How is Visitor Groups "Number of Visits" tracked?


We are looking into the use of Visitor Groups, and have created a Visitor Group for new visitors. We added the criteria that Number of Visits had to be less than 1 since January 1, 2017.

However, in the Visitor Group statistics we see only a handful of visitors every day in this group, which does not match with reality.

- How does Episerver keep track if a users is a returning visitor? 

- Is IP address being logged, and in that case, is it possible that Episerver is tracking the IP address of our load balancer?

Anyway, what other reasons could there be for this not working correctly? It seems pretty straight forward, and I don't see what we might be missing?

I apreciate any input or suggestions :)

Edited, Feb 06, 2018 16:38
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