Earlier this week, Google announced via the AdWords blog, that impression share metrics will soon be available to advertisers at an ad group level. (Previously, impression share was a metric that could only be viewed at a campaign level.) The impression share level metrics available will be overall impression share (percentage of time ads in a group appeared vs. the estimated impressions they were eligible for), exact match impression share (percentage of time that ads appear on exact queries being place compared to eligible universe for appearance), and Lost Impression Share Rank (share of impressions lost due to AdRank which is a metric calculated using max bid and quality score).
There are multiple ways in which the more granular view of impression share will be useful towards overall campaign analysis and optimization. Here are just a couple of ideas of how to start looking at the new data view:
It’s also important to note that in addition to the new metrics that will be reported for ad groups, Google indicated that they would be adjusting the algorithms to be able to provide a more accurate impression share number. As a result, impression share will only be calculated once per day, and campaign level impression share stats will be adjusted to reflect the more accurate data as far back as May 2011. Advertisers who want to save campaign level impression share metrics prior to May of last year are being encouraged to download reports before January 30th.
View the original Google AdWords Blog announcement at: https://adwords.googleblog.com/2012/01/coming-soon-ad-group-impression-share.html