I see fluctuations in my estimated revenue
You might see fluctuations in revenue reflected in your reports due to the lag between gross click counts and invalid click detection. Revenue is reflected quickly and then adjusted downward for any invalid clicks, which take longer to process. After clicks occur, estimated revenue are increased based on these recorded clicks. However, processing for invalid clicks is completed after this initial estimate, and the corresponding revenue might then be revised downward in your reports. This behavior is noticeable mostly for accounts with low traffic volume or a high proportion of invalid clicks. Please be assured that after these initial fluctuations, revenue eventually stabilizes, and earnings are computed in the same manner as they were prior to this change.
Invalid click activity consists of any clicks or impressions that may artificially inflate an advertiser's costs or a publisher's revenue, and for which we decide not to charge the advertiser. This includes, but is not limited to, clicks or impressions generated by a publisher clicking on his own ads, a publisher encouraging clicks on his ads, automated clicking tools or traffic sources, robots, or other deceptive software.