|Why Don't My Page Views and Impressions Tally Up?|
You might think your "Page Views" and Adsense "Impressions" would be the same number, but that is never the case. In fact, you can consider yourself having good ad placements if your "impressions" is over 50% of your page views? But what is happening if you have told Google to show your ads 100% of the time? To answer this we must first understand what an Adsense "impression" really is...
How Are Adsense Impressions Calculated?
According to Adsense support, an "impression" is the following "An impression is counted for each ad request where at least one ad has begun to download to the user’s device. It's the number of ad units (for content ads) or search queries (for search ads) that loaded ads." But the bit you really need to understand is the part of the support page that says this "The AdSense 'Impressions' metric uses the downloaded definition for all impressions. Note that the complementary ActiveView viewable metric is used to determine if users actually viewed the impressions." Basically, even if the ad has downloaded it doesn't count if it has not been viewed, like from a search robot or some other program visiting your site, hence the reason the Page Views and Impressions don't tally up because it doesn't count if they have not been seen fully. If an ad has failed to download or if the user closed the tab before it arrived it won't be counted as an impression.
Are Adsense Impressions Important?
While it should be a valuable metric that you can try and grow for an improved Adsense revenue it's sadly tough for Adsense to calculate your true "Impressions" that real people have seen, not robots and programs. What I say is as long as it is at least 50% of your page views you can count yourself as doing OK. One day it might be easier for Adsense to tell a real impression from a failed/fake one, but for now, they are doing the best they can to make sure it's as accurate as possible.