Location targeting: Radius vs. zipcodes within same radius
It may sound weird, but:
1. Pure Google Search, radius-style targeting within 15 miles radius.
2. Pure Google Search, zipcodes-style targeting, all zipcodes are within same 15 miles radius.
Impressions 1 > Impressions 2 almost by 50%.
Re: Location targeting: Radius vs. zipcodes within same radius
What is the difference in population estimates when you compare the 15 mile radius to all the combined zip codes (zip codes often won't fit within a radius and can extend erratically for many miles outside the radius, and hence can have a greater population).