Customizing Calendar and the Effects on Historical Data

[occ2]

My organization is looking into the option of redefining the start of the week dimension from Sunday to Monday and we are trying to understand the impact on historical data. In the attached article, we read "When a calendar’s definition of weeks and months changes, historical data is not altered." Can anyone explain what this means? If we use the week dimension and are analyzing a date range prior to this change, would those dimensions still show as week beginning on Sunday? Or would it redefine past weeks as week starting on Monday?

Thank you!

https://experienceleague.adobe.com/docs/analytics/admin/admin-tools/manage-report-suites/edit-report...

[Jennifer_Dungan · Accepted solution]

I believe there are some calculations based on date configurations during data processing... Anything that is calculated should be fine, but it can be hard to determine which is which.

I've not actually changed the date settings, instead, for the users that needed Monday to Sunday reports, I used a series of custom date ranges.

However, if I were to do that, my first step would be to use an existing, or create a new QA/Dev/UAT suite and get some base data collected over a few months (preferably)... then change the date configuration on the test suite. in fact, I may be more tempted by a new suite, and track the existing QA/Dev suite in parallel (i.e.  have the same data in 2 suites)

Then I could change the date configuration, and with 2 identical data sets, I could compare how reports will look. Basically, try to do due diligence prior to making the change so that you know what you are in for....

Good Luck

[occ2]

Thanks for this advice, Jennifer. If we proceed with this methodology for testing I will provide an update with the results. 

[yuhuisg]

I haven't changed any report suite's calendar before. But I'd say it works like the following:

Let's say you have the following data:

• Sunday 3 Sep 2023: 10 page views
• Monday 4 Sep 2023: 14 page views
• Tuesday 5 Sep 2023: 15 page views
• Wednesday 6 Sep 2023: 18 page views
• Thursday 7 Sep 2023: 17 page views
• Friday 8 Sep 2023: 16 page views
• Saturday 9 Sep 2023: 20 page views
• Sunday 10 Sep 2023: 19 page views
• Monday 11 Sep 2023: 13 page views

And let's say your original calendar setting was with a standard Sun-Sat week.

Then when you reported page views by week, AA would report the following:

• Week 36 (Sun 3 Sep - Sat 9 Sep): 10 + 14 + 15 + 18 + 17 + 16 + 20 = 110 page views
• Week 37 (Sun 10 Sep - Sat 16 Sep): 19 + 13 = 32 page views

Now, if you were to change the calendar to a Mon-Sun week, then:

• There are no changes to the underlying data. That means, all of the above daily page views remain exactly the same.
• AA calculates the week's data when you generate a report / dashboard based on your updated setting.

And AA should report the following:

• Week 36 (Mon 4 Sep - Sun 10 Sep):  14 + 15 + 18 + 17 + 16 + 20 + 19 = 119 page views
• Week 37 (Mon 11 Sep - Sun 17 Sep): 13 page views

[Jennifer_Dungan]

This is how I would expect it to work... I think there are some old legacy fields that are actually set during processing (mobiledayofweek - part of the mobile dimensions; and weekly_visitor which is part of the old Weekly Unique Visitors metric... ), but you likely aren't using these...  That data also wouldn't be updates with the change, but new data going forward would be recorded based on your calendar configuration.

In most cases, you will use the standard Day of the Week and just Unique Visitors broken down by week (rather than the specific "Weekly Unique Visitors metric)