note: You must apply the rule directly to the input table if you see a table icon in the Data > Data Source > Data field in the Properties of a visualization.

You will also see a warning in the Rules section of Properties if you have applied a rule directly to a non-compatible visualization, and you will need to apply it to the input table instead. For example:

Method

1. Select your table or visualization.
2. Go to Data > Rules in Properties.
3. Select Plus (+) > Cell Content > Replace Value with Rolling Average.
4. Set the Number of periods to roll.
5. OPTIONAL: Tick Dates are in the rows if applicable.
6. Press OK.

Please note the following:

• A lagged rolling average is computed. For example, if January has a score of 3, February 4, and March 6, the 3-period rolling average for March is (3 + 4 + 6) / 3 = 4.33333333.
• Where values cannot be computed due to insufficient data, the value is shown as NaN. For example, if January has a score of 3, February 4, and March 6, the 3-period rolling average for the three months, respectively, are NaN, NaN, and 4.33333333.
• This rule is only applied to the first statistic selected in each of Statistics > Cells and whichever is appropriate of Statistics > Below and Statistics > Right.
• You may not have a NET in the variable containing the dates.
• The statistical testing results in the table are not changed by this rule. That is, they reflect the results for the original, unrolled statistics.

Next

How to Use Rules in Displayr