Basic Unique Visitor question

[fern1]

At the company, we are connecting PowerBi with Adobe. Our numbers (Adobe vs BPI) were different for the same metrics and time period. However, we realized that if we added up manually each day of the month for unique visitors (just an example), the total was different than what Adobe is showing as the total. Is there an explanation for this? Am I missing something elemental about it?

Here we are getting total unique visitors as 50 but adding all the rows the real total is 82.
What am I missing here?

[Pablo_Childe · Accepted solution]

Hi so unique visitors one has to be careful as depending on time periods reported on one will get some deduplication

In this case you have 2 time frames.

UVs by day

UVs by month.

In this case the sum of daily will be greater than the Monthly total as some daily visitors are deduped when looking at Monthly time frame.

day 1 UV a. UV b = 2 daily UVs

day 13 UV a. UV c = 2 daily UVs

May UVs

a+ b+ c =3 UVs(a is deduplicated from monthly total as unique count),

When try to quantify UVs daily like this or if monthly totals in a year thens its better to do daily avg./monthly Avg.

GLTU

[Jennifer_Dungan]

Well said.. I am just going to append a "scenario" this to help with the mental visuallization.

I am a user. I come to the site, on May 1st, 4th and 17th for instance...

When you have Daily granularity as shown in the screenshot. I would be counted as a UV on the three rows that correspond to the days I came to the site. 

But at the "total" row, that is based on the report period (the month of May). I am only one user... I shouldn't be counted three times because I came to the site three times... within the month, I am still only a single user, and therefore the "total" will be less than the sum of the column.

The Total de-duplicates metrics like Unique Visitors. When you are exporting to external data systems, this must be taken into account.