On Monday, Google announced that as of March 29, 2017, the AdWords default view-through conversion window will shrink from 30 days to one day.

View-through conversions are counted when a user converts after a display or video ad impression is viewable but not clicked on.  With this change, only conversions that occur within one day of an add impression will be reported in AdWords as view-through conversions (VTCs).

With this new update, it will applied to new conversion actions, as well as existing ones currently set to the default conversion window.

View-through conversions aren’t going to be included in the Conversions column in AdWords.  This change is only going to affect VTC column reporting.  The last viewable display or video ad impression will get credit for the VTC only if a user has not interacted with an advertiser’s other ads.

By shrinking the default attribution window for view-through conversions to just a single day will probably make sense to a lot of advertisers.  As Ben Wainberg, manager of display marketing at Jet.com, tells Google, “We’ve found ad views are more likely to lead to a purchase within one day, when our message is fresh in customers’ minds.”  Advertisers can still customize the window setting for each conversion action from Conversions under the Tools tab.

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