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The graph shows how many users have been exposed to 1, 2, 3 ore more impressions. By passing the pointer on each column you can see the user% for each impression count.
Unique Users
The tab on the right side of the screen shows data about Unique Users, therefore the number of users that have been exsposed the first time to the unit.
the other tabs below the Unique user" one shows the total impressions count and the the Avarage frequencency per user, therfore how many times (in average) a user has peen exsposed to the uint.
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