We recently announced several changes and improvements to the way we report AdWords impression share (IS). We are now making these changes available through the v201209 version of AdWords API reports as well.

Around the second week of December, the following new columns will be available for account, campaign and adgroup performance reports:

• ContentImpressionShare
• ContentBudgetLostImpressionShare
• ContentRankLostImpressionShare
• SearchBudgetLostImpressionShare
• SearchExactMatchImpressionShare
• SearchImpressionShare
• SearchRankLostImpressionShare

We now provide distinct search and display columns, so you can clearly separate search and display impression share. We also support “Hour of day” segmentation to evaluate how your ad coverage varies by the hour. You can get hourly segmentation of impression share data by requesting the HourOfDay column in your reports.

Finally, we’re improving the accuracy of how we calculate impression share data. As previously mentioned on our product blog and via social media, historical IS reporting data is now only available going back to October 1, 2012.

Phasing out old IS columns in February 2013

With the new IS columns now available, we’re planning to phase out the old IS columns (BudgetLostImpressionShare, ExactMatchImpressionShare, ImpressionShare and QualityLostImpressionShare) in February 2013.

If you face any issues with the above changes or have any questions about the AdWords API, you can ask us on our developer forum, or at the upcoming live office hours with the Developer Relations team.

 - Anash P. Oommen, AdWords API Team

We recently announced upcoming changes to AdWords Impression Share metrics. If you are using the AdWords API to download BudgetLostImpressionShare, ImpressionShare, QualityLostImpressionShare and ExactMatchImpressionShare metrics in account and campaign performance reports, then the upcoming change will affect you in the following ways:

• We will revise campaign-level Impression Share metrics from May 1, 2011 to present. You may notice some adjustments in past campaign-level Impression Share data once this change goes live.
• We will remove campaign-level Impression Share metrics prior to May 1, 2011. If you depend on historic impression share data prior to May 1, 2011, then you need to download them before January 30th.
• All Impression Share metrics will only be updated once every day, by afternoon PST. In addition, the data will no longer be available for segmentation by hour. If you have a saved report definition that requests hourly aggregation of IS data, then those definitions will stop working once the new changes go live.

If you wish to backup old Impression Share data or make changes to the way you use Impression Share to control your AdWords campaigns, please do so before January 30th. If you have any questions about the AdWords API, check out our developer forum.

 - Anash P. Oommen, AdWords API Team.