Why do the geography report impressions and the impressions under the Performance by Campaign don't match up?

We are filtering out results coming from the DSP that do not have either a country, region or city. There isn't a way to place them on the map without all the information available.

Why am I seeing a dash mark in the geo report?

The reason you're seeing the dash mark in the geo report is that this means that the DSP didn't send us the reporting information that's associated with that zipcode.  Please note that this is still valid data.

What does ‘Other’ mean in the geo category section of the reports?

The 'Other' category row in our reporting dashboard is in there because in the event that there are too many geographic rows returned for that geo component, we collapse all the additional rows into one single component. We only show reporting on the top 1,000 locations by impressions.