So I just got semi-serious about running some AdSense sites over the past 6 months and the eCPM's have hovered between 1.38 and 1.42 [yes it's that close] when I look at the eCPM for each month.  Obviously some deviation day to day but pretty damn close to a buck forty in aggregate.  So far for January I am sitting at 0.80 for an eCPM.  I know it's not a huge sample size but the daily pageviews are fairly consistent [actually a bit higher] than where they were in December.  I am trying to justify this by thinking that somehow a lot of ad buyers buy inventory for the year and have to get setup to do another big buy now that it's a new calendar year but that thought isn't close to comforting.Is this happening to anyone else?EDIT:  I run a lot of websites and the ratios of pageviews are about the same this month to last month but just to be clear the eCPM I posted is for >20 websites in a variety of niches, it doesn't accurately depict any one domain.
Is eCPMs dropping by about 50% in January a usual behavior on Google AdSense?
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