The number of page views for individual posts and total page views have dropped precipitously. It appears that Google is under reporting these page views, which of course results in less earnings for our website.This blog owner does not understand the effect of referer spam upon Stats - nor the separation of AdSense and Stats.
Some blog owners think that they know what pageview counts are appropriate, for their blog - and are unhappy when Stats does not display counts that agree with their expectations.
Not all blog owners understand that Stats displays pageview counts in their own context.
Every different visitor counter produces different statistics.
There are not any two visitor counters that will ever show the same figures - and Stats, by its unique way of identifying visitor activity, will differ even more from any third party visitor counter. Also, referer spam, and retroactive corrections, will cause Stats counts to fluctuate significantly, with some blogs.
Some referer spam may even be crafted to target specific blogs. Blogs which publish complete posts on the main page will receive a maximum amount of main page traffic with a minimum amount of individual posts traffic.
Referer spam, targeting the right blog, can have good results from slight effort.
An imaginative referer spam publisher can attack such a blog, using a minimum amount of bogus individual post page activity, and still be noticed by the blog owner - and have a good chance of receiving investigative clicks ("What is this link in the log?") - because most organic traffic will reference the main page.
Given a minimum amount of traffic involved in such a spam attack, Google could take months or years to detect the attack. The blog owner will become used to seeing the bogus counts, and may equate the referer spam to normal visitor activity.
Subtle spam attacks, when removed by Google, will produce maximum visibility.
When Google does detect the spam attack, they will remove all similar visitor activity, retroactively. The blog owner may see pageview counts for previous months and years drop precipitously.
Blogs with minimal organic visitor activity - such as blogs with large main pages, containing few posts - will be especially susceptible to this confusion. Seeing pageview counts drop rapidly, some owners will not take the change well.
Stats does not lie. Owners must accept the truth.
Unfortunately, Stats displays do not lie. If Google removes referer spam pageview counts retroactively, blog owners who have been seeing referer spam, and confusing it with genuine visitor activity, will have to accept the truth.