So you&#x27;re confounding average CPC with search advertising margin. Great. And then making a bunch of statements about the cause for a decrease in CPC with no factual basis. Here&#x27;s another plausible narrative:<p>Mix of traffic is shifting as traffic builds in new platforms (e.g. mobile, emerging markets, YouTube), knocking down average CPC. Then we&#x27;re getting a Simpson&#x27;s paradox (<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Simpson%27s_paradox" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Simpson%27s_paradox</a>) effect causing average CPC to decrease.