I have a website which has some pretty massive spikes in visitor numbers due to its subject. (only natural search engine traffic, no spam) The spikes are mostly very short in time, sometimes as short as an hour.
I recently had such a spike and now in the following days with normal visitor numbers my eCPM is terrible. It is so low I am even considering dropping Adsense and to make my own ads for affiliate programs.
Do other webmasters with Adsense and spikes in visitor numbers have this same experience of very low eCPM when visitor numbers are back to normal? Trying to determine if it is coincidence or a pattern.
My EPC has been dropping every day since hitting recent highs just after the Google changes to AdWords earlier this month. Now the EPC is the lowest I've seen it in several months. I think it is because advertisers are adjusting their campaigns to the new AdWords model.
I know I've dropped some of my AdWords campaigns and lowered some PPC amounts because of poor performance since the change. Maybe it's just August but we'll see.