I haven't received this email yet, but apparently other AdSense publishers have:
We're writing to inform you of an upcoming change to the AdSense for content smart pricing system. As you may know, smart pricing is the system Google uses to ensure that advertisers are able to maintain a consistent return across sites in the Google Content Network. It's designed to encourage advertisers to opt-in to the content network while remaining confident about their ROI.
We're continually working to refine and improve our smart pricing system. In the next few weeks we'll be rolling out a few changes, and we've identified that these changes may have a noticeable negative impact on your revenue. These changes are enhancements to the smart pricing calculation that will more accurately reflect advertiser willingness to pay for traffic from specific web properties and will return more consistent advertiser value across our content network.
As advertisers notice consistent value and improved ROI on the content network, they'll spend more on AdSense sites. We're confident that these modifications will help generate long-term value for advertisers and improved revenue in the long run for publishers.
You can also read more about smart pricing in these resources:
Thank you for your understanding.
The Google AdSense Team
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