Unique Visitors with Event X higher than pure Event X count

[FraCalzo]

Hi everybody,

I found the following strange behavior. I have the event213 that, in February 2020, counts up to 1,228.

Then I made a segment (at a Visitor level) keeping only those visitors who fired event213 at least once. If I check Unique Visitors metric over that segment, i find a number higher than the pure count of event213. How can it be possibile?

Below, a screenshot of February 2020 data:

where "[AC] Utilizzo del Calendario" is event213 and "Clienti Utilizzatori del Calendario" is the name of the segment. The segment is simply built as it follows:

This is not logical to me.

Could someone explain me this phenomenon? Is it an error?

I appreciate any help on this.

Thanks in advance,

Francesco

[Andrey_Osadchuk · Accepted solution]

Hi Francesco,

That really looks odd. My hypothesis is that the [AC] metric could be decreased by offline data ingestion with negative numbers.