Have you ever run a test on one of your ad units, and wished you could more easily compare performance from before and after the test? If you've created and saved an ad unit in your account, you'll now find an easy way to do this in your ad units report.
Start by visiting the Performance Reports tab and choosing the ad units report (you'll find it in the navigation bar under "Entire account by day").
Search for the name of an ad unit you've updated and select it.
Open the date range box and set a window of dates before your test -- for example, two weeks.
Check the box marked "compare to other dates" and include a similar window of dates after you made the change to your ad unit.
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