I mentioned a bit ago that Google AdSense had been performing really poorly. I’ve been looking through the recently upgraded dashboard, and it looks like I’ve found some of the reasons why.
Unmatched Ad Requests and Coverage.
Unmatched ad requests are requests for Google to serve an ad where they fail to provide a relevant one. Which explains all the irrelevant rubbish.
Coverage is the percentage of relevant ads out of all the ads provided. Recently, it’s been pretty poor. The most likely cause of this is the pages where the ads have been requested from not having been crawled. I need to see if this can be improved.
I’m not sure if this the only reason why so many irrelevant ads are currently being displayed, but this does need fixing. Part of the problem could be related to recent poor server performance.