Are Your Ads Appearing Everywhere They Can? Google’s Impression Share Report
A cool report that is buried deep in Google AdWords Reports Tab is called the “Impression Share” Report, sometimes called the IS report (which looks like the word “is” to the rest of us 
).
This report gives you valuable stats on the “reach” of your ads, meaning how much of the available places your ad can show does it appear.
To access this report:
- Go to the Google AdWords Report Center, and click on Create New Report.
- Click on “Campaign Report”
- Go to Section 3 - Advanced Settings (Optional)
- Add or Remove Columns - Check off the following boxes:
- Impression Share (IS)
- Lost IS (Rank)
- Lost IS (Budget)
- Exact Match IS
- Create the New Report
This report shows you out of the total available impressions for your keywords is your ads showing. The Lost IS columns reflect what percentage of impressions your ads aren’t showing for, either because of a poor quality score & low CPC (Rank), or because the campaign exceeded its budget (Budget).
This is a valuable metric, which can be used to gauge the health of your campaigns’ quality score. Also, you can see if your budget is set too low, and therefore your ads aren’t appearing for all the available searches.
BTW, I heard from Brad Geddes that impression share never reaches 100%, although he has seen 97-99%. He doesn’t know the reason for this, so if you are getting in the high 90s, that means you are doing well. :)