Starting in late April, 2016, AdWords will begin rolling out a new calculation for impression share, which will potentially affect your reports in the AdWords API if you rely on
impression share columns and run Video Campaigns.
Historically, a small percentage of impressions on YouTube videos were not being included in the calculation of the impression share columns. We've implemented an improved algorithm to more accurately count impression share volume that now accounts for these impressions.
We plan to roll out the improved calculation over the next few months for all accounts and impressions, so if you run campaigns on YouTube, your impression share statistics will become more accurate when your account goes live.
If you have any questions about this change, or other questions about the AdWords API, please contact us via the
forum or the
Ads Developers Plus Page.
- Michael Cloonan, AdWords API Team