Add a period over period comparison
This walkthrough shows you how to add a period over period (or date offset) comparison.
Period over period lets you compare measure values for one period of time against the results from a previous or subsequent period of time, for example year-over-year.
Related video: Period over Period Analysis
A period over period measure can be added to any metric set with a measure and a time dimension hierarchy.
This example starts with a new metric set.
2.1. Create a metric set
From the main menu, click New and click Metric Set. (The steps are similar when editing a metric set on a dashboard or another view instead.)
Add a measure and a time dimension hierarchy. In our example, we dragged the Month level of a time dimension hierarchy found under a date/time column, and dragged it to Rows (Data Points). We also chose to re-visualize to a bar chart.
The time dimension hierarchy can also be selected on Slicers or Columns if you prefer.
2.2. Filter the dates
A period over period measure is most useful when comparing against a filtered range of dates.
In our example, we will filter our time dimension to show a single year, which you can do from the filter icon in the Data Analysis Panel.
2.3. Add a period over period measure
In the toolbar, click Add Period Over Period. (When editing a dashboard or another view, you can find this option under Data Tools in the toolbar.)
The Period Over Period Comparison dialog is displayed.
By default, the previous year's data is selected for comparison. Adjust these options if you prefer.
When editing a dashboard, there is a checkbox labeled Automatically Add Parameter Control. This will add a Time Lag filter allowing you to change these period over period settings while viewing. You can also add this filter later.
Click the submit button at the bottom of the dialog to update the metric set with a new measure displaying data from a different time period directly alongside the original.
To rename the new measure, click to edit it in the Data Analysis Panel and change the Caption.
3. Returning all comparison data
A period over period measure normally only returns values for dates where there are corresponding values for the input measure (for example, OrderQty). However, there may be situations where you want to see all of the period over period measure values, regardless of whether there is anything to compare against. For example, you may want to see the period over period values extended into the future in order to determine sales goals.
As an example, consider the same bar chart visualization of OrderQty and OrderQty PoP-1Year measures, but without the member filter applied.
To have this chart show all of the period over period values, open the Data Analysis Panel and edit the OrderQty PoP-1Year measure.
In the Configure Metric Set Element dialog, select the Return All Parallel Period Comparison Data checkbox and click Submit.
The chart now displays all of the period over period values, which includes dates where there are no OrderQty values.